""hebn9999"" wrote in message news:[EMAIL PROTECTED] > layer 2 frame has a MTU of 1500 bytes. > how does cisco router propagate router-lsa whose size exceed 1500 > bytes(more than 122 links in one area)?
I've browsed through the other responses, and I did not see this particular piece of information, but it being late perhaps I missed it. I understand this question to mean "what if there are lots of routes, so many that the LSA would end up larger than the MTU" As I read the RFC ftp://ftp.rfc-editor.org/in-notes/rfc2328.txt, beginning on page 194 of said document, OSPF knows the link MTU, and would contruct it's LSA's based on that information. Within the database description packet, there is the "M" bit, which indicates whether or not there are additional database description packets following. The receiving router would see that a particular DDP M bit is marked "on" and would expect more. When the last DDP is received ( M bit marked "off" ) then the current DD sequence number becomes the reference number for the link state database. Future LSA's would have to have a higher sequence number in order to be considered updates. Howard? I "think" this answers the original question, although one never can tell. -Hem- > ______________________________________ > > =================================================================== > [EMAIL PROTECTED] (http://bizsite.sina.com.cn) Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=72173&t=72024 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
