>Couple additions (corrections).
>
>I just discovered that RIP, IGRP and EIGRP actually use a TTL of 2! (I had
>said that all routing protocol packets use a TTL of 1. OSPF and BGP do.) I
>stick to my main point that routing protocol packets go to
>directly-connected routers and could use just a data-link layer like IS-IS
>does. (Some routing protocols propagate messages to neighbors on the other
>side, but they don't simply forward packets at the IP layer).
>
>Also, I want to say that I should have been more precise, as Howard was:
>
>Routing protocols are layer management protocols at the network layer.
>
>Also, I liked this that he said: Just because a protocol is transmitted
>using a protocol at layer (N) doesn't make the payload protocol layer (N+1).
You first pointed out to me how the official AppleTalk chart has this
confused...ZIP and RTMP at the transport layer???
>
>If we think about it, there are other examples of this being true besides
>management protocols. It's pretty common to see the session-layer NetBIOS
>protocol running on top of LLC, for example. (It's sometimes called NetBEUI
>in this case, but it still has session-layer behavior.)
Other examples include the Enhanced Performance Architecture for
robotic control, which runs the Manufacturing Message Service
directly over LLC Type _3_. In other words, layers 3 through 6 are
null.
Message Posted at:
http://www.groupstudy.com/form/read.php?f=7&i=21092&t=20953
--------------------------------------------------
FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
