how does CallManager Express (CME) work?

rsheladia · ‎08-03-2004

Hello,

Does anyone know how CME works with loca calls? My understanding was that CME uses Skinny to talk to CME and RTP was the call is set up. When I perform the commands show sccp connections and show voip rtp connections detail it shows that no sccp and rtp connections are active. Any clue?

On the other end when I run CME remotely between 2 separate call managers across a WAN. I get a RTP connection, an H323 connection, but no SCCP...any clue on this.

thanks for the help.

patsbc · ‎08-04-2004

I haven't had my morning coffee, so my ramblings may not make sense. But I'll have at it.

For internal (on-net) calls, once CME call control has identified and connected the calling and called endpoints, RTP and state information is exchanged between IP telephone endpoints. Voice traffic does not traverse CCME, as CCME just sets up the call and gets out of the way.

For external (off-net) calls, any IOS supported voice endpoint can be used to connect a call off a gateway. It may go H.323 or SIP to another gateway, to head to another site or the PSTN. The CME router would then maintain the call control as it is converted.

Hope this helps.

Pat