At 2:22 PM +0000 7/26/03, Nakul Malik wrote: >passport at heart an ATM switch????????/ > >Passport is FR. > >-Nakul
The Passport is internally a cell switch, onto which Nortel has overlaid a great many other features. Before I went to work for Nortel, I consulted on the BGP implementation, and later worked as a router designer in the corporate R&D lab -- often hearing "oh, we can make the Passport do that too." > > > >""annlee"" wrote in message >news:[EMAIL PROTECTED] > > John Neiberger wrote: >> >> > I'm just now digging deeper into current VPN technologies since I'm >> > researching Qwest's PRN service. I'm awaiting a definitive answer from >them >> > but it appears that their PRN service is 2764-based, which apparently >means >> > it does not use MPLS like 2547-based VPNs. I'm curious about the >> > implications of choosing one model over the other. >> > >> > I thought the market trend was toward MPLS-based VPNs but 2764 seems to >> > argue against that. What are the implications of choosing one model over >> the >> > other? Are there any major drawbacks to either one that the other >> > addresses? >> > >> > I'm also a little concerned about vendor choices. Nortel seems to be >> pushing >> > 2764, while Cisco and possibly Juniper are pushing 2547 and MPLS. Is >that >> > correct? If so, is that really that important to the customer? >> > >> > Forgive me if these questions seem pretty vague. I'm still learning >about >> > the technologies involved and I'm not very familiar with the specifics >and >> > the terminology. >> > >> > I'll put in a plug here for Howard's book _Building Service Provider >> > Networks_. Among a number of things it discusses some of these VPN >> > technologies and has been very helpful the last couple of days during my >> > research. >> > >> > John >> Also worth looking at is the hardware component: what will run on >> the hardware you've already got (if anything)? IF you already >> have most or all of the hardware pieces to implement Cisco's >> version, then Cisco's probably makes sense. IF you already have >> the requisite Nortel gear (Passports?), you're probably only >> looking at upgrading to a new PCR (software version). >> >> And there's the training and management aspect -- which suite do >> you know better? Where is the rest of your network going--will >> money spent learning Passport command line be transferable to >> other devices, offering a savings there? My guess is no, but it >> could be possible. Finally, what's the underlying architecture -- >> Passport at its heart is an ATM switch, and Nortel's VPNs using >> virtual routers still looks an awful lot like IP over ATM, with >> all the overhead in play there. If it's Passport they're pitching >> at you, have a good look at the layer 2 technology on switch >> egress. What I saw was: >> >> [data+(local IP hdr)+(carrier IP hdr)+layer2 formatting] >> >> as it went through the cloud. Potentially, that's a lot of >> overhead. If that's not a problem, fine. >> >> Annlee Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=73066&t=73048 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
