The main thing is that *proxies* don't have this behavior!
I consider B2BUA to be a very generic term - it can do most anything.
While SBC is, as Hadriel says, a marketing term, its more specific than
B2BUA and most things called that have, or can be configured to have,
this behavior.
Thanks,
Paul
On 7/18/13 11:22 AM, Joel Gerber wrote:
> SBC is a rather arbitrary term referring to a bunch of different functions.
> Typically an SBC is a B2BUA, RTP media-proxy, stateful firewall, QoS/policer,
> NAT traverser and a transcoder, but this is not always the case. Some vendors
> stick on the name SBC, and it just performs SIP ALG functionality.
>
> I typically just call them B2BUAs, and will specify whether they have
> additional functionality, because the term SBC really doesn't mean anything
> when there is no standard as to what functionality a device needs to support
> in order to earn the name.
>
> SBCs typically follow a bunch of separate standards, without implementing any
> "magic" outside of what a certain standard allows. IE: In RFC 3261, there is
> no mandate on what a B2BUA has to do when it translates signals from a dialog
> facing one endpoint to a dialog facing another. Removing/Adding/Changing
> header values is both allowed, and maybe even expected.
>
> Joel Gerber
> Network Specialist
> Network Operations
> Eastlink
> E: joel.ger...@corp.eastlink.ca T: 519.786.1241
>
> -----Original Message-----
> From: Paul Kyzivat [mailto:pkyzi...@alum.mit.edu]
> Sent: July-18-13 11:11 AM
> To: ikuzar RABE
> Cc: sip-implementors@lists.cs.columbia.edu
> Subject: Re: [Sip-implementors] RTP flow's route follows SIP flow's route ...
>
> Then stop calling it a *proxy*!
> It is an SBC.
>
> Thanks,
> Paul
>
> On 7/18/13 6:28 AM, ikuzar RABE wrote:
>> Ok thanks for your responses,
>> There is indeed an RTP proxy within the sip proxy... and it works as
>> you described above.
>>
>>
>> 2013/7/17 Paul Kyzivat <pkyzi...@alum.mit.edu
>> <mailto:pkyzi...@alum.mit.edu>>
>>
>> As others have noted, for this to happen the "proxy" (proxies?) needs to
>> modify the SDP to cause this to happen. If it does this it has violated
>> the rules for a proxy. Devices that do this are typically called Session
>> Border Controllers. It is very common. There are both advantages and
>> disadvantages to doing this.
>>
>> Thanks,
>> Paul
>>
>> On 7/17/13 5:29 AM, ikuzar RABE wrote:
>> > Hi all,
>> >
>> > I saw a RTP flow which is not directly established between UAC
>> and UAS but
>> > goes through a SIP proxy ...
>> >
>> > Is there any information in SIP message exchange producing this
>> situation ?
>> >
>> > Thanks for your help,
>> >
>> > ikuzar
>> > _______________________________________________
>> > Sip-implementors mailing list
>> > Sip-implementors@lists.cs.columbia.edu
>> <mailto:Sip-implementors@lists.cs.columbia.edu>
>> > https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
>> >
>>
>> _______________________________________________
>> Sip-implementors mailing list
>> Sip-implementors@lists.cs.columbia.edu
>> <mailto:Sip-implementors@lists.cs.columbia.edu>
>> https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
>>
>>
>
> _______________________________________________
> Sip-implementors mailing list
> Sip-implementors@lists.cs.columbia.edu
> https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
>
_______________________________________________
Sip-implementors mailing list
Sip-implementors@lists.cs.columbia.edu
https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
