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VG248 and Modem Issues

I have verified that my MGCP setup matches the setting outlined by Dave. The one thing I did not check earlier was the "Passthrough Signalling" setting. It was set to "legacy". Upon changing this things got even worse. I was just curious as to why. Here is my setup:

- 4604AGM - 2 PRI's

- ECAN Disabled on VG248 Modem ports

- Fax Relay disabled on all VG248 ports

- The commands below are configured on the gateway

- no ccm-manager fax protocol cisco

- mgcp modem passthrough voip mode nse

Speed/Duplex Hard Coded on each side (switch interface is clean)

- QOS is properly configured everywhere on the network according to AVVID guidelines

- ERL Levels are at an acceptable level on the gateways

- Layer 1 issues have been checked out.

- Version 1.2.1 on VG 248

- Version 12.2(15)T8 on AGM

- Show controllers T1 on the PRI's shows no linecode violations or slips

- ccm-manager config portion

ccm-manager redundant-host x.x.x.x

ccm-manager mgcp

no ccm-manager fax protocol cisco

ccm-manager music-on-hold

ccm-manager config server x.x.x.x

ccm-manager config

- mgcp configuration


mgcp call-agent x.x.x.x 2427 service-type mgcp version 0.1

mgcp dtmf-relay voip codec all mode out-of-band

mgcp rtp unreachable timeout 1000 action notify

</b>mgcp modem passthrough voip mode nse</b>

mgcp modem passthrough voip codec g711alaw

mgcp package-capability rtp-package

no mgcp package-capability res-package

mgcp package-capability sst-package

no mgcp timer receive-rtcp

mgcp sdp simple

mgcp fax t38 inhibit

mgcp bind control source-interface Loopback0

mgcp bind media source-interface Loopback0

mgcp rtp payload-type g726r16 static

<font color="red"><Cut From Dave Goodwin Post></font>

4. IOS for 17xx/26xx/36xx/36xx = 12.2(15)T8. To configure fax and modem passthrough for H.323, use:

voice service voip

fax protocol pass-through g711ulaw

modem passthrough nse codec g711ulaw

To configure fax and modem passthrough for MGCP, use:

no ccm-manager fax protocol cisco

mgcp modem passthrough voip mode nse

5. VG248 software = 1.2(1). To configure fax passthrough, set the Telephony Port Specific Parameters for each desired port for Fax Relay (disabled). Also set the Telephony Advanced Settings for Passthrough signaling to (IOS mode).

New Member

Re: VG248 and Modem Issues

Based on the information you have given, I think you will need to open a Cisco TAC case. The engineers at the Technical Assistance Center will be able to help you with this.