Any Opensource SBC

Hi,

Anybody can tell me about open source SBC (SESSION BORDER CONTROLLER)? Thank you

Please do a search before posting - there are some detailed resources here on the forum that go back several years. For example this one ...

http://www.voipuser.org/forum_topic_10099.html

A Google Search for 'open sbc' will give you a reading list that will certainly feature the name 'Borderware' - not an OS application but a very worthy contender.

You can find a further useful list of general OS VOIP Applications here ...

http://www.voip-info.org/wiki-Open+Source+VOIP+Software

When I last looked there was no convincing public project to create an open source SBC, although you could imagine building something using existing open source components, for example Freeswitch, using a B2BUA function. There is no general agreement about the definition of an SBC, so the first step in creating an open source SBC would be to define exactly what kind of thing it is you want to build. Some say that the SBC is like a "voice firewall", where others emphasize edge functions that would make a SIP network look like a conventional telco network, for example having CDRs and lawful intercept capability. Actually even the term SBC is being downplayed by commercial vendors that have these products today. Everyone seems to have their own special name for the "edge box".

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There is no general agreement about the definition of an SBC, so the first step in creating an open source SBC would be to define exactly what kind of thing it is you want to build.

As Martyn says the lack of definition of what an SBC is does create a bit of a problem. Generally the term "SBC" has been used to refer to anything that sits on the edge of a VoIP network, in some manner protecting the core network or assisting it.

I think you can break it down into the following high-level requirements/features:-

Signalling Border Control

Some kind of signalling layer firewall and security. This can be a topology hiding system (so no-one can see what's happening in the core or what it is and how it works) coupled perhaps to an anti-DDOS system. The basic idea is to protect the core. If the core is, say, openSER, then the objective is to ensure that (a) no-one can tell it's openSER and (b) the only traffic that gets through to it is in some way pre-authenticated.

Media Border Control

This will generally take the form of some kind of media (RTP) proxy. It assists in NAT traversal and also this is where you're likely to put in your timers for timing calls if you're running the business with a per-minute/second charging model. It'll probably also have some kind of anti-DDOS system in place. It needs to talk to other things (the CDR and billing controller) and an Enterprise Service Bus type topology is one way of performing that communication. You need to think carefully about how real-time that needs to be - pre-pay and post-pay models have different requirements in this respect. Pre-pay needs to know how long a call at the current rate can last. Post-pay just needs to know how long it was when its finished.

Lawful Intercept

Usually part of the Media Border Controller. It's quite easy to implement - just a case of taking a copy of audio packets flying through the proxy and having the ability to stream that copy elsewhere. The tricky part is matching up which media stream belongs to which conversation. Most media proxies don't care and do not need to know. The police/intelligence services do, of course, need to know - you're likely to get a request in the form of "we want to tap all calls between these two people". Most media servers won't know which streams that refers to, so you need to build something that maintains state of that.

As Gray says, the Borderware devices do all this for you and are reasonably priced (about £3k last time I looked).

One consideration if you're proxying media is whether or not you require more than one, spread about in different continents. Think about the media path - if you have two customers in Australia talking to each other you don't really want to proxy all the audio via London.

As Martyn says, Freeswitch has pretty much all the toolkit you'd need to do any of the above. In terms of signalling border control, openSER/Kamailio also have.

And generally you can find half a dozen open-source SIP and RTP stacks which you could utilise in building what you need.

Thank you for your Post
I want to get opensource SBC for Voip Network. Dean i have read your article how to establish Voip network.http://www.voipuser.org/forum_topic_8289.html
I have got 2 Main things for Voip OpensourceSER and SBC for Cloud Edge . Plzz guide me how can i get SBC for Establishing Voip NETWORK?

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Plzz guide me how can i get SBC

Can't really say much to that without understanding your exact requirements, but you can basically just buy a Ditech or a Borderware device. That's the easiest thing to do.

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get SBC for Establishing Voip NETWORK

Bear in mind an SBC is not a strict requirement - you can run a network without one. If NAT traversal is an issue you can use a media server (like RTPProxy which is open-source). It will leave you slightly open on security, and won't give you lawful intercept. On the latter, you need to ascertain whether or not that's required in your Country.

If you're going with a per-minute model, you'll need to time calls at the edge somewhere. Some custom coding in RTPProxy or FreeSwitch may enable that. Or you could try and create an all-you-can-eat type monthly fee package which avoids the requirement for real-time call detail records.