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Re: [Bridge-mib] VLAN-ID
As Andrew says, VLAN-ID is defined in IEE Std 802.1Q-1998. That makes
it an IEEE object and so we should follow the specification of the
IEEE. I see this as the fundamental principle and anything that goes
against that I would regard as wrong.
Tom Petch
nwnetworks@dial.pipex.com
----Original Message-----
From: Andrew Smith <ah_smith@acm.org>
To: 'Eduardo Cardona' <e.cardona@CableLabs.com>
Cc: mibs@ops.ietf.org <mibs@ops.ietf.org>; bwijnen@lucent.com
<bwijnen@lucent.com>; bridge-mib@ietf.org <bridge-mib@ietf.org>;
'Romascanu, Dan (Dan)' <dromasca@avaya.com>
Date: 19 February 2003 23:46
Subject: RE: [Bridge-mib] VLAN-ID
>Eduardo,
>
>Suggest you refer to the IEEE spec (e.g. IEEE 802.1Q-1998 section
>9.3.2.3 although I think there is a newer draft in progress for which
I
>do not have the exact info). Note that it specifically says there
that
>the VID is an "unsigned binary number" so I don't know why the SYNTAX
>would be INTEGER rather than Unsigned32. Hex FFF (4095, not -1) is
>reserved for "implementation uses" - I would suggest that this is the
>appropriate one to choose for "special semantics". The value 0 is not
>appropriate since you can very validly have packets on the wire
carrying
>0 as the VID and you may very well want to place filters or counters
on
>such packets. At some point, DOCSIS should probably try to align with
>the 802.1Q specification (or else not pretend that it is compatible).
>
>Note also that use of a "mask" on VID values is inappropriate (it
>implies some local manager's allocation policy that is not likely to
be
>universally useful): a list of individual values or a numerical range
>would be more appropriate.
>
>I would suggest that RFC 2613 is wrong not to allow for counting of
>VID=0 packets on the wire by a probe.
>
>Now 802.1Q does also say that the VID values 0 and FFF "shall not be
>used in any management operation" and I'm not entirely sure why we
>included this statement.
>
>To answer Bert's original question, several TCs will be needed to
>capture all of the semantic differences between on-the-wire,
>internal-to-a-bridge and allowed-in-management-operations uses of
this
>VID/VLAN-ID/12-or-more-bit thing. I think that RFC 2674 is consistent
>with 802.1Q and should be the place to start for extracting common
TCs.
>
>Hope that helps,
>
>Andrew Smith
>
<snip>
>>
>> > -----Original Message-----
>> > From: Wijnen, Bert (Bert) [mailto:bwijnen@lucent.com]
>> > Sent: Wednesday, February 19, 2003 5:14 PM
>> > To: bridge-mib@ietf.org
>> > Subject: [Bridge-mib] VLAN-ID
>> >
>> >
>> > Bridgemibbers....
>> >
>> > I do not see much (if any activity lately) :-(
>> >
>> > But I have a question.
>> >
>> > I see a VLAN ID represented in various forms:
>> >
>> > - draft-ietf-bridge-ext-v2-01.txt
>> > VlanId ::= TEXTUAL-CONVENTION
>> > STATUS current
>> > DESCRIPTION "A 12-bit VLAN ID used in the VLAN Tag
header."
>> > SYNTAX INTEGER (1..4094)
>> > - somehwere I found:
>> > dot1vProtocolPortGroupVid OBJECT-TYPE
>> > SYNTAX INTEGER (1..4094)
>> > MAX-ACCESS read-create
>> > STATUS current
>> > DESCRIPTION "The VID associated with a group of protocols
for
>> > each port."
>> > REFERENCE "IEEE 802.1v clause 8.4.4, 12.10.1.2"
>> >
>> > - In a DOCSIS document I find:
>> > docsQosPktClassVlanId OBJECT-TYPE
>> > SYNTAX Integer32 (0..4095)
>> > MAX-ACCESS read-only
>> > STATUS current
>> >
>> > - In the framework PIB (draft-ietf-rap-frameworkpib-09.txt) I
find:
>> >
>> > frwk802FilterVlanId OBJECT-TYPE
>> > SYNTAX Integer32 (-1 | 1..4094)
>> > STATUS current
>> > DESCRIPTION
>> > "The VLAN ID (VID) that uniquely identifies a VLAN
>> > within the device. This VLAN may be known or unknown
>> > (i.e., traffic associated with this VID has not yet
>> > been seen by the device) at the time this entry
>> > is instantiated.
>> >
>> > Setting the frwk802FilterVlanId object to -1
>> indicates that
>> > VLAN data should not be considered during traffic
>> > classification."
>> >
>> > - In rfc2613 I find:
>> > smonVlanIdStatsId OBJECT-TYPE
>> > SYNTAX Integer32 (1..4094)
>> > MAX-ACCESS not-accessible
>> > STATUS current
>> > DESCRIPTION
>> > "The unique identifier of the VLAN monitored for
>> > this specific statistics collection.
>> >
>> > Tagged packets match the VID for the range between
>> 1 and 4094.
>> > An external RMON probe MAY detect VID=0 on an Inter
Switch
>> > Link, in which case the packet belongs to a VLAN
>> determined by
>> > the PVID of the ingress port. The VLAN to which
>> such a packet
>> > belongs can be determined only by a RMON probe
>> internal to the
>> > switch."
>> > REFERENCE
>> > "Draft Standard for Virtual Bridged Local Area Networks,
>> > P802.1Q/D10, chapter 3.13"
>> >
>> > - In RFC2674 I find:
>> > VlanIndex ::= TEXTUAL-CONVENTION
>> > STATUS current
>> > DESCRIPTION
>> > "A value used to index per-VLAN tables: values of 0 and
>> > 4095 are not permitted; if the value is between 1 and
>> > 4094 inclusive, it represents an IEEE 802.1Q VLAN-ID with
>> > global scope within a given bridged domain (see VlanId
>> > textual convention). If the value is greater than 4095
>> > then it represents a VLAN with scope local to the
>> > particular agent, i.e. one without a global VLAN-ID
>> > assigned to it. Such VLANs are outside the scope of
>> > IEEE 802.1Q but it is convenient to be able to manage
them
>> > in the same way using this MIB."
>> > SYNTAX Unsigned32
>> >
>> > - IN RFC2674 I also find
>> > VlanId ::= TEXTUAL-CONVENTION
>> > STATUS current
>> > DESCRIPTION
>> > "A 12-bit VLAN ID used in the VLAN Tag header."
>> > SYNTAX INTEGER (1..4094)
>> >
>> > Not sure I found all occurances.
>> >
>> > So my question is: what is the CORRECT spec, and could we try to
>> > define one (or a few) TC(s) that everyone else can IMPORT and
use.
>> >
>> > Bert
>> > _______________________________________________
>> > Bridge-mib mailing list
>> > Bridge-mib@ietf.org
>https://www1.ietf.org/mailman/listinfo/bridge-mib
>