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New Member

Dial-up over VOIP

Good day

I’d like to clarify why I can’t access my email and browse to the net using dial-up over VOIP configuration.

Listed below are the problems I’ve encountered during the testing:

From remote site I tried to dial-out to the internet using VOIP connection, I did able to access my account and successfully connected to the ISP server, but when I browse to the internet, it doesn’t work, I can’t access to the net as well as my email

Network setup

a. My VOIP setup is that I have 2651 router with 4 fxo port at the main office, connected to telco line,

b. remote site has 2651 router with FXS card connected to PBX unit.

Hope you can help me.


Arnold A. Madulin, CCNA,CCDA

Technical Engineer

Powertech Specialist, Inc.

Tel. +632 2990763

Mobile: +63917 7025633

New Member

Re: Dial-up over VOIP

I struggled a long time with modem passthrough on a 4224 with an HDA card with 8 FXS ports. The other end is a 6608. I finally figured out what the problem was. I had the ip precedence for rtp packets set incorrectly. I soon as I changed this setting things took off. I don't know if this is related to your problem but I figured I'd post it.

This is my mgcp config that works great:


mgcp call-agent service-type mgcp version 0.1

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

mgcp modem passthrough voip mode cisco

mgcp modem passthrough voip redundancy

mgcp ip-tos rtp precedence 3

mgcp ip-tos high-throughput

mgcp package-capability rtp-package

no mgcp timer receive-rtcp

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