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New Member

FXO Issue


I have a Router 1700 running IOS 12.3(7) is a small office with 3 IP phones connecting those phones to our main Call Manager 6.1, the issue is with the incoming calls from the PSTN, the router has a card VIC2-FXO with 2 lines. When someone call from the PSTN to the office and the call is not answered the router put  both port busy. I made a test making a call from my cell to both lines and i closed the call on my cell but the phone keep ringing like 5 times more. For restablish the lines is necesary to reboot the unit because if we shutdown the ports i got this message "DSPRM-3-ERROR_NO_DSP_RESOURCES: Insufficient DSP resources to run voice channel"

The router has configure this in both voiceports

voice-port 2/0
connection plar 7021
station-id name 8092611375
station-id number 8092611375
voice-port 2/1
connection plar 7021
station-id name 8095868033
station-id number 8095868033

dial-peer voice 1 pots
destination-pattern 9T
port 2/0
dial-peer voice 2 pots
destination-pattern 9T
port 2/1
dial-peer voice 400 voip
destination-pattern 7021
voice-class codec 1
session target ipv4:
incoming called-number .
dtmf-relay h245-signal h245-alphanumeric
no vad

Thanks for your help

New Member

Re: FXO Issue

Normally codec types of analog lines and IP phones are different.

FXO: G.711ulaw/G.711alaw. IP phone: G.729r8/abr8/ar8 etc.

That's why we need DSP to do the transcode jobs.

Just my thought.