Good day all.
Please i need to know how many fxo cards can the 2821 cisco router support. The router has two HWIC cards that can support 2 4-voice port FXS/FXOs and an extension module (EM-HDA-8FXS) that specifically supports 8-fxs voice connections. Is there module that can handle FXOs? or can the same card handle both FXS and FXO connections? I hope i'm making sense here.
You can use the NM-HD-2V in any type of NM slot. The PVDM2-16 is a DSP module installed on said NM.
Note that when router is FXO and PBX is FXS, most likely you won't be able to do single stage dialing from PBX extensions to destinations reached via the router. Meaning you will have to wait for router dialtone, then dial the actual destination. This is called two-stage dialing and is quite inconvenient.
So, if you cannot use ISDN BRI or PRI, the only workaround to the above, is to use a mix of FXS and FXO ports. Router and PBX will use their respective FXO port for outgoing calls, FXS for incoming.
This allows for single-stage dialing in both directions.
Thanks for the nice rating and good luck!