# Thread: Is it my cantennas or distance causing a slow link?

1. ## Is it my cantennas or distance causing a slow link?

I have two U.S. Robotics 54g’s set up in a bridge mode, no encryption. Using two cantennas built to EXACT specs for channel 6. The two cantennas are about 500 feet apart and I lined them up with a gun sighting laser at night, so I know they are pointing straight at each other.

Never any real bad problems over the two years they have been connected, just the speed has been nagging me for a while since they are supposed to be connected at 125Mbps (yeah right) but my internet speed is slower.

Any ideas?

2. i download ta about 19000kbs from my wired desktop, the pc connected to the 54g on channel 6 directly a floor below me cpas out at

so it might just be a 54g limitation.

3. The wifi router is 54 Mb. Add a bridge & it's cut in half.

4. Originally Posted by TonyT
The wifi router is 54 Mb. Add a bridge & it's cut in half.
I wasn't aware of that, but even at half speed why is it cutting down on downloading speeds?

Latency isn't high. I can ping the router through the wireless and get an average of 1ms.

C:\>ping 192.168.100.8

Pinging 192.168.100.8 with 32 bytes of data:

Reply from 192.168.100.8: bytes=32 time=1ms TTL=150
Reply from 192.168.100.8: bytes=32 time=1ms TTL=150
Reply from 192.168.100.8: bytes=32 time=1ms TTL=150
Reply from 192.168.100.8: bytes=32 time=1ms TTL=150

Ping statistics for 192.168.100.8:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 1ms, Maximum = 1ms, Average = 1ms

5. I just tried to ping while downloading a file, through the wireless, at about 400kb a second. Latency is not really that much higher.

C:\>ping 192.168.100.8

Pinging 192.168.100.8 with 32 bytes of data:

Reply from 192.168.100.8: bytes=32 time=1ms TTL=150
Reply from 192.168.100.8: bytes=32 time=2ms TTL=150
Reply from 192.168.100.8: bytes=32 time=10ms TTL=150
Reply from 192.168.100.8: bytes=32 time=4ms TTL=150

Ping statistics for 192.168.100.8:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 1ms, Maximum = 10ms, Average = 4ms

C:\>ping 192.168.100.8

Pinging 192.168.100.8 with 32 bytes of data:

Reply from 192.168.100.8: bytes=32 time=7ms TTL=150
Reply from 192.168.100.8: bytes=32 time=1ms TTL=150
Reply from 192.168.100.8: bytes=32 time=1ms TTL=150
Reply from 192.168.100.8: bytes=32 time=1ms TTL=150

Ping statistics for 192.168.100.8:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 1ms, Maximum = 7ms, Average = 2ms

C:\>ping 192.168.100.8

Pinging 192.168.100.8 with 32 bytes of data:

Reply from 192.168.100.8: bytes=32 time=1ms TTL=150
Reply from 192.168.100.8: bytes=32 time=1ms TTL=150
Reply from 192.168.100.8: bytes=32 time=4ms TTL=150
Reply from 192.168.100.8: bytes=32 time=1ms TTL=150

Ping statistics for 192.168.100.8:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 1ms, Maximum = 4ms, Average = 1ms

6. To clarify, it's not really reduced by 50%. Depending on how the devices are configured, and on what devices are used (bridges, repeaters, amps, additional aps), the throughput generally is reduced somewhat proportionally when adding additional devices in the chain from the comp back to the router. 80211g states 54 Mbps, but that's just fairy tale marketing hype, the max on 80211g is 24.7Mbps due to overhead. Add in lost packets, interference & it will get worse.
Wifi Throughput: