[RPRWG] RE: Question about the topology discovery in DVJ
Jim,
Relative to the topology discovery,
> Got a quick question for the discovery topology in DVJ.
> How the packet is stripping after it get on the ring?
The topology discovery packets are sent to the adjacent neighbor,
where it is always stripped/modified/transmitted and/or modified
on the pass-through. Either implementation option meets
the stated architectural objectives.
These packets are continually transmitted at a periodic rate.
Given the typical latencies, its possible to send these frequently
enough so that protection-event notification (i.e. change
in discovery information), heartbeat detection, and arbitration
information information can be placed within the same frame.
If your question is relative to the encoding, that's a detail.
Could be a header bit, but I would prefer to use a specific ID
address for the "stripped at next station" address.
Synchronizing periodic transmissions (to reduce latency) is TBD.
A reasonable argument is to let each station run asynchronously,
as additional latency can be easily compensated by sending it
at a slightly higher rate.
The key point is that things simply "flow" forever, with no
special transitions or broadcast signals generated at specific
spots. This eliminates the problems associated with timeouts,
packet loss, node disappearance, etc. As long as the through
station processing time is much less than the link-transmit time,
there is also no benefit to using a more complex broadcast
scheme.
I think I have answered a few questions, but not sure if these
questions really correspond to the question that was asked.
Please let me know if more clarity is required.
DVJ
David V. James, PhD
Chief Architect
Network Processing Solutions
Data Communications Division
Cypress Semiconductor
110 Nortech Parkway
San Jose, CA 95134
Work: +1.408.942.2010
Cell: +1.650.954.6906
Fax: +1.408.942.2099
Work: djz@xxxxxxxxxxx
Base: dvj@xxxxxxxxxxxx
> -----Original Message-----
> From: Jim Kao [mailto:jkao@xxxxxxxxx]
> Sent: Thursday, January 10, 2002 1:19 PM
> To: djz@xxxxxxxxxxx
> Subject: Question about the topology discovery in DVJ
>
>
> David,
>
> Got a quick question for the discovery topology in DVJ.
>
> How the packet is stripping after it get on the ring?
>
> Thanks,
>
> Jim
>
>