I don't think much has changed from the "old days". I know there's a ton of new h.323 features, but those aren't in CVOICE. And most aren't used in simple networks. The VoFR stuff will probably go away.
SIP's the new thing, but not there yet -- RFC 1149 Compliant. ""Priscilla Oppenheimer"" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > Tom Scott wrote: > > > > Having asked about VoMPLS transcoding from analog voice to MPLS > > frames without intermediate IP packets, my lab partner noticed > > that the CVOICE book (edited by Steve McQuerry etal) discusses > > VoFR and VoATM (chapters 8 and 9): > > > > > > analog +-------+ +-------+ analog > > phone A1 ---- | | ATM | | ---- phone B1 > > ... | rtr A | ---- or FR ---- | rtr B | ... > > analog ---- | | cloud | | ---- analog > > phone Ai +-------+ +-------+ phone Bj > > > > > > Are we reading this correctly, that the analog phones plug into > > the cisco routers and the analog voice traffic is transformed > > into FR frames or ATM cells, with no IP packets in between? > > It makes sense to do it that way in some applications. For > > example, if you have a call center in a distant suburb across > > a LATA line or two, that services a metropolitan area, then > > you'd want to bypass long-distance charges if at all possible. > > > > This seems like an easy way to do it. But what handles the > > call control? Does the router do that? Some of the diagrams > > in the CVOICE book have no PBX (or CCM) in them. Does the > > router translate the call-control signaling from the analog > > phone into corresponding pass-through signaling in the ATM/FR > > packets (sort of like user-to-user signaling that could be > > passed through SS7, in this case the users are the routers > > and the network is the ATM/FR switches)? > > Yup, you got it, although it may be even simpler than you imagine. > > Before AVVID, Cisco did VoIP, VoFR, and VoATM, as discussed in the CVOICE > class. With these solutions, you simply connected analog phones to FXS ports > on routers. The routers digitized and compressed the dialed digits and the > voice itself and packetized it. If it was VoATM or VoFR, there was no IP. > The data was simply put into data-link-layer frames (or cells with ATM). > > You asked about the call-control signaling from the analog phone, but how > much would there be? These phones would be your basic $5.99 KMart special > with no bells and whistles, so to speak. The router provides dial tone and > picks up the dialed digits and forwards them to the other router. > > As you can probably tell, I'm not a telepony expert, but I have gotten quite > a few of these simple voice/data networks up and running. It's very easy. > There is no Call Manager! And, as you mentioned, the major benefit is that > you bypass long-distance charges because you simply use the existing data > network. You may need to prioritize voice, and break up big data packets to > get the low level of delay required for voice, but other than that, there's > not much to it. The original CVOICE class covered only these types of > solutions and I'm sure the book still has a lot of this flavor, although > both the book and the newer version of CVOICE also cover newer solutions too > these days probably. > > _______________________________ > > Priscilla Oppenheimer > www.troubleshootingnetworks.com > www.priscilla.com > > > > > -- TT Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=53585&t=53567 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
