Checksum Arcanius

 Bad Comcast

 Good Comcast

Seen above are the same portion of two screen captures from two different games of Counterstrike. The info seen is the output of the function net_graph in the half life engine. As is normal, green means good, and red means bad. In fact, each red mark indicates a lost packet or a period of lost packets. Notice how many red marks there are in the Bad Comcast picture. Of course, that information is very anecdotal and doesn’t really isolate the problem – with just that information, you wouldn’t know if the problem were the counterstrike server, my router, my computer, the wireless link between them, or anything else. So I decided to roll in the big guns: the ping test.

I used the following command in four seperate command prompt windows:
ping -t -w 200 host
where
-t tells ping to ping until I tell it to stop
-w 200 tells ping to stop waiting at 200 ms and
host is either an IP adress or a hostname

Here are the results (grabbed by using control-break and copy/paste):

Ping statistics for 192.168.10.200: a computer on the same subnet, just one switch and two cat 5 cables away
Packets: Sent = 355, Received = 355, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 0ms, Maximum = 0ms, Average = 0ms

Ping statistics for 192.168.10.1: this is my router
Packets: Sent = 1239, Received = 1175, Lost = 64 (5% loss),
Approximate round trip times in milli-seconds:
Minimum = 2ms, Maximum = 49ms, Average = 3ms

Ok, so 5% loss is not ideal and I will try to make that better. I think I could get this to 0% with a little tweaking, but 5% packet loss hardly affects real world performace.

Ping statistics for 192.168.100.1: this is my cable modem
Packets: Sent = 1017, Received = 947, Lost = 70 (6% loss),
Approximate round trip times in milli-seconds:
Minimum = 4ms, Maximum = 31ms, Average = 5ms

This is on par with the 5% seen for the router, but the test started later and there are more lost packets, so there are definitely some packets lost between the router and the cable modem… how this is possible escapes me, since they are all of a foot apart with a nice cat5 cable in between. But still, 6% loss is not very noticeable in the real world.

Now it gets interesting:
Ping statistics for 24.18.144.1: this is my router’s default gateway
Packets: Sent = 1230, Received = 864, Lost = 366 (29% loss),
Approximate round trip times in milli-seconds:
Minimum = 10ms, Maximum = 480ms, Average = 63ms

All of my packets have to go through the default gateway, as this is my only path to the internet. And from here to there and back again (without touching the internet along the way), I loose almost 30% of my packets. This is all after my router, mind you, I have no control over anything at this point.

Now, for the real world test:
Ping statistics for 216.239.57.99: this is google.com
Packets: Sent = 1480, Received = 872, Lost = 608 (41% loss),
Approximate round trip times in milli-seconds:
Minimum = 31ms, Maximum = 489ms, Average = 84ms

Once we get out into the wild, nearly half of my packets never find their way home. And this is with no load whatsoever on the system.

“Pour sore misery down on me…” (I’m only happy when it rains)

Comments RSS 2.0 | Add a Comment | Trackback