Packet loss?

[mks2005]

I'm on O2 ADSL broadband. I experience low pings (~20ms to UK servers) and great speed (always maxes my 16Mbit) at peak times. At first glance this would indicate a healthy internet connection, right?

I've been playing TF2 online for some time with no issue. Recently however, it's become almost unplayable due to lag/jerkiness. Now my ping is always low, and if I view the console in game it says I'm experiencing "choke", which as far as I am aware translates to packet loss?

Now I've run some ping.exe tests and if I ping bbc.co.uk for example, continually, I wont get any "request timed out" notifications, which was I associated to suffering from "packet loss", which I've had in the past with other ISPs at peak times. I suspect this is a very simplistic test however.

The other thing is, I seem to have this problem at all times of the day. Which to me indicates that it's perhaps not a generic ISP performance issue?

I'd appreciate any insight, particularily if there's anything I can do to test for packet loss and diagnose the problem in any other way. Do you think this definitely an ISP issue?

Thanks

 

[Alexrose1uk]

Something may have affected your rates; do any other games exhibit such issues.
I dug this quickly up from the valve forums as it may give you some insight into the cause.

Choke occurs when the server, factoring in your rate setting, determines that it can't send you an update yet because doing so would start to flood your connection.

The server will check back with every frame until you are ready to receive an update and send the update when your connection is ready, however, the server won't check the packet choke timer unless you have waited at least 1 / cl_updaterate seconds since the last update (i.e., if you are getting 20 updates a second, packets will be spaced at least 50 ms apart - this rate is also subject to the packet choke timer).

Also try adjusting your steam settings to reflect your current net speed ie change it to 56k, then back to appropriate/new appropriate choice. IIRC Steam will then auto adjust your rates for Valve games.

 

[Skidilliplop]

Simple ping won't accurately diagnose packet loss as it only sends tiny packets. Try some much bigger sizes with the ping -l <SizeInBytes> <target> switch. Most ISP networks and websites will respond to pings up to about 10000 bytes. Few will respond to greater than that due to DoS prevention measures.

Check your line stats for excessive errors. There are many factors other than your connection that could result in packet loss o UDP services.