Call Flow for internal calls

[willsupport]

Hi all,

i would like to know the call flow of the calls between two internal DN.

I have some problems of one way voice between DNs and i need to know what i can check to solve the problem.

Thanks,

Alessandro

[Jaime Valencia]

Signaling and call control goes to CUCM, media flows directly between endpoints unless you chose to use an MTP/TRP in the media flow.

[willsupport]

Thanks for the reply, can you explain what are:
- signaling
- call control
- media flow

Thanks,
Alessandro

[Jaime Valencia]

Signaling and call control are the same, messages that are interchanged between the device and CUCM to send/receive what it takes to make a device work

https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cata/186_188/2_15_ms/english/administration/guide/sccp/sccp/sccpaaph.pdf

media is the RTP, which is the actual voice/video

[willsupport]

So, my problem is related to the media flow.
What type of troubleshoot should i do?

I saw in the flow statistics of the phone if there are any packet drops but the counter is 0

[Jaime Valencia]

One way/no way audio/video is most usually related to routing.

[willsupport]

So you think that there could be a problem related to the reachability of the phone each others?

[anshu1987]

Hi Jamie, 

if TRP is enabled is there a possibility to allow devices in same location to do direct RTP?

Thank You 

Anshu