passport at heart an ATM switch????????/ Passport is FR.
-Nakul ""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=73061&t=73048 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
