Live Communications Server and Asterisk


#1

Hi everybody.

I would like to interconnect LCS Server with Asterisk. So, i saw that LCS uses TCP ports while Asterisk uses UDP ports.
Is it right ?

So, i found 2 solutions. The first, using SER, but I don’t know at all how it works. The second is a patch for Asterisk. It allows accept TCP connections on the server (http://bugs.digium.com/view.php?id=4903&nbn=4). But I think it’s not very stable.

Someone has already used one of these solutions ??


#2

I am not sure how the TCP patch enables integration with LCS, as this patch would allow the RTP stream over TCP as opposed to UDP, based on my understanding of the patch. For the SIP interface messaging itself, both use TCP.

What exactly are you trying to acheive with LCS integration?


#3

In first case, I only want to do a trunk between LCS and Asterisk. Some phones will register on LCS and others on Asterisk.

I searched on Google but i didn’t find any help to do that.


#4

[quote=“aurelius”]In first case, I only want to do a trunk between LCS and Asterisk. Some phones will register on LCS and others on Asterisk.

I searched on Google but i didn’t find any help to do that.[/quote]

My understanding of LCS is that it is a SIP proxy that would allow you to use it for connecting two SIP endpoints. So, this could be Asterisk and a SIP compliant softphone, and since they would reinvite the RTP stream is direct between the clients anyway. Have you tried it?


#5

I haven’t tried but I will. Otherwise, are you sure that Asterisk uses TCP, and not UDP, for SIP interface messaging ?


#6

I have only TCP opened on my firewall for the SIP listening ports on my ATAs while I have UDP opened for the RTP ports. Seems to work fine, but then again Asterisk does purport to only support UDP. As on the server Asterisk is indeed only listening on UDP.

Also, what leads you to believe that LCS does not support UDP anyway? I believe it most likely does (although do not know firsthand):

microsoft.com/technet/prodte … .mspx#EIAA

Although, this referes to the RTC and not directly to LCS. Maybe you could shed some light on the relationship here.


#7

LCS does not support UDP for SIP Signaling (only TCP/TLS) and therefore is not SIP complient.

Asterisk currently only supports SIP Signaling over UDP and therefore is also not SIP complient.

But neither claim to be. :slight_smile:

My advice is to use a stateful proxy like ser for inter-application communication. Support is coming for both apps.


#8

[quote=“freevoip4all”]LCS does not support UDP for SIP Signaling (only TCP/TLS) and therefore is not SIP complient.

Asterisk currently only supports SIP Signaling over UDP and therefore is also not SIP complient.

But neither claim to be. :smile:

My advice is to use a stateful proxy like ser for inter-application communication. Support is coming for both apps.[/quote]

Do you recommend SER (openser.org)? Also, I expect Asterisk to get there before ACS… :wink:


#9

I did not realize there was an active SER branch (OpenSER). This is great news as the iptel.org implementation has been stagnant for a while. Thanks for the information.

Use t_relay_to_udp and t_relay_to_tcp to create a stateful proxy for Asterisk->LCS using the iptel.org implementation.

Unsure how this is accomplished with the OpenSER implementation.