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D-Link Wireless Routers for Home and Small Business => Information => Archive => Topic started by: pbodq on February 06, 2009, 02:36:01 AM

Title: What is the maximum Jumbo Frame size that DIR 655 can accept?
Post by: pbodq on February 06, 2009, 02:36:01 AM

http://support.dlink.com/faq/view.asp?prod_id=3013&question=DIR-655
The FAQ said that it just supported up to 4KByte

However, I wonder whether it is outdated information

http://www.smallnetbuilder.com/content/view/30087/96/
The reviews dated 2007-07-09 said that it supports up to 9KByte

Does this statement apply to all hardware version?

My 655 is v1.21 A2 hardware and all my NIC can only support up to 4KByte.
Therefore, I cannot use them to have a 9KByte test on my 655.

Could anyone clarify this?
Title: Re: What is the maximum Jumbo Frame size that DIR 655 can accept?
Post by: Lycan on February 06, 2009, 08:41:30 AM
1) Jumbo frames are not intended for HOME networks. Doing this will degrade NAT performance, as the NAT will have more fragmenting to do.
2) The switch can handle 9K frames.
3) The NAT can only handle 4K frames.

In the end you will NOT see increased LAN performance by using jumbo frames, as the IPOS is designed to  handle a frame size of 1500.

Stay away from jumbo frames, it's intended for CORE network switches.

Title: Re: What is the maximum Jumbo Frame size that DIR 655 can accept?
Post by: tipstir on February 06, 2009, 11:27:12 AM
You can do jumbo frames but through Gig external switch what supports jumbo frames but you won't notice much gain in throughput in none domain enterprise environment.
Title: Re: What is the maximum Jumbo Frame size that DIR 655 can accept?
Post by: pbodq on February 08, 2009, 01:32:33 AM
1) Jumbo frames are not intended for HOME networks. Doing this will degrade NAT performance, as the NAT will have more fragmenting to do.
2) The switch can handle 9K frames.
3) The NAT can only handle 4K frames.

In the end you will NOT see increased LAN performance by using jumbo frames, as the IPOS is designed to  handle a frame size of 1500.

Stay away from jumbo frames, it's intended for CORE network switches.



thanks for yuor explanation.
Most of my traffic is in switching side such as Windows files sharing. I do not access the internet frequently.
Doesn't it worth to use JF?
Title: Re: What is the maximum Jumbo Frame size that DIR 655 can accept?
Post by: Lycan on February 09, 2009, 08:29:20 AM
Not really. You won't see any LAN transfer speed increases.


Title: Re: What is the maximum Jumbo Frame size that DIR 655 can accept?
Post by: mhoare1984 on March 18, 2009, 01:44:23 AM
Not really. You won't see any LAN transfer speed increases.

It depends, I have a DIR 655 with my DNS 323 and desktop PC all running 1Gbit and I have enabled Jumbo Frames at 9000 on both.

Since I transfer multi gigabyte files I got significantly better read performance from the DNS 323. Before enabling Jumbo Frames I was getting 12MB/s write and 15MB/s read. With 9000 Jumbo Frames enabled I'm getting 20MB/s write and 30MB/s read from my DNS 323. Also when a mate of mine brought his desktop PC around we were transferring at 60MB/s between our two desktop PCs so the DNS 323 must be bottlenecked at 30MB/s.

I must admit that small file transfers I saw absolutely no improvement. So it depends on what you transfer across your network and the speed of the source and destination, on whether or not you get better performance from enabling Jumbo Frames.
Title: Re: What is the maximum Jumbo Frame size that DIR 655 can accept?
Post by: lotacus on March 18, 2009, 04:50:12 AM
I read that the performance gain would be quite notible. One possible issue though is in a mixed envirobment. Same goes with switching capabilities. Not sure if the router falls back to the slowest link or queues the faster link when transfering data so that the slowest link has time to acknowledge requests and accept the data etc
Title: Re: What is the maximum Jumbo Frame size that DIR 655 can accept?
Post by: Lycan on March 18, 2009, 10:38:22 AM
I saw serious performance decreases in streaming environments with jumbo frames.

Title: Re: What is the maximum Jumbo Frame size that DIR 655 can accept?
Post by: ShMiCk on May 26, 2009, 12:10:00 AM
It depends, I have a DIR 655 with my DNS 323 and desktop PC all running 1Gbit and I have enabled Jumbo Frames at 9000 on both.

Since I transfer multi gigabyte files I got significantly better read performance from the DNS 323. Before enabling Jumbo Frames I was getting 12MB/s write and 15MB/s read. With 9000 Jumbo Frames enabled I'm getting 20MB/s write and 30MB/s read from my DNS 323. Also when a mate of mine brought his desktop PC around we were transferring at 60MB/s between our two desktop PCs so the DNS 323 must be bottlenecked at 30MB/s.

I must admit that small file transfers I saw absolutely no improvement. So it depends on what you transfer across your network and the speed of the source and destination, on whether or not you get better performance from enabling Jumbo Frames.

I got the same exact results as this user, same speeds and all. But I found that I got better results with Jumbo Frames set at 4k.