Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. And see here for current known issues.

New Member

RTP & IP precedence

We're running a 3745 as a gateway with an E1 into the PSTN. The 3745 connects to a 3750 in router -switch mode, via a FDX 100Mbps connection. The 3750 connects to seven 3550 switches via MM SX interfaces running FDX, all 3550's have in-line power UTP connections.

When we monitor [using NetMon]the IPT traffic to and from an IP phone the RTP-IP precedence is Critical/Exp outbound and Routine inbound.

When we monitor the IPT traffic to and from the gateway we see that the traffic from the IP phone now has an RTP-IP precedence of Routine, whereas the traffic from the gateway has an RTP-IP precedence of Critical/Exp.

Is this to be expected?

If so, can it be changed to have a RTP-IP pecedence of Critical throughout the path from gateway to IP phone?

New Member

Re: RTP & IP precedence

This will all depend on how QOS has been configured on your switches. How the Trunks are setup etc. I suggest you ensure that all LAN ports are set to QOS Trust COS and trunks setup to prioritise them

New Member

Re: RTP & IP precedence

Thanks for the response.

I answer to your query; the LAN ports are setup to "QoS Trust Cos" and the trunks are setup to prioritise appropriately. However we are concerned that there may be issues between the two layer 3 devices, 3750 & 3745, under high load as there is no L2 trunking only, CEF.

CreatePlease login to create content