At 4:47 AM +0000 1/16/03, Matthew Webster wrote: >Hi all, > >just a minor (I think) question. In the OSPF LSR message, why does the LS >type have 4 bytes to describe it, when there are only 5 different values? Am >I missing something? > >TIA. > >cheers, >Matthew.
One of the design goals of OSPF, as opposed to ISIS, was machine processing efficiency, even at the cost of flexibility and memory. OSPF designers strived to put things on 32-bit, then 16-bit, then 8-bit alignments because this was really faster on processors of the time. ISIS, however, went with the more flexible TLV approach, which needs more processing to be parsed. If we were doing a brand-new IGP today, I suspect the data structuring would be more like the chained fixed-length fields of the IPv6 header. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=61192&t=61176 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
