Welcome to Unified Networking

Cisco CME DSP Issue If you are running through any of the following error, then this post is for you.  Applicable to Fxo, Fxs ports and PRI E1/T1 ports deployments. 1. Only one way communication is happening 2. Frequently getting the console message:  FLEXDSPRM-3-TDM_CONNECT: failed to connect voice-port (1/1/0) to dsp_channel(1/1/3) 3. Able to call but no audio The reason here, we can call it as a cisco bug or misbehaviour of the router. When there are frequent changes at one side of the PRI trunk or fxs port then router's dsp fails to function properly. Signalling works without any issues though. When this happens you might face one way audio through router. That means if you are having a pri trunk then calls in one direction, pbx --> router or router --> pbx works but not works in the reverse path. Even though if you are calls are working in both the ways, if you see this error, you might experience calls disconnecting in feature. So you should be aware.

Hello all,            In this, document i will tell you how to successfully integrate Cisco Call manager Express (CME) with any third party PBX with examples. This process is called PRI Trunking or PRI integration.           Recently i was into PRI integration with 3 Cisco routers (Cisco 3945, 2951 and 4130) with IRIS lite PBX.           Integrating a PBX is not a that hard as we think, but it's bit sensitive. Sensitive in the sense while during the PRI integration we just need to be careful while assigning the parameters, they should match at both ends, i.e., on PBX side and CME side as well.           The very first thing to consider for PRI trunking is   "cable".   Yes, the cable which needs to connected between PBX and CME should be a cross over cable. For connecting a cross over cable, at cisco side we should connect to 1,2 4,5. In PBX side we need to check the cross connects and connect them accordingly.  ( To be frank i am not sure on cabl