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=73051&t=73048 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
