Geekzone: technology news, blogs, forums
Guest
Welcome Guest.
You haven't logged in yet. If you don't have an account you can register now.


exportgoldman

1202 posts

Uber Geek

Trusted

#11713 7-Feb-2007 19:22
Send private message


Hello Everyone,

I have a client which is having issues very symptoms very similar to MTU packet size issues (unreliable browsing, Terminal Server sessions failing etc)

This client has a laptop and a 3G card, and sits out on a boat way past great barrier island. They can only get GPRS service, but has been working fine for the last year or so.

I setup my laptop to replicate their settings (Clean install of Windows XP) VMC 7.03.0004 (latest) and a 3G Card locked to GPRS with APN of web.vodafone.net.nz and internet.

Unusual results. I can ping 203.97.33.1 usually with up to a 1500 MTU from a broadband connection (Clear's DNS servers.)

From the GPRS connection I can only send a ping -f -l 64 and get a reply.

If I send a do not fragment and packet size of 65 and above it does not get a reply - BUT ALSO does not recieve a packet needs to be fragmented.

The maxmum packet I can sent with a fragmentation error is 1476, which seems right from what google says (but most dialup connections are 576 MTU)

My gateway when on Vodafone is 124.6.218.253 I can send packets of up to 1476, but they get eaten after this. Seems to be a GPRS problem, and perhaps even only on this gateway.

I called Vodafone Data support, but the only guy which knew had gone home for the day.

Questions - Whats the MTU meant to be for Vodafone GPRS??? Surely it isn't 64!!!




Tyler - Parnell Geek - iPhone 3G - Lenovo X301 - Kaseya - Great Western Steak House, these are some of my favourite things.

Create new topic
exportgoldman

1202 posts

Uber Geek

Trusted

  #60040 7-Feb-2007 19:48
Send private message


I dug a little deeper, I did a tracert and then pinged each host, some didn't respond, and the ones that did allowed 1765 sized packets all the way to what looks like the internet gateway 203.110.9.21 then simply dropped them, unless they were 64 bytes or under!

  1   577 ms   695 ms   683 ms  172.26.74.33 [myself]
  2   650 ms   581 ms   580 ms  172.26.65.1
  3   681 ms   576 ms   581 ms  172.26.65.124
  4   694 ms   599 ms   599 ms  172.26.65.188 [not pingable]
  5   501 ms   581 ms   737 ms  172.26.86.33 [not pingable]
  6   761 ms   719 ms   839 ms  172.26.86.1 [not pingable]
  7   594 ms   599 ms   737 ms  203.110.9.21
  8   772 ms   737 ms   719 ms  203.21.31.170




Tyler - Parnell Geek - iPhone 3G - Lenovo X301 - Kaseya - Great Western Steak House, these are some of my favourite things.

Create new topic





News and reviews »

Air New Zealand Starts AI adoption with OpenAI
Posted 24-Jul-2025 16:00


eero Pro 7 Review
Posted 23-Jul-2025 12:07


BeeStation Plus Review
Posted 21-Jul-2025 14:21


eero Unveils New Wi-Fi 7 Products in New Zealand
Posted 21-Jul-2025 00:01


WiZ Introduces HDMI Sync Box and other Light Devices
Posted 20-Jul-2025 17:32


RedShield Enhances DDoS and Bot Attack Protection
Posted 20-Jul-2025 17:26


Seagate Ships 30TB Drives
Posted 17-Jul-2025 11:24


Oclean AirPump A10 Water Flosser Review
Posted 13-Jul-2025 11:05


Samsung Galaxy Z Fold7: Raising the Bar for Smartphones
Posted 10-Jul-2025 02:01


Samsung Galaxy Z Flip7 Brings New Edge-To-Edge FlexWindow
Posted 10-Jul-2025 02:01


Epson Launches New AM-C550Z WorkForce Enterprise printer
Posted 9-Jul-2025 18:22


Samsung Releases Smart Monitor M9
Posted 9-Jul-2025 17:46


Nearly Half of Older Kiwis Still Write their Passwords on Paper
Posted 9-Jul-2025 08:42


D-Link 4G+ Cat6 Wi-Fi 6 DWR-933M Mobile Hotspot Review
Posted 1-Jul-2025 11:34


Oppo A5 Series Launches With New Levels of Durability
Posted 30-Jun-2025 10:15



Geekzone Live »

Try automatic live updates from Geekzone directly in your browser, without refreshing the page, with Geekzone Live now.



Are you subscribed to our RSS feed? You can download the latest headlines and summaries from our stories directly to your computer or smartphone by using a feed reader.