On Thu, 23 Aug 2001, Guy Harris wrote:
> On Thu, Aug 23, 2001 at 10:28:42AM +0800, SrihariK@xxxxxxxxxx wrote:
> > What is difference between ieee and dec spanning tree protocols.
[snippage]
> > If by debugging the config i'm unable to find
> > which protocol is running it there any other wayto find it.
>
> You'd probably have to read the documentation for your networking
> equipment to see which protocol it uses. I am not an expert on this
> (which means "if you reply to this message and send the reply only to
> me, not to the list, you're making a mistake"), but I have the
> impression - possibly incorrect - that only some lines of DEC networking
> equipment used the DEC version rather than the IEEE version.
IIRC the LANbridge 100 came out with the DEC protocol only. It may have
been tweaked later to give you a choice. My recollection is that the two
protocols are not interoperable, not because they are so different, but
because they are similar enough to misinterpret each other's packets.
Kinda like the length vs. protocol-type mess in Ethernet packets. Later
products surely implemented both, but my old networking products catalog
is at home so I can't check just now.
You might find some discussion in Perlman's _Interconnections_, but again
my copy is at home so I can't say for sure.
> > is dec stp is required for decnet related protocols or its just an algorithm
> > developed by dec.
>
> As far as I know, it's just the protocol developed by DEC.
DECnet shouldn't know the difference -- see the definition of "bridging".
Same story for LAT, LAD/LAST, etc. STP is for bridges to communicate
topology knowledge to each other, and other nodes shouldn't be aware of
STP or bridging. You only need to know the DEC version of STP if you want
to snoop the spanning-tree algorithm among bridges that speak it, and I
would imagine that they are becoming quite rare.
--
Mark H. Wood, Lead System Programmer mwood@xxxxxxxxx
Make a good day.
