Ultra 2 Plus (just got it early this week) Usage is file transfer for a small business: Word, CAD files, ARGIS Files, JPGs, PNGs, TIFFS, Excel files, Powerpoint files, Quickbooks files. File back-up for several PCs DLNA Streaming server to a PS3
I'm uncertain if I should enable Jumbo Frames on my NAS, and then enable Jumbo Frames on the PCs connected to the NAS.
I have read there is some risk of fragmenting packets when using Jumbo Frames, so my questions are:
1) Is it worth the speed/lower CPU to utilize Jumbo Frames?
2) Is my Ultra 2 Plus NAS and higher end PCs powerful enough to offset sending the smaller packets back and forth?
3) Will I get an appreciable speed in file transfer for remote access, or only local file access?
4) If I enable Jumbo Frames, what sizes should I enable on my PC's ethernet chip?? I have many choices there. Just pick the biggest one available, or not necessarily?
5) Is the risk of corrupted data from using Jumbo Frames appreciable or remote?
------------- Denton Gentry on February 6, 2010 11:13 PM I participated in the IEEE 802.3 committee for a while. IEEE never standardized a larger frame size for two reasons that I know of:
1. The end stations can negotiate the frame size, but there was no backwards-compatible way to ensure that all L2 bridges between them can handle it. Even if you send a jumbo frame successfully, you can still run into a problem later if the network topology changes and your packets begin taking a different path through the network. 2. The CRC32 at the end of the packet becomes weaker after around 4 KBytes of data. It can no longer guarantee that single bit errors will be caught, and the multibit error detection becomes weaker as well.
One is free to enable it, and it does improve the performance, but the situation is unlikely to ever get better in terms of standard interoperability. It will always be an option to be enabled manually.
Also a number of years ago,. jumbo frames provided a much bigger boost. Going from 1.5K to 9K regularly doubled performance or more. What has happened since is smarter ethernet NICs: they routinely coalesce interrupts, steer packets from the same flow to the same CPU, and sometimes even reassemble the payload of the 1.5K frames back into larger units. The resistance to standardizing jumbo frames resulted in increased innovation elsewhere to compensate.
