>It's probably insufficient to refer to the "source" of igrp without >referring to the "source" for allegedly open standards terminology used to >misdescribe routing protocols such as "distance vector" (hint: NOT cisco . . >.). Then again, when referring to the "source" for IGRP, depending upon the >aspect of the technology you are referring to, better choices to depict as >the "source" of IGRP might include JJ Garcia-Luna-Aceves, Chuck Hedrick or >Len Bosack.
I don't think JJ ever worked for Cisco. He developed the DUAL algorithm at Stanford Research Institute, which licensed it to Cisco. JJ is now at USC. He has said publicly that he had nothing to do with the EIGRP implementation and his current research has produced better algorithms. Bellman-Ford, like Dijkstra, originated from mathematical research not strictly related to routing. Base Algorithm Protocol -------------- -------- Bellman-Ford RIP, IGRP, RTMP, Novell RIP DUAL EIGRP Dijkstra ISIS, OSPF, Novell NLSP, PNNI Path vector BGP > >From Hedrick's report: > >This paper really should show Len Bosack of cisco Systems as co-author, and >possibly should also list an > >unidentified lawyer at Townsend and Townsend. Most of the ideas behind IGRP >are Len's. > >Anyway, none of them work for Cisco (and at least one was kicked out with >extreme prejudice). > >While Cisco has a lot of say over what IGRP is and is not, they have no >authority to say what entities are or are not in the set of all objects >defined as "distance vector routing protocols," precisely because they DO >sell routing products. > >Granting them that authority is almost as inimical to a better understanding >of the subject matter as letting them define the structure & content of OSI >layers. > >----- Original Message ----- >From: "Rick" >To: >Sent: Monday, May 13, 2002 6:42 PM >Subject: Re: Is IGRP actually supported by other vendors? [7:43994] > > >> Priscilla, >> I hate to differ with you on this Hybrid or not but the source says >> it is considered a Hybrid routing Protocol. check the link for yourself >> http://www.cisco.com/univercd/cc/td/doc/cisintwk/ito_doc/en_igrp.htm >> >> I myself am not a fan Lammle, but on this one he is right and you are >wrong >> and YES I said you are wrong! EIGRP is as much Link-State as it is >Distance >> Vector. >> Rick >> >> ""Priscilla Oppenheimer"" wrote in message >> [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... >> > At 04:13 PM 5/13/02, Mike Mandulak wrote: >> > >Lammle refers to EIGRP as being a Hybrid of distance-vector and link >> state. >> > >> > That's wrong. EIGRP is not link-state in any way. EIGRP calculates a >flat >> > routing table that lists networks, distance, and next hop (distance >> > vectors). If the list contains multiple entries for a destination >(because >> > there are multiple ways to reach the destination), the entries are >sorted >> > by metric and the one with the lowest metric is selected. This is very >> > different than how a link-state protocol functions. >> > >> > A link-state routing protocol creates a mathematical graph that depicts >> the >> > network. A link-state protocol implements a sophisticated process, >called >> > the Dijkstra algorithm, to determine the shortest path to all points in >> the >> > graph when the nodes and links in the graph are known. Link-state has a >> > specific meaning to computer scientists. You'll find a lot of good stuff >> > about it if you search with Google. A lot of it is not related to >routing >> > protocols. >> > >> > EIGRP does have some features that make it different from other >> > distance-vector protocols. Although EIGRP still sends vectors with >> distance >> > information, the updates are non-periodic, partial, and bounded. >> > Non-periodic means that updates are sent only when a metric changes >rather >> > than at regular intervals. Partial means that updates include only >routes >> > that have changed, not every entry in the routing table. Bounded means > > that >> > updates are sent only to affected routers. These behaviors mean that >EIGRP >> > uses very little bandwidth. >> > >> > EIGRP also determines a feasible successor, which other distance-vector >> > protocols don't do. Its complex metric is also a feature not found in >many >> > other distance-vector algorithms, (except IGRP of course). >> > >> > Please do not send messages to me directly, especially not to quote >Lammle > > > CCNA fluff. >> > >> > Priscilla >> > >> > >He only gives a brief mention of EIGRP and says to refer to the CCNP >> study >> > >guide for more info. >> > > >> > >----- Original Message ----- >> > >From: "Priscilla Oppenheimer" >> > >To: >> > >Sent: Monday, May 13, 2002 3:19 PM >> > >Subject: Re: Is IGRP actually supported by other vendors? [7:43994] >> > > >> > > >> > > > At 02:44 PM 5/13/02, Mike Mandulak wrote: >> > > > >Lamme's CCNA study guide states that the courde and exam only >covers >> > > > >distance-vector routing protocols (RIP and IGRP). >> > > > >> > > > If it only covers distance-vector, then it could cover EIGRP also. >> EIGRP >> > >is >> > > > also distance-vector. I don't think the test does cover it, but it's >> not >> > > > because the test only covers distance-vector. It's probably because >of >> > all >> > > > the extra features in EIGRP, such as the diffusing update algorithm >> > >(DUAL), >> > > > with the feasible successors and all that other BS. Come to think of >> it, >> > > > maybe I'm glad I don't have to cover it! ;-) >> > > > >> > > > >> > > > >----- Original Message ----- >> > > > >From: "Priscilla Oppenheimer" >> > > > >To: >> > > > >Sent: Monday, May 13, 2002 1:27 PM >> > > > >Subject: Re: Is IGRP actually supported by other vendors? [7:43994] >> > > > > >> > > > > >> > > > > > Well, it occurs to me that IGRP would be easy to implement even >> > >without >> > > > > > Cisco's permission. ;-) It's a simple protocol, for one thing. >> Also, >> > >the >> > > > > > Rutgers paper that describes IGRP has been out for years. Cisco >> never >> > > > > > objected to it. >> > > > > > >> > > > > > EIGRP would not be easy to implement without Cisco's blessings, >> > >developer >> > > > > > support, licensed code, etc. We have probably all tried to >figure >> out >> > > > some >> > > > > > detail of EIGRP or other and run into a brick wall. (For >example, >> > what >> > > > >does >> > > > > > an router EIGRP really do with the MTU that is passed around in >> > >Updates? >> > > > >;-) >> > > > > > >> > > > > > On a related tangent, will they remove IGRP from CCNA? I'm >> teaching a >> > > > > > custom CCNA class next month, using my own materials. I find it >> > >annoying >> > > > > > that I have to sort of downgrade my materials to teach IGRP >theory >> > and >> > > > > > hands-on instead of the EIGRP I would prefer to teach and is >> already >> > >in >> > > > my >> > > > > > materials. But I think I'm right that CCNA expects IGRP and not >> > EIGRP? >> > > > > > >> > > > > > Thx >> > > > > > >> > > > > > Priscilla >> > > > > > >> > > > > > At 04:02 AM 5/13/02, nrf wrote: >> > > > > > >In-line >> > > > > > > wrote in message >> > > > > > >[EMAIL PROTECTED]">news:[EMAIL PROTECTED]... >> > > > > > > > Nokia might support it, but I have been (fairly reliably) >told >> > >that >> > > > >Cisco >> > > > > > > > will *not* be supporting IGRP as of one of the newest IOS >> > >releases. >> > > > I >> > > > > > > > can't find the announcement on CCO (if there is one), so >take >> > with >> > >a >> > > > > > grain >> > > > > > > > of salt, but a Cisco instructor was quite adamant about this >> last >> > > > >week. >> > > > > > > >> > > > > > >That makes sense, considering it's literally been years since >> I've >> > > > >actually >> > > > > > >seen a bonafide production network running IGRP. So it makes >> sense >> > > > that >> > > > > > >Cisco is finally ditching this dead wood. >> > > > > > > >> > > > > > >But I'm not asking this question because I'm champing at the >bit >> to >> > > > >install >> > > > > > >a mixed Cisco/Nokia IGRP network. No, I'm asking because if >> it's >> > >true >> > > > >that >> > > > > > >Nokia really does support IGRP, then that begs the question - >> what >> > >other >> > > > > > >supposedly Cisco-proprietary technologies are like this too? >I'm >> > not >> > > > > > >talking about situations like what Howard stated where Cisco >> > actually >> > > > has >> > > > >an >> > > > > > >agreement to provide its technology to other vendors (somehow I >> > doubt >> > > > >that >> > > > > > >Cisco and Nokia have such an agreement), but I'm talking about >> > > > >full-blown >> > > > > > >vendor compatibility between some other vendor and Cisco. For > > > >example, >> > > > >does >> > > > > > >anybody know of another vendor that supports, say, EIGRP? Or >> CDP? >> > >Now >> > > > >you >> > > > > > >might say that it would be impossible for another vendor to >> support >> > > > these >> > > > > > >technologies, but, hey, Nokia apparently somehow managed to >> support >> > > > IGRP, >> > > > >so >> > > > > > >why exactly couldn't somebody else support, say, EIGRP? >> > > > > > > >> > > > > > > > >> > > > > > > > JMcL >> > > > > > > > ----- Forwarded by Jenny Mcleod/NSO/CSDA on 13/05/2002 04:44 >> > >pm ----- >> > > > > > > > >> > > > > > > > >> > > > > > > > "nrf" >> > > > > > > > Sent by: [EMAIL PROTECTED] >> > > > > > > > 13/05/2002 01:42 pm >> > > > > > > > Please respond to "nrf" >> > > > > > > > >> > > > > > > > >> > > > > > > > To: [EMAIL PROTECTED] >> > > > > > > > cc: >> > > > > > > > Subject: Is IGRP actually supported by other >> > >vendors? >> > > > > > > > [7:43994] >> > > > > > > > Is this part of a business decision process?: >> > > > > > > > >> > > > > > > > >> > > > > > > > Just found this while surfing around. >> > > > > > > > >> > > > > > > > "As a network device, the Nokia IP330 supports a >comprehensive >> > >suite >> > > > >of >> > > > > > > > IP-routing functions and protocols, including RIPv1/RIPv2, >> IGRP, >> > >OSPF >> > > > >and >> > > > > > > > BGP4 for unicast traffic..." >> > > > > > > > http://www.nokia.com/securitysolutions/platforms/330.html >> > > > > > > > >> > > > > > > > Every piece of literature I've ever read has stated without >> fail >> > >that >> > > > > > IGRP >> > > > > > > > is proprietary to Cisco. Yet here's Nokia brazenly claiming >> that >> > > > they >> > > > >in >> > > > > > > > fact support IGRP. What's up with that? Unfortunately I >> don't >> > >have >> > > > >an >> > > > > > > > Ipso >> > > > > > > > box lying around that I can actually experiment with. Can >> anyone >> > > > >confirm >> > > > > > > > whether this is true and whether it provides complete >> > > > interoperability >> > > > > > > > with >> > > > > > > > Cisco? >> > > > > > ________________________ >> > > > > > >> > > > > > Priscilla Oppenheimer >> > > > > > http://www.priscilla.com >> > > > ________________________ >> > > > >> > > > Priscilla Oppenheimer >> > > > http://www.priscilla.com >> > ________________________ >> > >> > Priscilla Oppenheimer >> > http://www.priscilla.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=44212&t=43994 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
