Re: Jumbo Frames in 10GbE?
- To: bbooth@xxxxxxxxxx, gwinn@xxxxxxxxxx, l_d_miller@xxxxxxxxxxxxx
- Subject: Re: Jumbo Frames in 10GbE?
- From: ted@xxxxxxxxxx (Ted Schroeder)
- Date: Mon, 21 Jun 1999 13:41:55 -0700
- Cc: stds-802-3-hssg@xxxxxxxx
- Sender: owner-stds-802-3-hssg@xxxxxxxxxxxxxxxxxx
Please check the document Error Characteristics of FDDI by Raj Jain.
The CRC-32 algorithm breaks down at 11454 octets given the error
characteristics he analyzes in his paper.
Alteon WebSystems, Inc.
>I have heard some folk lore that the CRC-32 algorithm rather suddenly falls
>apart (in terms of high detection rate) above the present maximum Ethernet
>block size (1518 bytes).
>Indeed, there has been some pleas for "no superpackets, please!" on this
>This should be carefully checked before making any great leaps, tempting
>though it may be from an overhead perspective.
>From: Joe Gwinn <gwinn@xxxxxxxxxx>
>To: Booth, Brad <bbooth@xxxxxxxxxx>
>Cc: HSSG_reflector (E-mail) <stds-802-3-hssg@xxxxxxxx>
>Date: Monday, June 21, 1999 12:34 PM
>Subject: Jumbo Frames in 10GbE?
>>At 4:24 PM 99/6/17, Booth, Brad wrote:
>>>Just a small point. One of the objectives that passed with greater than
>>>75% in Coeur d'Alene was to "preserve minimum and maximum FrameSize of
>>>current 802.3 Std."
>>I don't know that the issue is going to stay decided all that long, based
>>on the recent article "Jumbo Frames gather support" (Jeff Caruso, Network
>>World, 14 June 1999, page 6), which states that IETF has published a
>>working document proposing that ethernet frames be made larger than the
>>current 1,500-byte maximum, the basic rationale being to reduce the packet
>>rate and thus load on packet-handling components of the system. In short,
>>this is a system issue, and cannot really be decided solely at the MAC
>>If jumbo frames are to come, 10GbE would be a logical place to start.
>>The issue will ultimately be decided by an IEEE Ballot Group, not a
>>Plenary. If the market is really going to bigger packets, as this article
>>implies, it will be hard to resist.
>>The above is in response to the following:
>>> >Issues 3 - Bit Error Rate
>>> >The assumption will be that this is 10-12. If someone wishes to
>>> >this they should bring a presentation to the next meeting
>>> detailed reasoning why this needs to change.
>>> It strikes me that the issue of larger maximum packet sizes will
>>> come up, just as it did for GbE. If 10GbE goes to 9 KB packets,
>>> center BER would need to go to 10^-13 to maintain the same
>>> packet loss rate. I'm not sure how much effect this would have
>>> practice, as most gigabit links achieve much better than 10^-12,
>>> work at all. Anyway, these items are ripe for debate and
>>**** end of message ****