RE: [RPRWG] Promiscuous mode
Sam,
Can you provide more information regarding how promiscuous
mode is intended to be used in RPR. Promiscuous mode in 802.3
is fine for supporting transparent bridges supporting 802.3
network interfaces. The 802.3 MAC passes all received frames
up to the transparent bridge client. Promiscuous mode causes problems for
transparent bridges attached to RPR. These problems were
presented in previous meetings.
At last meeting we accepted comment #951 defining rxfilter
which defines an RPR MAC receive filter. Rxfilter controls
when receive frames are passed up to the client.
rxfilter takes on two values -
Basic - receive unicast frames where preHEC DA matches station's MAC
address, broadcast, multicast
Flood - BASIC + frames where the frame.FF is either bidirectional or
unidirectional.
The basic setting is intended for frame reception by a host. The flood
setting is
intended for frame reception by a transparent bridge. The flood setting
differs
from promiscuous mode in that unicast frames to some other MAC address
are not copied to the RPR MAC client. This is the required behavior
for a transparent bridge client attached to RPR ring.
Promiscuous mode might be useful for an RPR MAC residing in a piece
of test equipment in which case the scope of promiscuous mode would
not be just limited to data frames, but includes control as well.
If promiscuous mode is needed for diagnostic or some other purpose, it is
probably
worth proposing at the next meeting.
thanks,
robert
ps. This complements Peter Jone's email on this topic.
> -----Original Message-----
> From: Anoop Ghanwani [mailto:anoop@xxxxxxxxxxxxxx]
> Sent: Wednesday, March 26, 2003 2:33 PM
> To: 'Blakey, Sam'; 'stds-802-17@xxxxxxxx'
> Subject: RE: [RPRWG] Promiscuous mode
>
>
>
>
> Sam,
>
> I agree with your comment. I think the MAC should
> check whether or not the receiver is in promiscuous
> mode before copying a flooded frame from the ring
> that has a unicast DA not equal to its own.
>
> -Anoop
>
> -----Original Message-----
> From: Blakey, Sam [mailto:Sam.Blakey@xxxxxxx]
> Sent: Wednesday, March 26, 2003 11:10 AM
> To: 'stds-802-17@xxxxxxxx'
> Subject: [RPRWG] Promiscuous mode
>
>
> Hi,
> At the last meeting submitted a comment to include
> promiscuous mode in the
> state table governing frame reception. The reply to the
> comment was that
> Ethernet (802.3) only has promiscuous mode in the MIB. Now
> that I look more
> carefully, in the frame reception normative clause (5.2.4.3 Receive
> variables and procedures) there is a condition that checks
> promiscuous mode
> and determines whether to receive a frame depending on
> whether in this mode.
> So, if we're taking 802.3 as a guideline for the required contents for
> promiscuous mode, although there is no actual description of
> the mode as a
> subclause needed, it should be included in the frame
> reception logic (as per
> comment submitted).
> Opinions?
> Thanks,
> Sam
> Sam Blakey
> Integrated Device Technology, Inc.
> 2975 Stender Way,
> Santa Clara, CA 95054
> Tel: (408) 330-1432
> Fax: (408) 492-8649
> E-mail: sam.blakey@xxxxxxx
> Visit the IDT web site www.idt.com
>