""nrf"" wrote in message.. > ISIS has more tuning parameters and more extensibility than OSPF. > It also has significantly more scalability than OSPF. I dislike > EIGRP precisely because it's inner-workings are closed.
If Cisco opened up EIGRP and you understood it completely, would you be more likely to use it? Personally, I think EIGRP's concepts are excellent and even though it has a bit of feature-creepism, the advanced algorithms and workings make it very interesting and useful. To be honest, I really prefer overabundant IBGP networks. Carrying routes in IGP's seems rather archaic and silly. BGP is very stable to hundreds of thousands of routes, and IGP's won't ever scale that high (at least I hope not). Code-wise, you can easily compare them: BGP is the most powerful routing protocol and is only ~40k lines of code, ISIS is smallest with ~25k lines, EIGRP next with ~35k lines of code, and OSPF is over 100k lines. Since BGP is almost always needed, especially in this day-and-age, let IGP carry only next-hop routes for BGP (infrastructure) and let that protocol be the simplest needed to do the job. ISIS fits that bill very well, IMO. OSPF is the Microsoft of routing protocols (oh yeah... it was *built* and is *pushed* by Microsoft, strange how that works, huh?). EIGRP is very elegant, and an excellent compromise between ISIS and OSPF - and until recently (12.1 IOS), I would not have said so considering the early problems with EIGRP SIA's. > I am convinced that MPLS will indeed become the next big thing > in SP's, but not the flavor of MPLS the way it is constructed > now. In particular, I see RFC2547 and MPLS-TE as being only > minor considerations in the future for MPLS implementation > (granted, they are the major reasons now). Instead, I think that > MPLS will ultimately morph into a generalized technology by which > providers will be able to offer a complete range of services and > features using a unified (dare I say 'converged'?) network. In > particular, the day that MPLS can offer a complete range of > ATM/FR/voice services without forcing a wholesale migration to > IP from legacy gear is the day that widespread MPLS migration > will occur. Anticipation of this has already occurred - providers > are now unwilling to invest in legacy ATM gear because they are > hoping that MPLS will be fully baked in the next few years. MPLS > will also, through its GMPLS offshoot, be able to offer important > network management advantages. MPLS is probably over 1 million lines of code today, and it's not even fully mature. I don't see the benefit due to the complexity. It's not simple; it's not robust. What problems did ATM solve anyways? Traffic Engineering? Today's solution: Packet Design, Caimis/IXIA, etc. Quality, constraint-based routing, and classes of service? Nobody wants classes of service, they all want "the best" service. Constraints are good, but they are useless to anyone who doesn't have 2 Ph.D's and 15-20 years of operator experience. There are only so many people in the world with such qualifications, not every network can afford to hire them. I see your points, but I think you need to expand on them and clarify what you think MPLS/GMPLS will do. Providing legacy support is not a very valid reason. Network management could be considered a good reason, but I haven't seen MPLS help with this yet, only make things more complex (have you seen Eureka/VPNSC?). > Therefore, sorry to say it, but I see things like RFC2547 and > MPLS-TE as only sideshows to the 'real' MPLS initiatives - ATM > interworking, circuit-emulation style technologies like the > Fischer draft, GMPLS, and the like. RFC2547, in particular, > I see as a quite dangerous sideshow because of its implication > to BGP scalability and stability. MPLS will always be a hack and a sideshow. Why else would people be so religious about it? I am neutral on MPLS, just like I was with ATM. It can provide some benefit in the short-term to solve a variety of operator network problems. It is not built for the long-term in mind. "Solving everything" is too lofty a goal for any would-be technology. > That's a nice summation of where technology is going. But I > would add that you shouldn't fixate yourself on the Internet. Too late. I'm already fixated. ;> Part of me hopes that you are right about private networks taking over, but the other part of me hopes we don't repeat the same mistakes in the past (X.25 and ATM all over again?). Yes, these were mistakes. Tell me how many times you had conversations like this over X.25 private networks (or ATM private networks)? Then tell me how many you've had over the Internet? The Internet is the most powerful network we've seen yet. It's not going to go away tomorrow, and it's not going to degrade into something unusable. It's going to evolve. -dre Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=58585&t=58493 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
