Physical layer of the OSI reference model...

[LanEvoVI]

I'm studying for an exam I've got tomorrow and I'm kind of puzzled as to what the reconciliation layer (a little sublayer of the Physical layer) does...

My notes are kinda non-specific in what it does...if someone could help me out it'd be appreciated...

 

[RagManX]

Just went through the entire physical layer chapter in Tanenbaum's Computer Networks and see no reference to the reconcilation layer. What do your notes say on it? Maybe I've heard a different name used for it. Can't help right now, though.

RagManX

 

[kylef]

I can just about guarantee that you will not see that on your exam.

The Reconciliation layer is usually a sublayer in Layer 2 (data link layer). It sits between layer 2 and layer 1, and supposedly provides a "translation interface" between the two so that the Mac layer can be used with any physical layer that the Mac supports. For instance, if you have a Gigabit ethernet MAC layer, you can use 1000-base-T, 1000-base-SX, 1000-base-TX, with relative impugnity.

Note that this is similar, in a way, to the LLC of the 802.x series of layer 2 protocols. The LLC of all of the IEEE 802.x protocols are interchangeable, so that you can implement a single LLC and use ANY MAC/phy layer with your LLC implementation.

But honestly, I don't think that the "translation interface" that it provides is anything more than just a nice block people can draw on their protocol stack diagrams. I don't think it really DOES anything more than provide an interface. I don't think it merits its own block!

 

[LanEvoVI]

Thanks a lot! That makes my notes a whole bunch clearer. And seeing as how most of the info we covered after the midterm was on the Data Link and Phy layers...this info might come in handy.