Brilliant! Pierre-Alex
-----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Bernard Omrani Sent: Tuesday, December 25, 2001 7:21 PM To: [EMAIL PROTECTED] Subject: RE: IP classless command [7:30056] For a simple explanation if IP classless, see: http://www.networkking.net/out/ipclassless.htm Bernard > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] > Sent: Tuesday, December 25, 2001 12:41 PM > To: [EMAIL PROTECTED] > Subject: Re: IP classless command [7:30056] > > IP CLASSLESS is a little hard to understand. Even Cisco is very vague on > this. Once a > TAC engineer just told me that the command just makes routing better. > Here > is what I > believe happens. > > If you don't have the "IP CLASSLESS" command defined in a Cisco router > then > the router > will not forward any packets towards a default route for any subnets of a > classfull > network that the router thinks are local. For instance. > > Rtr A local net 10.1.0.0/24. > 192.168.1.0 interconnects routers a and b > RTR B (sends default network only to RTR A and RTR C) > 192.168.2.0 interconnects routers b and C > RTR C local net 10.2.0.0/24 > Note how 10.0.0.0 is split by the 192.168.1.0 and 192.168.2.0 networks. > > In the above example if RTR A gets a packet destined for 10.2.0.1, but it > does not have > the "IP CLASSLESS" command defined then RTR A will drop the packets. > > If you include the IP CLASSLESS command then the packets will be forwarded > to the > default router b. > > I hope this helps > Mike Paulson > Network Architect > Infrastructure Design Systems LLP > > > Hunt Lee wrote: > > > Can anyone please explain to me what is "ip classless" used for? I > looked > > it up on the Caslow book, and it states that by enabling IP classless, > it > > allows one to override the contiguous subnet rule and allow the router > to > > look for the longest match beyond the listed subnets. > > > > But I still don't understand what it means? Can anyone give me some > > examples? > > > > Thanks in advance. > > > > Best Regards, > > Hunt Lee > > IP Solution Analyst > > Cable & Wireless > > [GroupStudy.com removed an attachment of type text/x-vcard which had a > name > of michael.paulson.vcf] Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=30097&t=30056 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
