SIP Calls over MPLS - Packet Sniffer Issue

[ciscovoipsupport]

Topology:

IP Phone => SCCP => CUCM => SIP => CUBE => Service provider

Issue:

I tried to collect packet trace from both port of CUBE to troubleshoot and identify choppy audio. Unfortunately the packets received and sent are over MPLS due to which i am not even able to see RTP Stream (not even SIP signalling). Calls are sucessfull with G729 Codecs.

How can i decode and play G729 codec over MPLS network. My network team also use to say VRF. not sure if VRF network and MPLS network are the same.

Cisco Forum Document i reffered was https://supportforums.cisco.com/document/29616/utilizing-new-packet-capture-feature

It says we cannot use it for MPLS network. Are there any alternatives..

Please help..

[ryanticer]

Hello,

I would recommend installing a temporary switch in place between the CUBE and the upstream provider, which would then allow a monitor session (SPAN) port to be setup to capture the traffic on a laptop or nearby PC using wireshark.

From there, the G729 audio can be analyzed for lost packets, jitter, etc.

Thanks!

Ryan

[ciscovoipsupport]

not an option..

[m.batts]

I think you can save yourself a lot of time , by first asking or checking how QOS is configured on the MPLS as it sounds to me quite obvious that QOS is not functioning correctly.

[ciscovoipsupport]

I am aware of this option.. but QOS is not managed by my team.. whcih is why i wanted to prove to that team that the packets received from your network has choppy audio...

Please advise how to collect RTP Stream(G729) on MPLS cloud... so that i can playback the audio and make them listen the RTP Stream...

[ryanticer]

Hello,

As an alternative option, you could do a packet capture before it hits the CUBE, assuming the CUBE isn't causing the choppy audio, to see if you're seeing the issue there.

Thanks!

Ryan

[ciscovoipsupport]

Preciously what my question is.. I am not able to decode RTP audio Stream over MPLS network..

How do i collect RTP Stream which has MPLS frame ?

[ryanticer]

Hello,

What model and IOS version is the CUBE?

Thanks!

Ryan

[ciscovoipsupport]

Cisco IOS Software, C2900 Software (C2900-UNIVERSALK9-M)

Version 15.2(4)M5

is the method to collect RTP packets on MPLS and VRF network the same?

Can they be decoded the same way?