Re: MAE-EAST Moving? from Tysons corner to reston VA.
On Fri, 16 June 2000, "Richard A. Steenbergen" wrote:
In a public exchange point where you're talking to multiple networks across a shared media it makes sense to do GigE, multiple GigE, 10GigE, etc,
What is the largest MTU that you can use across a GigE fabric? --- Michael Dillon Phone: +44 (20) 7769 8489 Mobile: +44 (79) 7099 2658 Director of Product Engineering, GTS IP Services 151 Shaftesbury Ave. London WC2H 8AL UK
If I'm not mistaken, 9000bytes is the max.
From acenic.c (By D.Becker of course)
* To enable jumbo frames, simply specify an mtu between 1500 and 9000 * bytes to ifconfig. Jumbo frames can be enabled or disabled at any time * by running `ifconfig eth<X> mtu <MTU>' with <X> being the Ethernet * interface number and <MTU> being the MTU value. --- John Fraizer EnterZone, Inc On 16 Jun 2000 michael.dillon@gtsip.net wrote:
On Fri, 16 June 2000, "Richard A. Steenbergen" wrote:
In a public exchange point where you're talking to multiple networks across a shared media it makes sense to do GigE, multiple GigE, 10GigE, etc,
What is the largest MTU that you can use across a GigE fabric?
--- Michael Dillon Phone: +44 (20) 7769 8489 Mobile: +44 (79) 7099 2658 Director of Product Engineering, GTS IP Services 151 Shaftesbury Ave. London WC2H 8AL UK
the theoretical maximum (guaranteeing the same ber via crc-32) is 12k. 9k is a trade-off between this maximum and maximums of some applications (like nfs -- 8k). one of the first major jumbo frame pushers was alteon. -- dima.
-----Original Message----- From: owner-nanog@merit.edu [mailto:owner-nanog@merit.edu]On Behalf Of John Fraizer Sent: Friday, June 16, 2000 11:11 AM To: michael.dillon@gtsip.net Cc: nanog@merit.edu Subject: Re: MAE-EAST Moving? from Tysons corner to reston VA.
If I'm not mistaken, 9000bytes is the max.
From acenic.c (By D.Becker of course)
* To enable jumbo frames, simply specify an mtu between 1500 and 9000 * bytes to ifconfig. Jumbo frames can be enabled or disabled at any time * by running `ifconfig eth<X> mtu <MTU>' with <X> being the Ethernet * interface number and <MTU> being the MTU value.
--- John Fraizer EnterZone, Inc
On 16 Jun 2000 michael.dillon@gtsip.net wrote:
On Fri, 16 June 2000, "Richard A. Steenbergen" wrote:
In a public exchange point where you're talking to multiple
networks across a
shared media it makes sense to do GigE, multiple GigE, 10GigE, etc,
What is the largest MTU that you can use across a GigE fabric?
--- Michael Dillon Phone: +44 (20) 7769 8489 Mobile: +44 (79) 7099 2658 Director of Product Engineering, GTS IP Services 151 Shaftesbury Ave. London WC2H 8AL UK
On 16 Jun 2000 michael.dillon@gtsip.net wrote:
What is the largest MTU that you can use across a GigE fabric?
Frmo Extreme Networks manual: The jumbo_frame_mtu range is 1523 to 9216. The value describes the maximum size "on the wire," and includes 4 bytes of CRC plus another 4 bytes if 802.1Q tagging is being used. I'd be surprised if other vendors are much different. -- Mikael Abrahamsson email: swmike@swm.pp.se
I spoke with HP today. Their Procurve series switches support a maximum of 1522 bytes to include 802.1Q tagging. They wouldn't discuss if they planned to join the rest of the world in supporting jumbo frames on GigE. --- John Fraizer EnterZone, Inc On Fri, 16 Jun 2000, Mikael Abrahamsson wrote:
On 16 Jun 2000 michael.dillon@gtsip.net wrote:
What is the largest MTU that you can use across a GigE fabric?
Frmo Extreme Networks manual:
The jumbo_frame_mtu range is 1523 to 9216. The value describes the maximum size "on the wire," and includes 4 bytes of CRC plus another 4 bytes if 802.1Q tagging is being used.
I'd be surprised if other vendors are much different.
-- Mikael Abrahamsson email: swmike@swm.pp.se
participants (4)
-
Dmitri Krioukov -
John Fraizer -
michael.dillon＠gtsip.net -
Mikael Abrahamsson