>Just an open question ? > >We read, learn and teach Routing protocols are at the >NETWORK layer of the famous OSI model...
Protocol numbers are not an OSI concept, but a concept of IP. In any case, it is the function of a protocol that determines its layer, not necessarily what it runs over. Routing protocols are intended to provide management and control services at the network layer. There was a relatively recent thread on this; check the archives. > >But they have PROTOCOLS NUMBERS - TRANSPORT LAYER(such >as IGRP protocol 9, EIGRP protocol 88 and OSPF >protocol 89)and APPLICATION PORTS values - APPLICATION >LAYER (RIP uses port 520 and BGP4 uses port 179) >indicating they work in the upper layers and not in >the network layer, although the result is shown int >the NETWORK layer... > >So may question is... > >Do they really operate at LAYER 3 ? > >Warm regards, > >Jose Luis De Abreu Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=29141&t=29139 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
