Sorry to be a pain
let me see if i have this correct...
routing protocols do the following
manage links
exchange data
route packet
update each other
what his instructor is saying is that some of these functions work at
different "layers" of the OSI model...YES i know i shouldn`t be using that
as a reference but for this argument i will...sorry...
so tell me OSPF....what "layers" would the above function be compared to
please .....i have a major headache now as i thought i knew it
steve CCIE... CCSI... C.C. Senior`
my little joke
>From: "Howard C. Berkowitz" <[EMAIL PROTECTED]>
>Reply-To: "Howard C. Berkowitz" <[EMAIL PROTECTED]>
>To: [EMAIL PROTECTED]
>Subject: RE: routing protocols vs Tcp/ip model
>Date: Sat, 11 Nov 2000 08:11:34 -0500
>
>Your instructor is one of the all-too-large group of people who try
>to coerce things into a simplistic OSI model. Priscilla calls this
>coercing protocols into OSI layers. It's really not the fault of OSI,
>because there are documents that supplement the original model, such
>as the Rout(e)ing Framework, Internal Organization of the Network
>Layer, Management Annex, etc.
>
>The OSI stack principally was drawn to show how standard
>communications service user applications, which run on top of the
>service interface to the application layer. Management was something
>of an afterthought, and what is called system management -- think
>SNMP, or the OSI rough equivalent, CMIP -- does indeed involve an
>application layer protocol and a management application above it.
>
>Routing, error notification, etc., are considered layer management.
>There is nothing "above" them; they are part of the infrastructure
>for a given layer. So,all of them are logically layer 3.
>
>The issue of the mechanism they use to transfer information between
>them is independent of the layer they manage. In Chuck's table
>below, EIGRP and OSPF do have transport functions that are part of
>their own design--which have a TCP-like flavor. For that matter, ISIS
>runs directly over data link.
>
>>Recently an instructor in a class I was taking said something I found
>>interesting. I hope I can do justice to his words.
>>
>>Network layer: IP IP IP
>>Transport layer: TCP UDP
>>Application layer: BGP RIP EIGRP, OSPF, IGRP
>>
>>In other words, he suggested that routing protocols are application layer,
>>and use the chosen transport or network layer protocols to communicate.
>>Other reading I have done kinda says this in other ways. RIP uses UDP port
>>500. BGP, as we all know, uses TCP.
>>
>>Does this make sense?
>>
>>Chuck
>
>A post I made yesterday might help:
>At 4:16 PM -0500 11/10/2000, Howard C. Berkowitz wrote:
>>At 12:22 PM -0800 11/10/2000, Julian Eccli wrote:
>>>Does anyone know the definition of Control Plane from a generic
>>>routing protocol
>>>standpoint? Is it the same definition as in ATM? I have heard
>>>references to
>>>control planes in various talks but they were not specific to ATM.
>>>
>>
>>Unfortunately, it isn't as well-specified in IP routing as in the
>>B-ISDN/ATM architecture. Many IP discussions merge what that
>>architecture calls the control and management plane.
>>
>>Personally, I think merging the two is rather unfortunate. In IP
>>networks, I consider control plane protocols those that are used for
>>signaling between hosts and ingress/egress routers. Examples: ARP,
>>IGMP. Another way to think about them is that they serve a
>>user-to-network role.
>>
>>I consider pure management plane protocols to those used between
>>routers: BGP, OSPF, EIGRP, RIP, etc. Arguably, these have a
>>network-to-network role.
>>
>>There are protocols that don't neatly fit, such as RSVP and ICMP. I
>>suppose they are control plane when host initiated and management
>>plane when router initiated, but that doesn't always work and is
>>ugly anyway.
>
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