Re: 10G ethernet and 802.1q

Just off the topic guys..but the Algorhyme suddenly came in to my mind and
just copying in here..

Algorhyme

I think that I shall never see
A graph as lovely as a tree.

A tree which must be sure to span.
So packets can reach every LAN.

First the root must be selected.
By ID, it is elected.

Least cost paths from Root are traced.
In the tree these paths are placed.

A mesh is made by folks like me.
Then bridges find a spanning tree.

-- Radia Perlman, Interconnections

Tharak Abraham Luke

On Mon, Apr 6, 2009 at 4:38 PM, Paul Cosgrove <paul.cosgrove_at_gmail.com>wrote:

> Hi Pavel,
>
> Reza's question was about the likely intention behind two sentences
> apparently taken from a larger document. From those two lines you have
> formed a negative opinion of the author, but I wonder if it is fair to judge
> them based on two lines taken in isolation.
> You have suggested that they author may have had load balancing in mind,
> and I also believe that is likely. We differ in that you believe the
> author was confusing protocols, whereas I do not think the text supports
> that conclusion.
>
> Paul.
>
>
> Pavel Bykov wrote:
>
>> While we could probably continue to look into more more depth and in a
>> court-hearing-style technicalities, we are still speculating on what did
>> the
>> original author mean by that statement. And that would also be a point
>> against that author for not being specific enough.
>>
>> On Mon, Apr 6, 2009 at 2:34 PM, Paul Cosgrove <paul.cosgrove_at_gmail.com
>> >wrote:
>>
>>
>>
>>> Thanks Pavel, the link helps to clarify my point. MST is defined in
>>> 802.1Q, and it is likely that the quote is referring to that. With that
>>> in
>>> mind perhaps your judgement of the author may be a little harsh. While
>>> the
>>> last amendments were made to 802.1Q in 2005, that is now four years old.
>>> There are various other draft amendments which are likely to be added in
>>> the next version of the standard (see 802.1Qau, 802.1Qbb etc). As
>>> network
>>> usage patterns and requirements change, the standards change to support
>>> them.
>>>
>>> I do not think it is correct to say that 802.1w replaced 802.1d. 802.1w
>>> was the name of the proposed ammendment to 802.1d. 802.1d-2004 amended
>>> 802.1d so that STP was removed from the spec, and RSTP replaced STP.
>>> See
>>> http://www.ieee802.org/1/pages/802.1w.html
>>> "This supplement to ISO/IEC 15802-3:1998 (IEEE Std 802.1D-1998) defines
>>> the
>>> changes necessary to the operation of a MAC Bridge in order to provide
>>> rapid
>>> reconfiguration capability."
>>>
>>> Proposed amendments, such as 802.1s or 802.1w, are defined separately
>>> before they are incorporated into the standard and I think that is where
>>> the
>>> confusion is arising here.
>>>
>>> Paul.
>>>
>>>
>>>
>>> Pavel Bykov wrote:
>>>
>>>
>>>
>>>> Paul, to be extremely technical, the current state of .1Q is
>>>> 802.1Q-2005,
>>>> which is available here:
>>>> http://standards.ieee.org/getieee802/download/802.1Q-2005.pdf and it
>>>> incorporates all of the most recent amendments, including 802.1s,
>>>> 802.1v,
>>>> etc. And it is one of the most recent standards out there.
>>>>
>>>> In tech talk, I have always heard 802.1Q referring primarily to tagging
>>>> mechanism and it's properties, not it's manipulation, like spanning
>>>> trees,
>>>> classification, management, etc.
>>>>
>>>>
>>>> P.S.: 802.1d was not improved per se, but instead replaced by more
>>>> advanced
>>>> 802.1w
>>>>
>>>>
>>>>
>>>> On Sun, Apr 5, 2009 at 9:34 PM, Paul Cosgrove <paul.cosgrove_at_gmail.com
>>>>
>>>>
>>>>> wrote:
>>>>>
>>>>>
>>>>
>>>>
>>>>
>>>>> The standards are not static if course. There are often proposals to
>>>>> update
>>>>> existing standards, or to introduce new ones to replace them. TCP
>>>>> extensions for high performance were published in 1992; ECN and the
>>>>> authentication option being more recent examples Changes to 802.1d
>>>>> mean
>>>>> that it is not as slow as it once was, RSTP having replaced the older
>>>>> STP
>>>>> in
>>>>> 2004.
>>>>>
>>>>> There have also been various changes to 802.1Q protocol. It was
>>>>> originally
>>>>> specified according to the old 802.1d standard, but MSTP was included
>>>>> in
>>>>> the
>>>>> ammendments added to the specification in 2003.
>>>>>
>>>>> The full context would make it clearer, but perhaps the author is using
>>>>> layer 3 links with dynamic routing, instead of Layer 2 with MSTP.
>>>>> Paul.
>>>>>
>>>>>
>>>>> Pavel Bykov wrote:
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>> TRILL is the way to go, so is the OTV. but it only builds upon 802.1q,
>>>>>> and
>>>>>> does not replace it in any sense.
>>>>>> Whoever said that "the 802.1q...is old and does not support the high
>>>>>> bandwidth requirements for new services / applications." is a moron.
>>>>>> First of all, the sentence does not makes sense. TCP is really old,
>>>>>> like
>>>>>> 30
>>>>>> years old, but we are not in a hurry to replace it. OLD does not mean
>>>>>> BAD.
>>>>>> Second, it does not mention why it does not support the high
>>>>>> bandwidth.
>>>>>>
>>>>>> What author may have meant, if he had any network experience, is that
>>>>>> 802.1D
>>>>>> (notice how .1D is not .1Q) is a protocol with many shortcomings,
>>>>>> including
>>>>>> slow convergence and absence of load balancing, which has to be
>>>>>> provided
>>>>>> by
>>>>>> other standards, like 802.1AX, PVST, etc. And that routing will be
>>>>>> used.
>>>>>>
>>>>>> But 802.1Q has no equal at this time. If you just want to use routing
>>>>>> then
>>>>>> that's fine, but it is substantially different than L2 service
>>>>>> enablement
>>>>>> which 802.1Q provides.
>>>>>>
>>>>>> P.S. forget ISL.
>>>>>>
>>>>>>
>>>>>> On Wed, Apr 1, 2009 at 9:57 AM, Evan Weston <evan_weston_at_hotmail.com>
>>>>>> wrote:
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>> I went to a Cisco event yesterday and one of the presenters mentioned
>>>>>>> TRILL
>>>>>>> https://cisco.hosted.jivesoftware.com/message/2747 thought it was
>>>>>>> interesting...
>>>>>>>
>>>>>>> -----Original Message-----
>>>>>>> From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On Behalf
>>>>>>> Of
>>>>>>> Shahid Ansari
>>>>>>> Sent: Wednesday, 1 April 2009 4:54 PM
>>>>>>> To: Hash Aminu
>>>>>>> Cc: Reza Toghraee; ccielab_at_groupstudy.com
>>>>>>> Subject: Re: 10G ethernet and 802.1q
>>>>>>>
>>>>>>> Hash,
>>>>>>>
>>>>>>> worked with ISP and havent used ISL ,dot1q is best to go(q in q
>>>>>>> tunnel)
>>>>>>> 1q also a standard across different vendors and guaranteed to work
>>>>>>> between
>>>>>>> different vendor equipments whereas ISL fails :)
>>>>>>> regarding the VLANS ,who want to create more than 1K/4k Vlans?
>>>>>>>
>>>>>>> Thanks
>>>>>>> Shahid
>>>>>>>
>>>>>>> On Tue, Mar 31, 2009 at 3:11 PM, Hash Aminu <hashng_at_gmail.com>
>>>>>>> wrote:
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>> Reza/Shahid,
>>>>>>>>
>>>>>>>> while i will agree with you that most of them are implying to cisco
>>>>>>>> solution, I am aware of using 802.1q in cisco Gears can be less
>>>>>>>> scalable
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>> as
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>> the # of VLANs grows..hence you will run out of virtual ports (total
>>>>>>>> #
>>>>>>>> of
>>>>>>>> Vlans passing thru a .1q trunk X the number of ports)..mostly the
>>>>>>>> limits
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>> is
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>> 6k per any line card.
>>>>>>>>
>>>>>>>> HTH
>>>>>>>>
>>>>>>>> Hash
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>
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>>>>>>
>
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Received on Mon Apr 06 2009 - 17:25:23 ART