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reg:2821 fxo&fxs

Dear sir,

one of my customer is having 2621xm router and 2821 router in this 2621xm we have FXS module and 2821 we have fxo 2port customer requirement is he was having icomm epabx i configurd both the routers and iam able to ring that fxs phone but my voice is not clear and iam getting high noice but iam able to ring that subscriber iam attaching the my tech support report plz go through that and suggest me the best config and ios also.Shell i connect back to back using ethernet .shell i test voice like in back to back set up.plz help in this





Re: reg:2821 fxo&fxs

When a router does not recognize a voice port, it may be because the router is not loaded with the proper Cisco IOS image required for voice support. For a Cisco 1750 router, ensure that it does not have PVDM-256K-4 and PVDM-256K-8 DSPs. These are packet voice/data modules (PVDMs) for Cisco routers 1751 and later. If the Cisco 1750 router does not have the correct PVDM, the voice ports may appear in show version and show diag command output; however, there is no dial tone. Also, no DSPs are seen in the show voice dsp command output. The Cisco 1750 router should carry the proper PVDM-4 and PVDM-8 DSP cards

Re: reg:2821 fxo&fxs


As pradeep mentioned you need to have different feature set of ios code to have the support of fxs or fxo cards in your router...

Earlier with Cisco 1750 it was called as IP and IP PLUS...normally boxes comes with IP and for voice cards u need to have ip plus feature set...

You can use the below link to find out the exact ios code to be installed in your router to have the support for the voice cards..