And a more detailed reading of Comer found these statements:
Protocols like ARP belong in the network interface layer.
Application programs as well as all protocol software from the Internet
layer upward use only IP addresses. The network interface layer handles
physical addresses.
Comer, for those of you just joining says that broadly speaking, TCP/IP has
four conceptual layers:
Application
Transport
Internet
Network Interface
Priscilla
At 04:35 PM 6/14/01, Priscilla Oppenheimer wrote:
>At 03:42 PM 6/14/01, Dr Rita Puzmanova wrote:
> >Thank you all for valid perspectives. Yet my original question (I had on
> >mind but perhaps not clearly worded) is still unanswered. I will
> >rephrase it:
> >
> >Does ARP operates at network interface layer or internet layer of TCP/IP
> >protocol stack?
>
>Where are you getting those names for TCP/IP layers? I don't see them in
>early TCP/IP RFCs.
>
>The original ARP RFC is here, and it doesn't use those terms:
>
>http://andrew2.andrew.cmu.edu/rfc/rfc826.html
>
>The early TCP standard says the four layers are higher-level, TCP, internet
>protocol, and communication network. A search of the early IP standard
>didn't find the word layer at all!? ;-)
>
>Here's my guess. Check the discussion of layering in Douglas Comer's
>Internetworking with TCP/IP, Volume I. He says that "broadly speaking,
>TCP/IP software is organized into four conceptual layers: application,
>transport, Internet, and Network Interface."
>
>Since 80% of the people on the planet (rough estimate) that learned TCP/IP
>learned it from Comer, including authors and tech writers, this conceptual
>drawing became "fact" and is explained as THE DOD model, even though DOD
>documents don't have such a model. That's my guess.
>
>Priscilla
>
>
> >Just forget anything else (in particular OSI concepts) - concentrate on
> >TCP/IP. To my opinion every protocol must belong somewhere (otherwise
> >the whole layering concept would be useless and could not work), it
> >cannot be an "interface" (it is a layer protocol, not an interlayer
> >protocol within a single system).
> >
> >No matter whether IETF currently bothers about its own layering system -
> >at the beginning they for sure managed to fit the pieces in the puzzle
> >(I mean protocols) according to their original, simple
> >4-layer-architecture.
> >
> >Sorry for being soooo persistent ;-)
> >
> >Rita
> >
> >Dr Rita Puzmanova wrote:
> > >
> > > Hi all,
> > >
> > > Trivial yet fundamental question. I have seen ARP described as part of
> > > the network (internet) layer so many times that I have started to
> > > believe it belongs there (although I know well that it operates "as if"
> > > the Layer 2 protocol - as per OSI RM). Now I have eventually come
across
> > > Doug Comer's statement: "It's part of the network interface layer."
> > >
> > > I should not ask where the truth is but still I will. That would mean
> > > quite a lot of books are incorrect in this (including Cisco materials).
> > >
> > > Rita
>________________________
>
>Priscilla Oppenheimer
>http://www.priscilla.com
Message Posted at:
http://www.groupstudy.com/form/read.php?f=7&i=8627&t=8335
--------------------------------------------------
FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
