News from Industry

SDP: Your Fears Are Unleashed (Iñaki Baz Castillo)

webrtchacks - Wed, 09/20/2017 - 12:55

We have have had many posts on Session Description Protocol (SDP) here at werbrtcHacks. Why? Because it is often the most confusing yet critical aspects of WebRTC. It has also been among the most controversial. Earlier in WebRTC debates over SDP lead the to the development of the parallel ORTC standard which is now largely merging back into the […]

The post SDP: Your Fears Are Unleashed (Iñaki Baz Castillo) appeared first on webrtcHacks.

Grokking Media in WebRTC (a free webinar for my WebRTC Course)

bloggeek - Mon, 09/18/2017 - 12:00

Media in WebRTC.

What makes it so challenging?

I guess it can be attributed to the many disciplines and different areas of knowledge that you are expected to grok.

My last two articles? They were about the differences between VoIP, WebRTC and the web.

By now, you probably recognize this:

If you’ve got some VoIP background, then you should know how WebRTC is different than VoIP.

If you’ve got a solid web background, then you should know why WebRTC development is different than web development.

When it comes to media, media flows and media related architectures, there seems to be an even bigger gap. People with VoIP background might have some understanding of voice, but little in the way of video. People with web background are usually clueless about real time media processing.

The result is that in too many cases, I see WebRTC architectures that make no sense in how they fit to what the vendor had in mind to create.

Want to learn more about media in WebRTC? Join this free webinar to see an analysis of a real case study I came across recently. What did the company had in mind to build and how they botched their architecture along the way.

Register and Grok media in WebRTC

Here are 4 reasons why media is so challenging:

#1 – Media is as Real Time as it Gets

Page load speed is important. People leave if your site doesn’t load fast. Google incorporates it as an SEO ranking parameter.

This is how it is depicted today:

So… every second counts. And the post slug is “your-website-design-should-load-in-4-seconds”.

From a WebRTC point of view, here’s what I have to say about that:

If I were given a full second to get things done with WebRTC I’d be… (fill in the blank)

Seriously though, we’re talking about real time conversations between people.

Not this conversation:

But the one that requires me to be able to hold a real, live one. With a person that needs to listen to me with his ears, see me with his eyes, and react back by talking to me directly.

400 milliseconds of a roundtrip or less (that’s 200 milliseconds to get media from your camera to the display on the other side) is what we’re aiming for. A full second would be disastrous and not really usable.

Real time.

For real.

#2 – Media Requires Bandwidth. Lots and Lots of Bandwidth

This one seems obvious but it isn’t.

Here’s a typical ADSL line:

Most people live in countries where this is the type of a connection you have into your home. You’ll have 20, 40 or maybe 100MB downlink – that’s the maximum bitrate you can receive. And then you’ll have 1, 2 or god forbid 3MB uplink – that’s the maximum bitrate you can send.

You see, most of the home use of the internet is based on the premise that you consume more than you generate. But with WebRTC, you’re generating media at all times (if it isn’t a live streaming type of a use case). And that media generation is going to eat on your bandwidth.

Here’s how much it takes to deliver this page to your browser (text+code, text+code+images) versus running 5 minutes of audio (I went for 40kbps) and 5 minutes of video (I went for 1Mbps). I made sure the browser wasn’t caching any page elements.

There’s no competition here.

Especially if you remember that with the page it is you who is downloading it, while with audio and video you’re both sending and receiving – it it is relentless as long as the conversation goes on the data use will grow.

Three more things to consider here:

  1. Usually, the assumption is that you need twice the bandwidth available than what you’re going to effectively send or receive (overheads, congestion and pure magi)
  2. You’re not alone on your network. There are more activities running on your devices competing over the same bandwidth. There can be more people in your house competing over the same bandwidth
  3. If you’re connecting over WiFi, you need to factor in stupid issues such as reception, air interferences, etc. These affect the effective bandwidth you’ll have as well as the quality of the network
#3 – Media is a Resource Hog

So it’s real time and it eats bandwidth. But that’s only half the story.

The second half involves anything else running on your device.

To encode and decode you’re going to need resources on that device.

CPU. Something capable. A usable hardware acceleration for the codecs to assist is welcomed.

Memory. Encoding and decoding are taxing processes. They need lots and lots of memory to work well. And also remember that the higher the resolution and frame rate of the video you’re pumping out – the higher the amount of memory you’ll be needing to be able to process it.

Bus. Usually neglected, there’s the device’s bus. Data needs to flow through your device. And video processing takes its toll.

Doing this in real time, means opening dedicated threads, running algorithms that are time sensitive (acoustic echo cancellation for example), synchronizing devices (lip syncing). This is hard. And doing it while maintaining a sleek UI and letting other unrelated processes run in the background as well makes it a tad harder.

So thinking of running multiple encoders and decoders on the device, working in mesh topologies in front of a large number of other users, or any other tricks you’re planning need to account for these challenges. And they need to put in focus the fact that browser vendors need to be aware of these topologies and use cases and take their time to optimize WebRTC to support them.

#4 – Media is Just… Different

Then there’s this minor fact of media just being so darn different.

It isn’t TCP, like HTTP and Websocket.

It requires 3 (!) different servers to just get a peer to peer session going (and they dare call it peer to peer).

Here’s how most websites would indicate their interaction with the browser:

And this is how a basic one would look like for WebRTC:

We’ve got here two browsers to make it interesting. Then there’s the web server and a STUN/TURN server.

It gets more complicated when we want to add some media servers into the mix.

In essence, it is just different than what we’re used to in the web – or in VoIP (who decided to do signaling with HTTP anyway? Or rely on STUN and TURN instead of placing an SBC?).

What’s Next?

These reasons of media being challenging? Real time, bandwidth-needy, resource hog and being different; That’s on the browser/client side only. Servers that need to process media suffer from the same challenges and a few more. One that comes to mind is handling scale.

So we’ve only touched the tip of the iceberg here.

This is why I created my Advanced WebRTC Architecture Course a bit over a year ago. It is a WebRTC training that aims at improving the WebRTC understanding of developers (and the semi-technical people around them).

In the coming weeks, I’ll be relaunching the office hours that run alongside the course for its third round. Towards that goal, I’ll be hosting a free webinar about media in WebRTC.

I’ll be doing something different this time.

I had an interesting call recently with a company moving away from CPaaS towards self development. The mistake they made was that they made that decision with little understanding of WebRTC.

Here’s what we’ll do during the webinar:

  1. Introduce the requirements they had
  2. Explain the architecture and technology stack they selected
  3. Show what went wrong
  4. Suggest an alternate route

Similar to my last launch, there will be a couple of time limited bonuses available to those who decide to enroll for the course.

Want to learn more about media in WebRTC? Join this free webinar to see an analysis of a real case study I came across recently. What did the company had in mind to build and how they botched their architecture along the way.

Register and Grok media in WebRTC

And if you’re really serious, enroll to my Advanced WebRTC Architecture Course.


The post Grokking Media in WebRTC (a free webinar for my WebRTC Course) appeared first on

PyFreeBilling – OSS Billing Platform

miconda - Mon, 09/11/2017 - 20:53
We want to highlight another project that uses Kamailio, which together with FreeSwitch, is part of PyFreeBilling, an open source billing platform targeting VoIP wholesale. It is released under AGPLv3.The project sources are hosted on Github at:The project has its own website at:While not tried yet here, the screenshots show a modern design and the list of features is quite impressive — next is an excerpt taken from project’s docs:
  • Customer add/modify/delete
    • IP termination
    • SIP authentication
    • Prepaid and/or postpaid
    • Realtime billing
    • Block calls on negative balance (prepaid) or balance under credit limit (postpaid)
    • Block / allow negative margin calls
    • Email alerts
    • Daily balance email to customer
    • Limit the maximum number of calls per customer and/or per gateway
    • Multiple contexts
    • Tons of media handling options
    • Powerfull ratecard engine
  • Provider add/modify/delete
    • Powerful LCR engine
    • Routing based on area code
    • CLI Routing
    • Routing decision based on quality, reliability, cost or load balancing (equal)
    • Limit max channels by each provider gateway
  • Extensive call and financial reporting screens (TBD)
  • CDR export to CSV
  • Customer panel
  • Design for scalability
Definitely worth a try!Enjoy! Thanks for flying Kamailio!PS. Should you develop a project related to Kamailio or be aware of such project, do not hesitate to contact us, we are glad to publish articles about them! 

Why Developing With WebRTC is Different than Web Development?

bloggeek - Mon, 09/11/2017 - 12:00

Soda and Mentos.

Last week I wrote about the difference between WebRTC and VoIP development. This week let’s see how WebRTC development is different from web development.

Let’s start by saying this for starters:

WebRTC is about Web Development

Well, mostly. It is more about doing RTC (real time communications). And enabling to do it over the web. And elsewhere. And not necessarily RTC.

WebRTC is quite powerful and versatile. It can be used virtually everywhere and it can be used for things other than VoIP or web.

When we do want to develop WebRTC for a web application, there are still differences – in the process, tools and infrastructure we will need to use.

Why is that?

Because real time media is different and tougher than most of the rest of the things you happen to be doing on the browser itself.

It boils down to this illustration (from last week):

So yes. WebRTC happens to run in the web browser. But it does a lot of things the way VoIP works (it is VoIP after all).

WebRTC dev != Web dev. And one of the critical parts is the servers we need to make it work. Join my free mini video WebRTC course that explains the server story of WebRTC.

Join the free server side WebRTC course

If you plan on doing anything with WebRTC besides a quick hello world page, then there’s lots of new things for you to learn if you’re coming from a web development background. Which brings me to the purpose of this article.

Here are 10 major differences between developing with WebRTC and web development:

#1 – WebRTC is P2P

Seriously. You can send voice, video and any other arbitrary data you wish directly from one browser to another. On a secure connection. Not going through any backend server (unless you need a relay – more on that in #6).

That triangle you see there? For VoIP that’s obvious. But for the web that’s magical. It opens up a lot of avenues for new types of services that are unrelated to VoIP – things like WebTorrent and Peer5; The ability to send direct private messages; low latency game controllers; the alternatives here are endless.

But what does this triangle mean exactly?

It means that you are not going to send your media through a web server. You are going to either send it directly between the browsers. Or you are going to send it to a media server – dedicated to this task.

This also means that a lot of the things you’ll need to keep track of and monitor don’t even get to your servers unless you do something about it to make it happen.

#2 – It isn’t all Javascript and JSON

Yes. I know last time I said it is all Javascript.

But if what you know is limited to Javascript then life is going to be a world of pain for you with WebRTC.

Media servers for example are almost always developed using C/C++ or Java. If you’ll need to debug them (and the serious companies do that), then you’ll need to understand these languages as well.

The second part is more JSON and less Javascript related – there’s one part of WebRTC that is ugly as hell but working. That’s the SDP that is used in the offer-answer negotiation process.

Besides being hard to interpret (different people understand SDP differently which later means they develop parsers and code for it differently), SDP is also hard to parse using Javascript. It isn’t built as a JSON blob, so the code to fetch a field or modify a field in SDP isn’t trivial (doable, but a pain).

#3 – There’s This Thing Called UDP

I guess this is the start of the following points as well, so here we go.

Today, the web is built on top of TCP. It started with HTTP. Moved to Websockets (also on top of TCP). And now HTTP/2 (also TCP).

There are attempts to allow for UDP type of traffic – QUIC is an example of it. But that isn’t there yet. And for most web developers that’s just under the hood anyway.

With WebRTC, all media is sent over UDP as much as possible. It can work over TCP if needed (I sent you to #6 didn’t I?), but we try to refrain for it – you get better media quality with UDP.

The table above shows the differences between UDP and TCP. This lies at the heart of how media is sent. We use unreliable connections with best effort.

#4 – Compromise is the Name of the Game

That UDP thing? It adds unreliability into the mix. Which also means that what you send isn’t what you get. Coupled with the fact that codecs are resource hogs, we get into a game of compromise.

In VoIP (and WebRTC), almost any decision we make to improve things in one axis will end up costing us in another axis.

Want better compression? Lose quality.

Don’t want to lose quality? Use more CPU to compress.

Want to lower the latency? Lose quality (or invest more CPU).

On and on it goes.

While CPUs are getting better all the time, and available bandwidth seems to be getting higher as well, our demand of our media systems is growing just as well. At times even a lot faster.

That ends up with the need to compromise.

All the time.

You’ll need to know and understand media and networking in order to be able to decide where to compromise and where to invest.

#5 – Best Effort is the Other Name

Here’s something I heard once in a call I had:

“We want our video quality to be a lot better than Skype and Hangouts”.

I am fine with such an approach.

But this is something I heard from:

  • 2 entrepreneurs with no experience or understanding if video compression
  • For a use case that needs to run in developing countries, with choppy cellular reception at best
  • And they assumed they will be able to do it all by themselves using WebRTC

It just doesn’t work.

WebRTC (and VoIP) are a best effort kind of a play.

You make do with what you get, trying to make the best of it.

This is why WebRTC tries to estimate the bandwidth available to it, and will then commence eating up all that available bandwidth to improve the video quality.

This is why when the network starts to act (packet loss), WebRTC will reduce the bitrate it needs and reduce the media quality in order to accommodate what is now available to it.

Sometimes these approaches work well. Other times not so well.

And yes. A lot of the end result will be reliant on how well you’ve designed and laid out your infrastructure for the service.

#6 – NAT Traversal Rules Your Life

Networks have NATs and Firewalls. These are nothing new, but if you are a web developer, then most likely they never did make life any difficult for you.

That’s because in the “normal” web, the browser will reach out to the server to connect to it. And being the main concept of our current day web, NATs and Firewalls expect that and allow this to happen.

Peer to peer communications, direct across browsers, as WebRTC operates. And with the use of UDP no less (again, something that isn’t usually done in the web browser)… these are things that firewalls and the IT personnel configuring them usually don’t need to contend with.

For WebRTC, this means the addition of STUN/TURN servers. Sometimes, you’ll hear the word ICE. ICE is an algorithm and not a server. ICE makes use and STUN and TURN. STUN and TURN are two protocols for NAT traversal, each using its own server. And usually, STUN and TURN servers are implemented in the same code and deployed using a single process.

WebRTC is doing a lot of effort to make sure its sessions will get connected. But at the end of the day, even that isn’t always enough. There are times when sessions just can’t get connected – whoever configured the firewall made sure of it.

#7 – Server Scaling is Ridiculous

Server scaling with WebRTC is slightly different than that of regular web.

There are two main reasons for that:

  1. The numbers are usually way smaller. While web servers can handle 5 digit connections or more, their WebRTC counterparts will often struggle with the higher end of 3 digits. There’s a considerable cost of hosting HD video and media server processing
  2. WebRTC requires statefulness. Severing a connection and restarting it will always be noticeable – a lot more than in most other web related use cases. This makes high availability, fault tolerance, upgrading and similar activities harder to manage with WebRTC

You’ll need to understand how each of the WebRTC servers work in order to understand how to scale it.

#8 – Bandwidth is Expensive

With web pages things are rather simple. The average web page size is growing year to year. We’ve got above 2.3MB in 2016. But that page is constructed out of different resources pulled from different servers. Some can be cached locally in the browser.

A 5 minute HD video at 2Mbps (not unheard of and rather common) will take up 75 MB during that 5 minutes.

If you are just doing 1:1 video calls with a 10% TURN relay factor, that can be quite taxing – running just 1,000 calls a day with an average of 5 minutes each will eat up 15 GB a day in your TURN server bandwidth costs. You probably want more calls a day and you want them running for longer periods of time as well.

Using a media server for group calling or recording makes this even higher.

As an example, at testRTC we can end up with tests that run into the 100’s of GBs of data per test. Easily…

When you start to work out your business model, be sure to factor in your bandwidth costs.

#9 – Geography is Everything for Media Delivery

For the most part, and for most services, you can get away with running your service off a specific data center.

This website of mine is hosted somewhere in the US (I don’t even care where) and hooked up to CDN services that take care of the static files. It has never been an issue for me. And performance is reasonable.

When it comes to real time live media, which is where WebRTC comes in, this won’t always do.

Getting data from New York to Paris can easily take 100 milliseconds or more, and since one of the things we’re striving for is real time – we’d like to be able to reduce that as much as we can.

Which gets us to the illustration above. Imagine two people in Paris having a WebRTC conversation that gets relayed through a TURN server in New York. Not even mentioning the higher possibility of packet losses, there’s clearly a degradation in the quality of the call just by the added delay of this route taken.

WebRTC, even for a small scale service, may need a global deployment of its infrastructure servers.

#10 – Different Browsers Behave Differently

Well… you know this one.

As a web developer, I am sure you’ve bumped into browsers acting differently with your HTML and CSS. Just recently, I tried to use <button> outside of a form element, only to find out the link that I placed inside it got ignored by Firefox.

The same is true for WebRTC. The difference is that it is a lot easier to bump into and it messes things up in two different levels:

  1. The API behavior – not all browsers support the exact same set of APIs (WebRTC isn’t really an official standard specification yet – just a draft; and browser implementations mostly adhere to recent variants of that draft)
  2. The network behavior – WebRTC means you communicate between browsers. At times, you might not get a session connected properly from one browser to another if they are different. They process SDP differently, they may not support the same codecs, etc.

As time goes by, this should get resolved. Browser vendors will shift focus from adding features and running after the specification towards making sure things interoperate across browsers.

But until then, we as developers will need to run after the browsers and expect things to break from time to time.

#11 – You Know More Than You Think

The majority of WebRTC is related to VoIP. That’s because at the end of the day, is it a variant of VoIP (one of many). This means that VoIP developers have a huge head start on you when it comes to understanding WebRTC.

The problem for them is that they have a different education than you do. Someone taught them that a call has a caller and a callee. That you need to be able to put a call on hold. To transfer the call. To support blind transfer. Lots and lots of notions that are relevant to telephony but not necessarily to communications.

You aren’t “tainted” in this way. You don’t have to unlearn things – so that nagging part of an ego telling you how things are done with VoIP – it doesn’t exist. I had my share of training sessions where most of my time was spent on this unlearning part.

This means that in a way you already know one important thing with WebRTC – that there’s no right and wrong in how sessions are created – and you are free to experiment and break things with it before coming to a conclusion of how to use it.

That’s powerful.

What’s Next?

If you have web development background, then there’s much you need to learn about how VoIP is done in order to understand WebRTC better.

WebRTC looks simple when you start with it. Most web developers will complain after a day or two of how complex it is. What they don’t really understand is how much more complicated VoIP is without WebRTC. We’ve been given a very powerful and capable tool with WebRTC.

Need to warm up to WebRTC? Try my free WebRTC server side mini course.

And if you’re really serious, enroll to my Advanced WebRTC Architecture Course.


The post Why Developing With WebRTC is Different than Web Development? appeared first on

Why Developing With WebRTC is Different than VoIP Development?

bloggeek - Mon, 09/04/2017 - 12:00

Water and oil?

Let’s start by saying this for starters:

WebRTC is VoIP

That said, it is different than VoIP in the most important of ways:

  1. In the ways entrepreneurs make use of it to bring their ideas to life
  2. In the ways developers yield it to build applications

Why is that?

Because WebRTC lends itself to two very different worlds, all running over the Internet: The World Wide Web. And VoIP.

And these two worlds? They don’t mix much. Beside the fact that they both run over IP, there’s not a lot of resemblance between them. Well, that and the fact that both SIP and HTTP has a 200 OK message.

Everyone is focused on the browser implementation of WebRTC. But what of the needed backend? Join my free mini video WebRTC course that explains the server story of WebRTC.

Join the free server side WebRTC course

If you ever developed anything in the world of VoIP, then you know how calls get connected. You’re all about ring tones and the many features that comprise a Class 5 softswitch. The turth of the matter is, that this kind of knowledge can often be your undoing when it comes to WebRTC.

Here are 10 major differences between developing with WebRTC and developing with VoIP:

#1 – You are No Longer in Control

With VoIP, life was simple. All pieces of the solution was yours.

The server, the clients, whatever.

When something didn’t work, you’d go in, analyze it, fix the relevant piece of software, and be done with it.

WebRTC is different.

You’ve got this nagging thing known as the “browser”.

4 of them.

And they change. And update. A lot.

Here’s what happened in the past year with Chrome and Firefox:

A version every 6-8 weeks. For each of them.

And these versions? They tend to change things in how the browsers change their behavior when it comes to WebRTC. These changes may cause services to falter.

These changes means that:

  1. You are not in control over the whole software running your service
  2. You are not in control of when pieces of your deployment get upgraded (browsers will upgrade without you having a say in it)

VoIP doesn’t work this way.

You develop, integrate, deploy and then you decide when to upgrade or modify things. With WebRTC that isn’t the case any longer.

You must continuously test against future browser versions (beta, unstable, Canary and nightly should become part of your vocabulary). You need to have the means to easily and quickly upgrade a production service – at runtime. And be prepared to do it rather frequently.

#2 – Javascript is King

My pedigree comes from VoIP.

I am a VoIP developer.

I did development, project management, product management and then been a CTO of a business unit where what we did was develop VoIP software SDKs that were used (and are still used) in many communication products.

I am a great developer. Really. One of the best I know. At least when it comes to coding in C.

VoIP was traditionally developed in C/C++ and Java.

With Javascript I know my way but by no means am I even an average developer. My guess is that a lot of VoIP engineers have a similar background to me.

WebRTC is all about Javascript.

In WebRTC, JavaScript is King
Click To Tweet

Yes. WebRTC has a Javascript API. But that’s half the story. Many of the backend systems written for use with WebRTC ends up using Node.js. Which uses Javascript.

WebRTC isn’t limited to Javascript. There are systems written in C, Java, Python, C#, Erlang, Dart and even PHP that are used. There are .Net systems. On mobile, native apps use Objective C, Swift or Java in their implementations of client-side WebRTC SDKs.

But the majority? That’s Javascript.

Three main reasons I can see for it:

  1. Fashion. Node.js is fashionable and new. WebRTC is also new, so there’s a fit
  2. Asynchronous. The signaling in WebRTC needs to be snappy and interactive. It needs to have a backend that can fit nicely with its model of asynchronous interactions and interfaces. Node.js offers just that and makes it easier to think of signaling on the frontend and backend at the same time. Which leads us to the third and probably most important reason –
  3. Javascript. You use it in the frontend and backend. Easier for developers to use a single language for both. Easier to shift bits and pieces of code from one side to the other if and when needed
#3 – A Big Island

VoIP is all about interoperability. A big happy family of vendors. All collaborating and cooperating. The idea is that if you purchase a phone from one vendor, you *should* be able to dial another vendor’s phone with it via a third vendor’s PBX. It works. Sometimes. And it requires a lot of effort in interoperability testing and tweaking. An ongoing arduous task. The end result though is a system where you end up testing a small set of vendors that are approved to work within a certain deployment.

VoIP and interoperability abhors the idea of islands. Different communication services that can’t connect to each other.

WebRTC is rather different. You no longer build one VoIP product or device that is designed to communicate with VoIP devices of other vendors. You build the whole shebang.

An island of sorts, but a rather big one. One where you can offer access through all browsers, operating systems and mobile devices.

You no longer care about interoperability with other vendors – just with interoperability of your service with the browsers you are relying on. It simplifies things some while complicating the whole issue of being in control (see #1 above).

#4 – It is Cloudy

It seems like VoIP was always mean to run in local deployments. There are a few cases where you see it deployed globally, but they aren’t many. Usually, there’s a geography that goes into the process.

This is probably rooted with the origins of VoIP – as a replacement / digital copy of what you did in telecom before. It also relates to the fact that the world was bigger in the past – the cloud as we know it today (AWS and the many other cloud providers that followed) didn’t really exist.

Skype is said to have succeeded so much as it did due to the fact that it had a great speech codec at the time that was error resilient (it had FEC built-in at a time companies conceptualized about bickering in the IETF and the ITU standard bodies about adding FEC in the RTP layer). It also had NAT traversal that just worked (again, when STUN and TURN were just ideas). The rest of the world? We were all happy enough to instruct customers to install their gatekeepers and B2BUAs in the DMZ.

Since then VoIP has evolved a lot. It turned towards the SBC (more on this in #10).

WebRTC has bigger challenges and requirements ahead of it.

For the most part, and with most deployments of WebRTC, there are three things that almost always are apparent:

  1. Deployments are global. You never know from where the users will be joining. Not globally and not their type of network
  2. Networks are unmanaged. This is similar to the above. You have zero control over the networks, but your users will still complain about the quality (just check out any of Fippo’s analysis posts)
  3. We deploy them on AWS. All the time. On virtual machines. Inside Docker containers. Layers and layers of abstraction. For a real time service. It it seems to work
#5 – Bring Your Own Signaling

VoIP is easy. It is standardized. Be it SIP, H.323, XMPP or whatever you bring to the table. You are meant to use a signaling protocol. Something someone else has thought of in the far dark rooms in some standards organization. It is meant to keep you safe. To support the notion and model of interoperability. To allow for vendor agnostic deployments.

WebRTC did away with all this, opting to not have a signaling protocol at all out of the box.

Some complain about it (mostly VoIP people). I’ve written about it some 4 years ago – about the death of signaling.

With WebRTC you make the decision on what signaling protocol you will be using. You can decide to go for a standards based solution such as SIP over WebSocket, XMPP over BOSH or WebSocket – or you can use a newly created signaling protocol invented only for your specific scenario – or use whatever you already have in your app to signal people.

As with anything in WebRTC, it opens up a few immediate questions:

  1. Should you use a standards based signaling protocol or a proprietary one?
  2. Should you built it on your own from scratch or use a third party framework for it?
  3. Should you host and manage it on your own or use it as a service instead?

All answers are now valid.

#6 – Encryption and Privacy are MANDATORY

With VoIP, encryption was always optional. Seldom used.

I remember going to these interoperability events as a developer. The tests that almost never really succeeded were the ones that used security. Why? You got to them last during the week long event, and nobody got that part quite the same as others.

That has definitely changed over the years, but the notion of using encryption hasn’t. VoIP products are shipped to customers and deployed without encryption. The encryption piece is an optional configuration that many skip. Encryption makes it hard to use wireshark to understand what goes in the network, it takes up CPU (not much anymore, but still conceptually it is), it complicates things.

WebRTC on the other hand, has only encryption configured into it. No way to use it with clear RTP. even if you really really want to. Even if you swear all browsers and their communications run inside a secure network. Nope. can’t take security out of WebRTC.

#7 – If it is New, WebRTC Will be Using it

When WebRTC came out, it made use of the latest most recent RFCs that were VoIP related in the media domain.

Ability to bundle RTP and RTCP on the same stream? Check.

Ability to multiplex audio and video on the same stream? Check.

Ability to send FIR commands over RTCP and not signaling? Check.

Ability to negotiate keys over DTLS-SRTP instead of SDES? Check.

There are many other examples for it.

And in many cases, WebRTC went to the extreme of banning the other, more common, older mechanisms of doing things.

VoIP was always made with options in mind. You have at least 10 different ways in the standard to do something. And all are acceptable.

WebRTC takes what makes sense to it, throwing the rest out the window, leaving the standard slightly cleaner in the end of it.

Just recently, a decision was made about supporting non-multiplexed streams. This forced Asterisk and all of its users to upgrade.

VoIP and SIP were never really that important to WebRTC. Live with it.

#8 – Identity Management and Authorization are Tricky

There’s no identity management in WebRTC.

There’s also no clear authorization model to be heard of.

Here’s a simple one:

With SIP, the way you handle users is giving them usernames and passwords.

The user clicks that into the client and this gets used to sign up to the service.

With regular apps, it is easy to set that username/password as your TURN credentials as well. But doing it with WebRTC inside a browser opens up a world of pain with the potential of harvesting that information to piggyback on your TURN servers, costing you money.

So instead you end up using ephemeral passwords in TURN with WebRTC. Here’s an explanation how to do just that.

In many other cases, you simply don’t care. If the user already logged into the page, and identified and authenticated himself in front of your service, then why have an additional set of credentials for him? You can just as easily piggyback a mechanism such as Facebook connect, Twitter, LinkedIn or Google accounts to get the authentication part going for you.

#9 – Route. Don’t Mix

If you come from VoIP, then you know that for more than two participants in a call you mix the media. You do it usually for audio, but also for the video. That’s just how things are (were) done.

But for WebRTC, routing media through an SFU is how you do things.

It makes the most sense because of a multitude of reasons:

  1. For many use cases, this is the only thing that can work when it comes to meeting your business model. It strikes that balance between usability and costs
  2. This in turn, brings a lot of developers and researchers to this domain, improving media routing and SFU related technologies, making it even better as time goes by
  3. In WebRTC, the client belongs to the server – the server sends the client as HTML/JS code. With the added flexibility of getting multiple media streams, comes an added flexibility to the UI’s look and feel as well as behavior

There are those who are still resistant to the routing model. When these people have a VoIP pedigree, they’ll lean towards the mixing model of an MCU, calling it superior. It will usually cost 10 times or more to deploy an MCU instead of an SFU.

Be sure to know and understand SFUs if you plan on using WebRTC.

#10 – SBCs are Useless

Or at least not mandatory anymore.

Every. SBC. vendor. out. there. is. adding. WebRTC.

And I get it. If you’re building an SBC – a Session Border Controller – then you should also make sure it supports WebRTC so all these pesky people looking to get access through the browser can actually get it.

An SBC was an abomination added to VoIP. It was a necessary evil.

It served the purpose of sitting in the DMZ, making sure your internal network is protected against malicious VoIP access. A firewall for VoIP traffic.

Later people bolted on that SBC the ability to handle interoperability, because different vendor products never really worked well with one another (we’ve already seen that in #3). Then transcoding was added, because we could. And then other functions.

And at some point, it was just obvious to place SBCs in VoIP infrastructure. Well… WebRTC doesn’t need an SBC.

VoIP needs an SBC that handles WebRTC. But if you’re planning on doing a WebRTC based application that doesn’t have much of VoIP in it, you can skip the SBC.

#11 – Ecosystem Created by the API and Not the Specification

Did I say 10 differences? So here’s a bonus difference.

Ecosystems in VoIP are created around the network protocol.

You get people to understand the standard specification of the network protocol, and from there you build products.

In WebRTC, the center is not the network protocol (yes, it is important and everything) – it is the WebRTC APIs. The ones implemented in the browsers that enable you to build a client on top. One that theoretically should run across all browsers.

That’s a huge distinction.

Many of the developers in WebRTC are clueless about the network, which is a shame.  On the other hand, many VoIP developers think they understand the network but fail to understand the nuanced differences between how the network works in VoIP and in WebRTC.

What’s Next?

If you have VoIP background, then there are things for you to learn when shifting your focus towards WebRTC. And you need to come at it with an open mind.

WebRTC seems very similar to VoIP – and it is – because it is VoIP. But it is also very different. In the ways it is designed, thought of and used.

Knowing VoIP, you should have a head start on others. But only if you grok the differences.

Need to warm up to WebRTC? Try my free WebRTC server side mini course.

And if you’re really serious, enroll to my Advanced WebRTC Architecture Course.


The post Why Developing With WebRTC is Different than VoIP Development? appeared first on

Kamailio v5.0.3 Released

miconda - Fri, 09/01/2017 - 21:00
Kamailio SIP Server v5.0.3 stable is out – a minor release including fixes in code and documentation since v5.0.2. The configuration file and database schema compatibility is preserved, which means you don’t have to change anything to update.Kamailio v5.0.3 is based on the latest version of GIT branch 5.0. We recommend those running previous 5.0.x or older versions to upgrade. There is no change that has to be done to configuration file or database structure comparing with the previous release of the v5.0 branch.Resources for Kamailio version 5.0.3Source tarballs are available at:Detailed changelog:Download via GIT: # git clone kamailio
# cd kamailio
# git checkout -b 5.0 origin/5.0Relevant notes, binaries and packages will be uploaded at:Modules’ documentation:What is new in 5.0.x release series is summarized in the announcement of v5.0.0:Thanks for flying Kamailio!

How to capture & replay WebRTC video streams with video_replay (Stian Selnes)

webrtchacks - Thu, 08/31/2017 - 15:41

Decoding video when there is packet loss is not an easy task.  Recent Chrome versions have been plagued by video corruption issues related to a new video jitter buffer introduced in Chrome 58. These issues are hard to debug since they occur only when certain packets are lost. To combat these issues, has a […]

The post How to capture & replay WebRTC video streams with video_replay (Stian Selnes) appeared first on webrtcHacks.

Kamailio Presentation At ClueCon 2017

miconda - Tue, 08/22/2017 - 21:59
Fred Posner, our big friend (and baker from Florida), participated to ClueCon Conference 2017 and gave a presentation about Kamailio SIP Server. The slides deck is available at:You can find some good hints and tips about using Kamailio for building intelligent SIP routing.As usual, we would like to thank for spending time and financial resources for promoting Kamailio. Should you present at a large world wide event or small meetup in your area and have some notes about Kamailio, we definitely appreciate it a lot and we are more than happy to host a copy of the slides on our events directory:Just get in touch with us!Thank you for flying Kamailio!

Taking a Breather. Be Back in September

bloggeek - Mon, 08/21/2017 - 12:30

See you in September.

Time for some downtime for me.

Not from work – got too many projects going on at the moment – updating my course, testRTC and some interesting customer projects I am involved with. I am also working on an offering around APIs. More on that later.

This means – no new writing here for the next couple of weeks.

See you all once I am back.

In the meantime, if you have any questions or needs around the things I write about, feel free to contact me. I’ll gladly help you find your way around this tech (and even focus my writing in the areas you are interested in).

Until September

The post Taking a Breather. Be Back in September appeared first on

How do you Upgrade Your WebRTC Media Servers?

bloggeek - Mon, 08/14/2017 - 12:00

I say it doesn’t matter what the technique is as long as you go through the motion of upgrading your WebRTC Media Servers…

Here’s the thing. In many cases, you end up with a WebRTC deployment built for you. Or you invest in a project until its launch.

And that’s it.

Why Upgrade WebRTC Media Servers?

With WebRTC, things become interesting. WebRTC is still a moving target. Yes. I am promised that WebRTC 1.0 will be complete and published by the end of the year. I hear that promise since 2015. It might actually happen in 2017, but it seems browser vendors are still moving fast with WebRTC, improving and optimizing their implementations. And breaking stuff at times as they move along.

Add to that the fact that media servers are complex, and they have their own fixes, patches, security updates, optimizations and features – and you find yourself with the need to upgrade them from time to time.

Upgrade as a non-functional feature is important for your WebRTC requirements. I just updated my template, so you don’t forget it:

Download the WebRTC Requirements How To

I’ll take it a bit further still:

  1. With WebRTC, the browser (your client) will get upgraded automatically. It is for your own safety This in turn, may force you to upgrade the rest of your infrastructure; and the one prone the most?
  2. Your WebRTC media server needs to be upgraded. First to keep pace with the browsers, but also and not less important, to improve; but also
  3. The signaling server you use for WebRTC. That one may need some polish and fine tuning because of the browser. It may also need to get some care and attention – especially if and when you start expanding your service and need to scale out – locally or geographically
  4. Your TURN/STUN servers. These tend to go through the least amount of updates (and they are also relatively easy to upgrade in production)

Great. So we need to upgrade our backend servers. And we must do it if we want our service to be operational next year.

Talking Production

But what about production system? One that is running and have active users on it.

How do you upgrade it exactly?

Gustavo García‏ in a recent tweet gave the techniques available and asked to see them by popularity:

Just curious about how do you upgrade your #WebRTC mediaservers?

— Gustavo García (@anarchyco) August 4, 2017

I’d like to review these alternatives and see why developers opt for “Draining first”. I’ll be using Gustavo’s naming convention here as well. I will introduce them in a different order though.

#1 – Immediate Kill+Reconnect

This one is the easiest and most straightforward alternative.

If you want to upgrade WebRTC media servers, you take the following steps:

  1. Kill the existing server(s)
  2. Upgrade their software (or outright replace their machines – virtual or bare metal)
  3. Reconnect the sessions that got interrupted – or don’t…

This is by far the simplest solution for developers and DevOps. But it is the most disruptive for the users.

That third step is also something of a choice – you can decide to not reconnect existing sessions, which means users will now have to reconnect on their own (refresh that web page or whatever), or you might have them reconnected, either by invoking it from the server somehow or having the clients implement some persistency in them to make them automatically retry on service interruption.

This is also the easiest way to maintain a single version of your backend running at all times (more on that later).

#2 – Active/Passive Setup

In an active/passive setup you’ll have idle machines sitting and waiting to pick up traffic when the active WebRTC media servers are down (usually for whatever reasons and not only on upgrades).

This alternative is great for high availability – offering uptime when machines or whole data centers break, as the time to migrate or maintain service continuity will be close to instantaneous.

The downside here is cost. You pay for these idle machines that do nothing but sit and wait.

There are variations of this approach, such as active-active and clustering of machines. Not going to go in the details here.

In general, there are two ways to handle this approach:

  1. Upgrade the passive machines (maybe even just create them just before the upgrade). Once all are upgraded, divert new traffic to them. Kill the old machines one by one as the traffic on them whanes
  2. Employ rolling upgrade, where you upgrade one (or more) machines each time and continue to “roll” the upgrade across your infrastructure. This will reduce your costs somewhat if you don’t plan on keeping 1:1 active/passive setup at all times

(1) above is the classic active/passive setup. (2) is somewhat of an optimization that gets more relevant as your backend increases in its size – it is damn hard to replace everything at the same time, so you do it in stages instead.

Note that in all cases from here on you are going to have at least two versions of your WebRTC media servers running in your infrastructure during the upgrade. You also don’t really know when the upgrade is going to complete – it depends on when people will close their ongoing sessions.

In some ways, the next two cases are actually just answering the question – “but what do we do with the open sessions once we upgrade?”

#3 – Sessions Migration First

Sessions migration first means that we aren’t going to wait for the current sessions to end before we kill the WebRTC media server they are on. But we aren’t going to just immediately kill the session either (as we did in option #1).

What we are going to do, is have some means of persistency for the sessions. Once a new upgraded WebRTC media server machine is up and running, we are going to instruct the sessions on the old machine to migrate to the new one.


Good question…

  • We can add some control message and send it via our signaling channel to the clients in that session so they’ll know that they need to “silently” reconnect
  • We can have the client persistently try to reconnect the moment the session is severed with no explanation
  • We can try and replicate the machine in full and have the load balancer do the switchover from old to new (don’t try this at home, and probably don’t waste your time on it – too much of a headache and effort to deal with anyways)

Whatever the technique, the result is that you are going to be able to migrate rather quickly from one version to the next – simply because once the upgrade is done, there won’t be any sessions left in the old machine and you’ll be able to decommission it – or upgrade it as well as part of a rolling upgrade mechanism.

#4 – Draining First

Draining first is actually draining last… let’s see why.

What we are going to do here is bring up our new upgraded WebRTC media servers, route all new traffic to them and… that’s about it.

We will keep the old machines up and running until they drain out of the sessions that they are handling. This can take a couple of minutes. An hour. A couple of hours. A day. Indefinitely. Depending on the type of service you have and how users interact with it will determine how long on average it will take for a WebRTC media server to drain its sessions with no service interruption.

A few things to ponder about here (some came from the replies to that original tweet):

  • WebRTC media servers can’t hold too much traffic (they don’t scale to millions of sessions in parallel)
    • With a large service, you can easily get to hundreds of these machines
    • Having two installations running in parallel, one with the new version and one with the old will be very expensive to operate
    • The more servers you’ll have, the more you’ll want to practice a rolling upgrade, where not all servers are upgraded at the same time
  • You can have more than two versions of the WebRTC media server running in parallel in your deployment. Especially if you have some really long lived sessions
  • You can be impatient if you like. Let session drain for an hour. Or two. Or more. And then kill what’s left on the old WebRTC media server
  • Media servers might be connected to other types of services – not only WebRTC clients. In such a case, you’ll need to figure out what it means to kill long lived sessions – and maybe decouple your WebRTC media server to further smaller servers
Why Most Developers Lean Towards Draining First?

Gustavo’s poll garnered only 6 answers, but they somehow feel right. They make sense from what I’ve seen and heard from the discussions I’ve had with many vendors out there.

And the reasons for this are simple:

  1. There’s no additional development on the client or WebRTC media servers. It is mostly DevOps scripts that need to reroute new incoming traffic and some monitoring logic to decide when to kill an empty old WebRTC media server
  2. There’s no service disruption. Old sessions keep running until they naturally die. New sessions get the upgraded WebRTC media servers to work on
What’s next?

If you are planning on deploying your own infrastructure for WebRTC (or have it outsourced), you should definitely add into the mix the upgrade strategy for that infrastructure.

This is something I overlooked in my WebRTC Requirements How To – so I just added it into that template.

Need to write requirements for your WebRTC project? Make sure you don’t miss out on the upgrading strategy in your requirements:

Get my WebRTC Requirements How To

The post How do you Upgrade Your WebRTC Media Servers? appeared first on

ACC – SQL Define Removed And Diameter Code Relocated

miconda - Wed, 08/09/2017 - 18:23
The ACC module (accounting) in Kamailio got a bit of clean up, therefore be aware of following changes:
  • (1) the define conditions on SQL_ACC were removed — this was enabled for more than 10 years and only made the code look complex and hard to follow up its logic.
  • (2) the code related to DIAMETER accounting was relocated to acc_diameter (new) module. It was a consistent size of code that was not enabled for sooo… long. It is now a dedicated module, similar to acc_radius. The diameter accounting code, even a new module now, is in the same stage, compiling but not tested, in pair with auth_diameter module, it may work, but very likely not.
In summary, what’s important for those using the acc module — it offers the same functionality as it was enabled by default in the past 10 years or more: writing accounting records to syslog and sql databases — only the unused code was relocated.The acc module is now slimmer, only with the code that it needs, therefore easier to maintain and enhance for the future. For any issue, as usual open a report on Github project portal.Thanks for flying Kamailio!

Is WebRTC Safe?

bloggeek - Mon, 08/07/2017 - 12:00


In recent years, we’ve seen a lot of hysteria going on around WebRTC. Mainly it being unsafe to use. So much so, that there are tutorials out there explaining how to disable it in every conceivable browser out there.

This reminds me all of the past (and present?) hysteria around running JavaScript code inside the browser – and again – how to disable it.

If you are developing a WebRTC application AND you care about the security of your service and the privacy of your users, make sure to review my WebRTC Security Checklist.

Get the WebRTC Security Checklist

Why is WebRTC Perceived as Dangerous?

WebRTC is a real time communication technology that is embedded in the browser. It can access your camera and your microphone as well as share the contents of your screen. As such, it enables a browser (and web developers) access to a lot more resources on the device of an end user.

This boils down to two main risks:

  1. Your data can be stolen by nefarious people
  2. Your privacy can be breached by knowing more about your device
1. Your data can be stolen by nefarious people

Here are a few scary ideas:

  • If I can access your microphone, I’ll be able to record all of your conversations
  • If I can access your camera, I’ll be able to snoop on you. Maybe take a nice recording of your intimate moments
  • If I can access your screen remotely, I’ll be able to record what you’re doing. Maybe even control your mouse and keyboard remotely while at it?

With all the goodness WebRTC brings, who wants to be spied on by his own device?

Now, that said, we also need to understand two things here:

  1. The browser isn’t the only game in town to gaining this access to your data and actions
  2. There are measures put in place to limit the ability to conduct in such activities
2. Your privacy can be breached by knowing more about your device

This one I guess is mostly about tracking you over the internet. Which is what ad networks are doing most of the time.

WebRTC gives access to more elements that are unique, which makes fingerprinting of the device (and you) a lot more accurate. Or so they say.

The main concern here are around the exposure of private IP addresses to web servers. There are many out there who see these “IP leaks” as a serious threat. for most of humanity, I believe it isn’t, which is why I’ll gladly publish my private IP address here:

There are other, more nuanced ways in which WebRTC can be used for fingerprinting, such enumerating the device list as part of your device’s unique identity. Which is a concern, until you review the  accuracy of fingerprinting without even using WebRTC. Here are two resources for you to enjoy:

  1. Panopticlick – EFF’s fingerprinting check up ad research. If you are not unique – comment below – I have a feeling your browser is as unique as mine. Their TL;DR? Disable JavaScript (which will be too much work) or use a more “common” browser. I am NOT making this up:
  2. Fingerprintjs2 – one of the many libraries available to fingerprint your browser. It doesn’t use WebRTC, although there’s an “intent” in there to add support to it

In this area, Apple with their new WebRTC support in Safari is leading the way in maintaining privacy. You can read about it in a recent article in the WebKit blog. Look specifically on the sections titled “ICE Candidate Restrictions” and “Fingerprinting”.

Why is WebRTC the Safest Alternative?

If you are a developer looking for a real time communications technology to use in your application, or you are an IT person trying to decide what to deploy in your company, then WebRTC should be your first alternative. Always.

Here’s why.

1. Browser vendors take care security seriously

There are 4 major browser vendors: Apple, Google, Microsoft and Mozilla

All of these vendors are taking care of security and patching their browsers continuously. In some cases, they even roll out new versions at breakneck speeds of 6-8 weeks, with security patches in-between.

If a security threat is found, it gets fixed fast.

While many other vendors can say that they are fixing and patching security threats fast – do they deploy them fast? Do they have the means to do so?

Since browsers get updated and upgraded so frequently, and to hundreds of millions of users, getting a security patch to the field happens rather fast. Philipp Hancke showed and explained some Here are some browser upgrade stats last year. This is from real users conducting sessions. I asked him to share a more recent graph, and here’s what they’ve had in the last two large browser version cycles for Chrome:

Look at the point in time when each Chrome version got ramped up from less than 30% to over 80% in a span of a couple of days. Chrome 59 is especially interesting. Also note that there are at most 2 versions of Chrome out there with over 95%+ of use. Since they routinely do it, patching and deploying security issues is “easy”.

The only other vendors who can roll out and deploy patches so fast? Operating system vendors (again we end up with Apple, Google and Microsoft), and application developers, through mobile app stores (which sums up to Apple and Google).

Nothing comes close to it.

Takeaway: Assume there will be security breaches or at the very least the need to patch security issues. Which means you should also plan for upgrade policies. Browsers are the best at upgrading these days.

2. You don’t need to redeploy the client software

Lets face it – most users don’t disable the automatic update policy of their browsers. If you’re even remotely interested in security, you shouldn’t disable automatic update policies of ANYTHING.

Manual updates bring with them a world of pain:

(a) When do you upgrade?

Here’s the thing.

How do you know an upgrade is in order? Are you on the list of threat alerts of all the software and middleware you are using in your company? Once a threat is announced and a patch is available – do you immediately upgrade?

When we leave this decision to a human, then he might just miss the alert. Or fail to upgrade. Or decide to delay. Just because… he’s human.

Most software can get updated, but usually won’t do it automatically or won’t do it silently. And automation in this area that is done externally, such as the Kaspersky Software Updater. It works, but up to a point and it also adds another headache to contend with and manage.

If a browser does that for you freely, why not use it?

(b) What if this fails?

Did you ever get a software update to fail?

What about doing that in a company with 100+ employees?

If software fails to update 1% of the time, it means that every time you update something – someone will complain or just fail to update, making you revert back to a manual process.

There are tons of reasons why these processes fail, and most are due to the fact that we all have different firmware, software and device drivers on our machines (see fingerprinting above). This fact alone means that if a software isn’t running on millions of devices already, it will fail for some. I’ve seen this too many times when the company I worked for developed a plugin for browsers.

Anyone not using WebRTC and deploying via software installation will cause you grief here. If this is only in front of employees, then maybe that’s fine. But often times this is also with end user devices – and you don’t want to mess there.

Browser upgrades will fail a lot less often, so better use that and just make use of WebRTC instead of rolling your own proprietary solution.

(c) What about edge cases?

You can’t control your employees and their whereabouts for your upgrades.

People working from home.

People traveling abroad.

People using BYOD and… not having tight enterprise policies on their own home laptop.

If you want less headache in this department, then again – using WebRTC will give you peace of mind that security patches get updated.


Look at it this way, the engine of WebRTC will always stay secure when you rely on browser and browser updates.

You have control over the backend (or rely on a cloud service provider with an SLA you are paying for exactly for this reason). The backend gets updated for security patches all the time (or as much as you care). The browsers get updated automatically so you can think less about it.

Using proprietary software or legacy VoIP vendor software means you’ll need to patch both backend and client software. This is harder to do and maintain – and easier to miss.

3. WebRTC has inherent security measures in place

This should probably be the first reason…

One thing you hear many complain about is questioning why WebRTC is always encrypted. Somehow, developers decided that sending media in the clear is a good thing. While there might be some reasons to do that, most of them are rather irrelevant for something like WebRTC, meant to be used on unmanaged networks.

WebRTC took the approach of placing its security measures first. This means:

  1. There’s no way send media in the clear. Everything is always encrypted. In other VoIP solutions, you can configure encryption on and off (if encryption is even there)
  2. There’s no way to use WebRTC in websites that aren’t served over HTTPS. This means WebRTC forces developers to use secure connections for signaling – and for the whole site. And no. Using iframes won’t work either
  3. Users are asked to allow access to the their media inputs. Each browser handles this one slightly differently, and these models also changes over time, but suffice to say that the idea here is again – to balance privacy of the users and the usability of the service

Me? I’d rather rely on the security measures placed in browsers. These go through the scrutiny of lots of people who are all too happy to announce these security flaws. Software from vendors that is specific to communications? A lot less so.

And yes. This isn’t enough. WebRTC is the building block used to build an application. A lot of what goes to the security of the finished service will rely on the developers who developed the application – but at least they got a head start by using WebRTC.

Ads and WebRTC

There’s an angle that isn’t much discussed about WebRTC. And that’s the uses it finds in the ad business.

The Bad

Two main scenarios that I’ve seen here:

  1. Fingerprinting. You get better means to know more about who the user behind the browser is
  2. Serving ads themselves. Theoretically, you might be able to serve ads via WebRTC, and that at the moment has the potential to circumvent ad blockers
The Good

There’s the second part of it. When ads are served today, the companies paying for these ads being served like to get their ROI. On the other hand, there are those who would like the money spent on ads to be wasted. So they use bots to click ads. Probably by automating selenium processes.

This is similar in concept to the “I am not a robot” type of entry measures and captchas out there. WebRTC gives another layer of understanding about the user and its behavior – and enables us to know if he is a human or a bot inside that browser. And yes. We can use it for things other than ad serving.

Where do we go from here?

There are two main approaches to security:

  1. Security by obscurity – relying on people not knowing the protocol in place. It works great when you’re small and insignificant, so no one is going to care about you anyway. It falls apart when you become popular
  2. Kerckhoffs’ principle – a system needs to be secure even when we know everything about the system. It works best when many people scrutinize, analyze and try to hack such systems, making it better and more robust through time

WebRTC is in the second category (the first one – security by obscurity – is often criticized for being unsecure by nature).

With all the resources put into WebRTC from all angles, security is also being taken care of and not left behind.

WebRTC is safe to adopt as developers. IT and security people in the enterprise shouldn’t shy away from it either – just make sure the vendor you pick did a decent job with his implementation.

Are you doing what it takes to improve the security of your WebRTC application?

Get the WebRTC Security Checklist

The post Is WebRTC Safe? appeared first on

Research On VoIP Fraud Using Kamailio As Sensor

miconda - Tue, 08/01/2017 - 14:21
Konstantin Tumalevich has posted an article via GitHub about his research done on VoIP fraud using Kamailio as a sensor, along with other VoIP applications such as Asterisk.Some interesting facts extracted from the article:For research, I created honeypot what mimics vulnerable PBX.For emulation, I used Kamailio nodes that send any calls to termination node and answers to OPTIONS and REGISTER.For every INVITE I recorded From, To, UA, Call-ID, IP and call time.Termination node has Kamailio with Flask app for preprocessing calls and Asterisk for topology hiding when calls sent to PSTN.All calls with a cost of more than 2 cents per minute were rejected with code 486.I used 4 sensor nodes located in NL, DE, SG and NYC.For 18 days, 254805 INVITE were collected from 296 different IP’s. On average, 860 INVITEs were received from an IP.Reports about top source IPs, countries of origin and the operator as well as related graphs can be found in the conclusions of the research. Few hints are also provided about how to protect better.You can read the entire article at:Enjoy!Thanks for flying Kamailio!

Sound Gurus Finding a Home in WebRTC

bloggeek - Mon, 07/31/2017 - 12:00

When it comes to different verticals and market niches, it seems like WebRTC can fit anywhere.

6 years in, and there are many who still question if WebRTC is the way to go with their use case. This is one of the reasons why I started the WebRTC Dataset. The idea behind it all was to showcase all the variations and services where WebRTC is being used.

Here’s an example for you.

Musicians of all kinds make use of WebRTC. They have services today that are geared towards their specific needs. And I am not talking only about replacing Skype with a marketplace or a searchable directory of experts that can help you take private guitar lessons online.

When I bumped into Profound Studio, I knew this is an area I’d like to write a bit more about, so here it goes.

What I will be doing in this article, is go over some of the vendors found in the WebRTC Dataset, collected over the years, who are playing a role in the sound/music industry in one way or another.

I won’t be picking favorites here – my own experience with music is rather dull – I like to hear music just like anyone else, but I don’t consider myself an expert or a fan of anything really. This means that we’ll be going in alphabetic order of the vendors.

Care 2 Rock

Care 2 Rock is that we-teach-guitar-lessons use case with a twist.

The basic premise is having teaching music lessons of any kind online, through a video call. The twist is that this is a paid/voluntary act on the side of the teacher, who ends up teaching and mentoring a foster care kid in his community.

Profound Studio

Profound Studio connects musicians with recording experts.

This is a marketplace for professionals – not for hobbyists. You can run live classes there or do consultation calls.


sofasession is all about musicians making music together online. The majority of it is done asynchronously, where each musician contributes and edits tracks of the final masterpiece, but they don’t need to be live together at the same time. And still, this kind of a use case can use WebRTC.

Here’s a job posting they had from two years ago:

We will use Kurento as media server and extending the service for multitrack mixing and reducing latency by developing latency reducing algorithms for serving content to clients connected via the webRTC protocol.

For the layman, handling audio in realtime in the browser to handle that mixing module that’s inside sofasession requires low latency. The best way to get there is to have something like WebRTC manage it – we are talking about real time here.

I am not sure if and how far they went with their WebRTC support. They do support live jam sessions, but there’s a need to download dedicated software for that. It does use UDP to work, so there still might be some WebRTC in there.


Soundtrap is similar to sofasessions. It too focuses on musicians collaborating online.

Based in Stockholm, where some of the Google WebRTC team are located, even got it to appear at Google I/O in 2014:


StreetJelly is about live performances. It allows artists to stream their music live to a global audience.

At the moment, performing and viewing is free. Viewers can tip performers if they want.

On the technical side, StreetJelly uses HTML5 video playback for the viewers and either Flash (now dead) or WebRTC (the new method for StreetJelly) to be able to broadcast the performances. They explain this further here.

Shots in the dark

Other vendors such as and came and went.

As with any set of startups, the vendors in this space don’t always succeed.

How will others fair? Time will tell.

The Appeal

Music and WebRTC. There’s an appeal there.

VoIP was crap most of the time up until recently. There were two main reasons for it:

  1. The selection of voice codecs, with the dominant ones being narrowband codecs like G.711 or the G.729. When you did get a better sounding codec, it was either protected by patents, not suitable for real time or just stuck in wideband but still focusing on speech and not music
  2. These codecs aren’t usually error resilient. The moment you introduce packet loss (and these happen regularly), the audio quality suffers. So something had to be done in that front

WebRTC comes with Opus “out of the box”. A wideband codec suitable for music – not only speech, which is royalty free, low latency and error resilient. To top it all – it is mandatory in WebRTC and one of only two such codecs (the other one being the ridiculously crappy G.711). What’s not to like as a musician?

Why is this important?

Well… here’s the kicker.

None of it is new.

VoIP and video calling could have done this all before WebRTC.

But it didn’t.


Costs. Barriers of entry. Finding talent.

WebRTC solves all that, which is why I categorize all of these vendors and many others as WebRTC vendors.

They don’t care about WebRTC as a technology – for them it is just means to an end, which is just fine.

But what about you?

Want to learn more about a specific market niche where real time communications be of use? Want to instantly find who’s there already and what they are doing?

You’d better take a look at the WebRTC Dataset. Especially today, before the earlybird discount ends.

Get access to the WebRTC Dataset

The post Sound Gurus Finding a Home in WebRTC appeared first on

WebRTC Externals – the cross-browser WebRTC debug extension

webrtchacks - Fri, 07/28/2017 - 12:30

I am a big fan of Chrome’s webrtc-internals tool. It is one of the most useful debugging tools for WebRTC and when it was added to Chrome back in 2012 it made my life a lot easier. I even wrote a lengthy series of blog post together with Tsahi Levent-Levi describing how to use it […]

The post WebRTC Externals – the cross-browser WebRTC debug extension appeared first on webrtcHacks.

ClueCon 2017

miconda - Mon, 07/24/2017 - 12:52
As every August for more than a decade, the ClueCon conference takes place again in Chicago, USA, during August 7-10, 2017. Mainly organised by the people behind FreeSwitch project, ClueCon is among those events where you can meet a large group of experienced people with open source realtime communication technologies.Kamailio will be present with a talk by Fred Posner, one of our very active advocates of the project in North America and not only. His presentation is scheduled for Wednesday, August 9, at 10:45am:Besides Fred, you will be able to meet other relevant members of Kamailio project or friends from the VoIP world! If you haven’t checked the event so far, do it very soon and consider to register, no much time left and ClueCon is always worth attending! Read moreabout the event at:Enjoy!Thank you for flying Kamailio!

Drilling into the WebRTC Dataset

bloggeek - Mon, 07/24/2017 - 12:00

Knowledge=Power. Which is why the WebRTC Dataset might be just what you need.

A Quick History Lesson

You see numbers flying around about WebRTC all the time. One of them is the number of vendors using WebRTC. 1,200 might sound familiar in that context. Well… it comes from the WebRTC Dataset that I am maintaining.

It all started ages ago. I think it was Alan Quayle who made a shortlist of the companies that were using WebRTC that he knew about. That was somewhere in 2012. Which made me start my own Excel sheet. Which was then converted into a Google sheet. Which was then converted into a whole operation of how to find, catalog and update a dataset.

The reason? One of the main companies who are influencers in WebRTC wanted access to it and were willing to pay, so I made it into a product. Since then it had a few more customers who got exclusive ongoing access to this dataset, and now, I decided to repackage it in a different fashion, making it more accessible to more companies.

What’s in the WebRTC Dataset?

The WebRTC Dataset itself is a collection of vendors and projects who are making use of WebRTC in one way or another. It can be anything from a healthcare service to an outsourcing vendor to a live streaming service or a contact center.

The list includes today around 1,200 vendors and counting – it grows and gets updated on a monthly basis.

You’ll find in the dataset vendors large and small. Anything from Google, Cisco and Facebook to small startups and even individual projects that are popular or interesting enough.

You’ll find there acquisitions made in the industry, with reasons behind them and my own indication of how related they are to WebRTC.

You’ll find there vendors who have shut down. Those who have pivoted and changed their focus.

When the information is publicly known, available or can be found online – the suppliers that are used by a vendor are also indicated.

Here’s an example vendor’s information from the WebRTC Dataset:

The page is split into several parts:

  1. The top part, where general information about the company/project can be found. Including things like size, ranking, status and external sources such as Crunchbase
  2. Then there’s the verbal description and notes, which gets updated through time as the offering evolves
  3. After that, different classifications. These are parameters that you can easily use to filter out or find similarly typed vendors in the dataset
  4. Then come links from other sources as well as my own blog and the latest tweets from that vendor
  5. Last but not least, a quick form in the end allows you to ask anything you have about this vendor and get direct answers from me
Where does this data come from?

All over the web.

Since I am actively working on projects like WebRTC Index and WebRTC Weekly, I got to keep tabs with anything related to WebRTC. I go over the blogs of all the vendors using WebRTC and investigate anything that looks like RTC that I bump into in whatever it is that I am reading. On top of that, I use additional sources like Google Alerts and a few other trade secrets

And I’ve been doing this since 2013.

The data in the WebRTC Dataset got created along the way. First as a resource for me to use whenever I need research information on certain domains. And then because it made sense to package it as a distinct product of its own.

Whatever is on the WebRTC Dataset it is something you can go and find out on your own. But it will take you time. Lots and lots of time.

What can you DO With the WebRTC Dataset?

Lots of things actually. It all depends on what it is you’re trying to gain.

Here are a few ideas and uses that people have been using it for already:

  1. Mark potential companies as leads for your salespeople – if you have a cool solution or service that can fit a certain segment, then you can find some interesting companies who might be interested in what you have to offer in this dataset
  2. Check out your competitors – find who they are. See who their known customers are. Compare them to your own company
  3. Find target markets and their size – need to decide where to put your focus? Should it be Healthcare or should it be Education? Should you offer a click to dial button as a service or go for a video chat widget instead? Who are the competitors in the niche you’re trying to carve for yourself? What are they doing?
  4. Understand market trends – here’s what Serge Lachapelle, who was Group Product Manager at Google heading their WebRTC efforts, had to say of the time he used the WebRTC Dataset:

The dataset enables me to understand where the WebRTC platform is going and make strategic roadmap decisions based on where the innovation and heavy usage lies. Being able to get an updated complete view of the market at any given point in time over a large set of criteria makes it easy to see trends in different industries and verticals that make use of WebRTC.

I am sure you’ll be able to find other ways to use it if you only think about it.

And me?

I use this WebRTC Dataset all the time. One of the things I use it for is my annual “WebRTC State of the Market” infographic.

Here’s the one for 2016 and the one for 2017 that I created.

How about a sneak peak?

If you want to see how the WebRTC Dataset feels like to use, then here’s a short video:

I’m interested. Now what?

Access to the WebRTC Dataset comes at $2,400.

The WebRTC Dataset access gives you 1 month of access to all the vendors there. You’ll be able to download the main worksheet and use it after that month is up.

You can decide to purchase it at any point in time, just head to the WebRTC Dataset page.

While we’re at it – if you decide to purchase before the end of July (even if you plan on using it later on), there’s an early bird discount of $400. Just use coupon code DATASET-EARLYBIRD.

Get the dataset

The post Drilling into the WebRTC Dataset appeared first on

SIMCom SIM7100E LTE modem

TXLAB - Sun, 07/23/2017 - 03:04

SIMCom SIM7100E is a recent LTE modem released by Simcom. It’s approximately $20 cheaper than Huawei LTE modem, and also it provides USB voice function, so it could be integrated with FreeSWITCH mod_gsmopen module (this needs development).

My set of udev rules and chat scripts is updated with SIM7100E information, and here’s a copy:

cat >/etc/udev/rules.d/99-wwan.rules <<'EOT' # SIMCom SIM7100 SUBSYSTEM=="tty", ATTRS{idVendor}=="1e0e", ATTRS{idProduct}=="9001", SYMLINK+="ttyWWAN%E{ID_USB_INTERFACE_NUM}" SUBSYSTEM=="net", ATTRS{idVendor}=="1e0e", ATTRS{idProduct}=="9001", NAME="lte0" EOT cat >/etc/chatscripts/sunrise.SIM7100 <<'EOT' ABORT BUSY ABORT 'NO CARRIER' ABORT ERROR TIMEOUT 10 '' 'AT+CFUN=1' OK 'AT+CMEE=0' OK 'AT+CGDCONT=1,"IP","internet"' OK '\dAT\$QCRMCALL=1,1' OK EOT cat >/etc/chatscripts/gsm_off.SIM7100 <<'EOT' ABORT ERROR TIMEOUT 5 '' 'AT\$QCRMCALL=0,1' OK AT+CFUN=0 OK EOT cat >/etc/network/interfaces.d/lte0 <<'EOT' allow-hotplug lte0 iface lte0 inet dhcp pre-up /usr/sbin/chat -v -f /etc/chatscripts/sunrise.SIM7100 >/dev/ttyWWAN02 </dev/ttyWWAN02 post-down /usr/sbin/chat -v -f /etc/chatscripts/gsm_off.SIM7100 >/dev/ttyWWAN02 </dev/ttyWWAN02 EOT


Filed under: Networking Tagged: 3G, GSM, linux, lte, pcengines

Google and WebRTC. An Interview with Niklas Blum

bloggeek - Thu, 07/20/2017 - 12:00

Where are we headed with WebRTC?

Google made an interesting announcement recently. It was about WebRTC 1.0 and Google’s own commitment to it. It seems we’ve come to a point in time when WebRTC is considered a done deal and the rest are just details – getting bugs fixed and polishing its performance.

I wanted to understand a bit more where we are headed, from the point of view of the company who lead the effort up until now. So I reached out to Niklas Blum, who is leading product management for WebRTC at Google, to answer a few of my questions.


How is it like to manage something like WebRTC at Google?

WebRTC is an exciting project. It is one of these kind of projects that are only possible at companies like Google and a few other places when you think of scale and impact of the technology. We started about 6 years ago as an open source project in Chrome and now WebRTC is providing the stack for an ecosystem for real-time communication services on Web. From a product management perspective there are tons of requirements impacting the platform – ranging from enterprise multi-party communications to p2p video calling on bad networks and even streaming services. It’s a very challenging and exciting time, with so many opportunities to further evolve the product.


What metrics do you use to gauge WebRTC’s success?

We have very practical metrics like number of API requests and amount of media/data being consumed in Chrome from users that opt-in to share this data with us. From a product perspective, I like to measure the impact of the technology on the Internet. You are tracking for example the number of projects and services that build with WebRTC. The latest update I got from you was around 1200 projects and companies. I think this is a great metric reflecting the success of WebRTC and the impact we achieved by open sourcing it.


You recently made an announcement in discuss-webrtc around WebRTC 1.0. Why now?

We have reaching our goal of having all the standards defined, and the technology is now stable enough for everyone to use. The web-based RTC ecosystem is becoming mature as more and more services that build on top of WebRTC are getting massive reach.

With Chrome, Edge, Firefox and Safari supporting WebRTC, about 80% of all installed browsers globally have now WebRTC build in. This is a big milestone for us as we are achieving our initial goal of making audio and video available in all browsers, through a uniform standardized set of APIs. Additionally, formerly application-focused communication services are transitioning towards the Web platform and adopting WebRTC.

About 80% of all installed browsers globally have now WebRTC build in
Click To Tweet

We believe that interoperability between different WebRTC browsers is now of key importance to continue growing the adoption of WebRTC. It’s also of key importance to provide stability and a common ground to services and companies for continue growing a user base and eventually a flourishing business.


6 years in. What would you say worked great with WebRTC and what needs some improvement?

Our original mission to bring secure p2p real-time communication to the web has become real. This by itself is major contribution to the Web platform and the team is incredibly proud of this achievement. Our current efforts can be split into two main categories:

  1. Finalize the specs in Chrome
  2. Provide enterprise-grade reliability

We are working very hard on performance and to iron out remaining reliability issues in Chrome to make WebRTC the solution of choice for enterprise-grade communication services. These efforts address bugs like missing audio-input from the microphone or when the the camera is not detected. We are also getting close to launching a completely new echo canceller in Chrome for desktop. This should significantly improve the call quality when no headset is used on various devices. Additionally, we have major projects aiming at removing glitches in the audio and video capture and rendering processes. We are porting these time and resource critical processes to Mojo, a new process framework in Chrome. This will allow us to have a much better real-time performance in Chrome.


Looking 2 years ahead. What should we expect to see coming to WebRTC? AV1? Support for AR? …

Google is a founding member AOMedia and very active in defining the AV1 bitstream. Once AV1 is finalized we will start work on adding it to WebRTC. AR/VR/Mixed Reality is a completely new technology space with the potential to change how we consume services and media fundamentally. But the platform and overall product/market-fit is still unclear. But adding AR/VR functionality to WebRTC is definitely an interesting idea.

An interesting opportunity for evolving WebRTC is to replace RTP with QUIC. Experimenting with QUIC as media transport protocol could reduce the transport-layer protocol overhead and provide integrated congestion control. We also consider using QUIC for the DataChannel that is being used a lot by p2p CDNs for content distribution. Generally, we believe that there are still quite a few opportunities for reinventing real-time communications.

Looking a bit further ahead, a new mobile network generation (5G) is emerging. Which role WebRTC will play here still needs to be identified. But generally, having more bandwidth and lower latency available will open the door to explore video resolutions >4K and massive parallel connections. Additionally, having new software-defined networking functionality exposed to the application-layer seems to be an interesting option to improve real-time communication services. It will be very interesting to see the opportunities for WebRTC here.


During your time as the product manager of WebRTC at Google. What was the thing that surprised you the most?

I am still surprised every day by the creativity of developers building great services on top of WebRTC and the value those provide to users. A company called Qbtech, for example, uses WebRTC in a product that assess symptoms of ADHD. While traditional methods for assessing ADHD typically use subjective rating scales from physicians, Qbtech provides objective measurements by analyzing motion tracking over video. After implementing WebRTC, they went from specialized hardware to a web application that could run on a normal computer — opening up access to this technology to smaller clinics, schools, and even rural providers that might not have the resources for more specialized solutions.

Of course, there are many other great services that use WebRTC, but it’s this kind of out of the box thinking to apply WebRTC beyond its original audio/video calling use case and the value that is created by it that always surprises me.

How can developers contribute to WebRTC?

We have received thousands of user feedback reports and feature requests in the WebRTC and Chromium trackers from the growing WebRTC developer community. This feedback has been extremely valuable to improve WebRTC overall and especially to make it more stable for production usage. Generally, developers can provide feedback at by filing bugs or feature requests. And if you want to do more – you can become contributors and help us polishing the codebase – either as an individual or a company.


The post Google and WebRTC. An Interview with Niklas Blum appeared first on

FriendlyELEC NanoPi NEO Plus2

TXLAB - Wed, 07/19/2017 - 00:56

NanoPi NEO Plus2 is a brand new board released by FriendlyELEC. It’s slightly bigger than the NEO2 board, and packed with much more cool stuff: 1GB RAM, Wifi+Bluetooth module, and 8GB eMMC chip. It has also two USB2.0 port connected to independent USB controllers.

The NanoPi NEO Plus2 Basic Kit accompanies the board with an acrylic enclosure, and the first orders are delivered with an UART USB adapter. They also listed an antenna, but I did not receive it in my kit. Anyway I have a better option, a flat self-adhesive antenna like this one.

The acrylic enclosure is about two times thicker than that for NEO boards, and it also has a hole for antenna mount. I added 8 pieces of M2.5 washers and 4 M3 pillars to the original design, to make it more long-lasting. The photo below has the UART adapter plugged in.

Armbian still needs some work to be done to support this new board. But the Ubuntu image that is available from FriendlyELEC is quite enough to demonstrate all the hardware capabilities. Unlike Armbian, it does not mount /tmp and /var/log as tmpfs, so the SD card may experience a faster wearing.

Filed under: Hardware Tagged: arm, friendlyelec, linux


Subscribe to OpenTelecom.IT aggregator

Using the greatness of Parallax

Phosfluorescently utilize future-proof scenarios whereas timely leadership skills. Seamlessly administrate maintainable quality vectors whereas proactive mindshare.

Dramatically plagiarize visionary internal or "organic" sources via process-centric. Compellingly exploit worldwide communities for high standards in growth strategies.

Get free trial

Wow, this most certainly is a great a theme.

John Smith
Company name

Yet more available pages

Responsive grid

Donec sed odio dui. Nulla vitae elit libero, a pharetra augue. Nullam id dolor id nibh ultricies vehicula ut id elit. Integer posuere erat a ante venenatis dapibus posuere velit aliquet.

More »


Donec sed odio dui. Nulla vitae elit libero, a pharetra augue. Nullam id dolor id nibh ultricies vehicula ut id elit. Integer posuere erat a ante venenatis dapibus posuere velit aliquet.

More »

Startup Growth Lite is a free theme, contributed to the Drupal Community by More than Themes.