Cisco – Avoiding WiFi interference between wireless ISP and our own Point-to-point bridge

No, that router should be pretty quick between computers on the network. I've never had that sort of issue using that firmware.

I would suggest starting with a fresh firmware install of DD-WRT without playing with any of the settings. Leave the network unprotected and test out the speeds. WPA can cause slowdowns if you have that enabled.

The other thing to look at is what kind of files you are transferring. Are they a large number of tiny files? That will considerably slow down the transfers.

Update: A few other things you can look for:

Wireless packet info on /Info.htm - This indicates how many packets are being sent/received and lost.

Try plugging the computers in (wired vs. wireless).

How is your load average (top right of the page) anything under 1 is OK.

On the /Status_Wireless.asp page, check to see what the actual signal strength is as reported by the router. This also gives you the Signal to Noise Ratio. I'm not sure what is good, but on mine the signal is at -88, noise -94, SNR 5. If you are getting bad signal, try changing the channel.

First I add that some of these replies need clarification.

There are two kinds of overlap, one is channel overlap where the frequencies overlap, and the second being signal overlap.

You MUST have signal overlap for all devices to have coverage in all areas, or even most devices in most areas.

Secondly, there are various schools of thought for frequency overlap and some manufacturers even suggest putting all APs on a common channel. In the case of roaming IP phones this case becomes even stronger as a phone may hop across APs while in a call. This of course depends much on the hardwae of the phones and antenna placement and design.

Let us assume that we had a large open area that we wanted wifi coverage in. Now lets take a pole and place it in the middle of the area. Now we place 4 directional 90 degree antennas on the pole, each 90 degrees from the other . In this situation one may make a strong case for having all APs on the same channel to facilitate roaming. In theory there is little signal overlap but all frequencies overlap.

Now we have an open area with walls on four sides. and place an AP on each of the four walls. The signals WILL overlap from each of the 90 degree antennas , so we may want to consider using separate non overlapping channels on each AP , however there are only 3 non overlapping channels. 1, 6 , and 11. So instead we do the best we can in North America this might be 1, 4, 7, and 11 , each AP having SOME necessary frequency overlap. Of course in a perfect world this might be better accomplished with three APS in a triangular configuration.

In my home I have toyed with APs on Same channel and separate channels and in the end I see little coverage difference., I do see however that some devices such as wireless IP phones can more easily hop to another AP while in a phone call. I see that in most areas I do not have more than 2 overlapping signals and each on channel 4 at present. As I sit here I can launch wifi seeker on my android and see either of the 2 available APs and even connect to either. This of course is easier to test with separate SSIDs but more practical to use common SSIDs fopr everyday use.