Kevin Cullimore wrote: > > ----- Original Message ----- > From: "Priscilla Oppenheimer" > To: > Sent: 03 August 2002 1:47 pm > Subject: RE: RIP/IGRP Routing Simulator? [7:50586] > > > > A protocol analyzer would let you generate packets. Capture > some RIP and > > IGRP updatess so you know what they look like, change and add > network > > numbers, and then send them out again. A good analyzer will > recalculate > the > > IP checksum for you. (Also, the UDP checksum in the case of > RIP). > > If the pc/microcomputer you were planning on using is > expendable, you might > consider putting a unix variant on it, as the range of > available simulators > is a bit larger. Both the simulator & the analyzer approach > aren't much help > with at least one part of the certification preparation process: > > altering configuration parameters on the cisco IS & verifying > that the > packet structure & content match the expectations you are > developing.
He can do that with a protocol analyzer. I don't see your point I guess. (He did say he has some routers.) Changing Cisco IOS configs and capturing with an analyzer is an excellent way to see how protcols really behave. The packet strucutre won't change usually, but the contents will change. > > Even in the case of proprietary routing protocols, it remains > an open > question whether or not the behavior of the vendor's software & > hardware > match the descriptions set forth in the specification (As > usual, the > proprietary specifications themselves remain closed). IGRP protocol specifications are easy to learn even it is technically "proprietary." Of course, the protocol analyzer vendors have all learned it (and EIGRP) quite well. Sniffer does a particulary good job of decoding EIGRP. IGRP, by the way, is completely specified in this old paper from Rutgers, which Cisco never objected to: http://www.cisco.com/warp/public/103/5.html EIGRP protocol specification info is harder to find, though from an operations viewpoint, TAC has some terrific papers here: http://www.cisco.com/warp/public/103/eigrp3.html Priscilla > > In the case of allegedly open standards, enough details are > left up to the > vendor that this kind of hands-on research is essential in > order to avoid > hitting a tinted-glass ceiling as far as a deep understanding > of networking > is concerned, which is itself nearly essential when in the > midst of a supply > glut. > > I suspect the standards themselves are similarly partially > disassociated > with the principles that undergird them, but I lack examples. > > > > Of course, if you could afford a good analyzer, you could > afford some new > > routers too, though! ;-) Does anyone know if the free > analyzers like > > Etherreal will let you generate packets? > > As far as ethereal is concerned, not as of the spring 2002 > version. > > > Priscilla > > > > > > Sparky Nelson wrote: > > > > > > What I am looking for is a Windows program that I can > connect > > > to a Cisco > > > router that will send out RIP routing updates. Would love to > > > send out a a > > > group of 5 to 10different routes to illustrate routing > without > > > using > > > loopback addresses. If I need to use loopbacks I will but > would > > > prefer the > > > routes were coming into the rouing environment from an > external > > > source > > > rather than an internal router. I figure it won't be hard to > > > get a RIP > > > simulator, I really don't expect to get anything that will > send > > > IGRP routing > > > information because of the propritary nature of IGRP. > > > > > > Thanks, > > > > > > Kevin > > Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=50611&t=50586 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
