D-Link Forums

The Graveyard - Products No Longer Supported => Routers / COVR => DIR-655 => Topic started by: alien on July 24, 2009, 03:22:11 AM

Title: MTU and firmware 1.32
Post by: alien on July 24, 2009, 03:22:11 AM

Since Firmware 1.32 i had to lower the mtu from 1500 to 1400 otherwhise i got an timeout with the download. And yes i use the american firmware. With firmware 1.21 and all others i didn't hav to do this.

Title: Re: MTU and firmware 1.32
Post by: Demonized on July 24, 2009, 03:29:14 AM

Download time outs can also be caused by the specific server hosting the package. Only if all of your connections suffer from disconnects there might be an issue with your MTU setting. So if that's not the case it's coincidence that setting it to 1400 solves a real issue.

Title: Re: MTU and firmware 1.32
Post by: alien on July 24, 2009, 04:31:50 AM

is trange then when i download from the same site before and the problem excist in firmware 1.32 and not below.

Title: Re: MTU and firmware 1.32
Post by: Demonized on July 24, 2009, 10:54:10 AM

Quote from: alien on July 24, 2009, 04:31:50 AM

is trange then when i download from the same site before and the problem excist in firmware 1.32 and not below.

It's your assumtion, since there's no way to check if it happens now with 1.2x firmware...

The reason why it is not DIR related is that your 655 connects to your internet modem, and the internet modem connects to the download site. And the modem usually has it's own settings so there is no 1-on-1 connection between the download site and your router, there's a modem in between. So trust me when I say that it is not a router issue.

You can ask your ISP what their MTU setting is with your subscription. For AOL DSL 1400 is the max MTU to use.

The most commonly used values:
    * 1500. The largest Ethernet packet size; it is also the default value. This is the typical setting for    non-PPPoE, non-VPN connections. The default value for routers, adapters and switches.
    * 1492. The size PPPoE prefers.
    * 1472. Maximum size to use for pinging. (Bigger packets are fragmented.)
    * 1468. The size DHCP prefers.
    * 1460. Usable by AOL if you don't have large email attachments, etc.
    * 1430. The size VPN and PPTP prefer.
    * 1400. Maximum size for AOL DSL.
    * 576. Typical value to connect to dial-up ISPs.

Title: Re: MTU and firmware 1.32
Post by: alien on July 25, 2009, 01:00:27 PM

i have cable

Title: Re: MTU and firmware 1.32
Post by: jpm67 on July 25, 2009, 01:42:40 PM

The best way to determine your maximum MTU is to use ping to determine the point at which packets become fragmented. This web site describes how.

http://www.dslreports.com/faq/5793 (http://www.dslreports.com/faq/5793)

Title: Re: MTU and firmware 1.32
Post by: KevTech on July 25, 2009, 03:13:59 PM

You can also go to SpeedGuide (http://www.speedguide.net/).

At the top click on Broadband, scroll down to Broadband Tools then click on SG TCP/IP Analyzer.

This will tell you what your setting are and if changes need to be made.

Title: Re: MTU and firmware 1.32
Post by: alien on July 26, 2009, 12:18:46 AM

Thanks, this topic can be closed