Petition to SOHO router makers...

[VirtualLarry]

Please only allow the selection of 1, 6, and 11 for channels for 2.4Ghz.

Far too often, I find routers set up on "in-between" channels, which in reality screw up routers set to the two overlapping channels.

For example, I found three routers in the neighborhood of one I was installing today. One was on Channel 6, one on 11, and one on, wait for it, channel *9*.

So of course I put the router I was installing on Channel 1.

 

[Jimmah]

I feel for you, when setting up my neighborhood LAN every single channel was in use. Felt a small part of my soul die that day.

 

[Ayah]

I feel for you, when setting up my neighborhood LAN every single channel was in use. Felt a small part of my soul die that day.

Networking is hard. Interestingly enough, in my apartment complex, only 1,6 and 11 are used to my amazement.

 

[theevilsharpie]

Those "in-between" devices aren't interfering with anything unless they're actually transmitting.

 

[imagoon]

I'll use 14 if I want to.

 

[VirtualLarry]

Those "in-between" devices aren't interfering with anything unless they're actually transmitting.

Which they are, automatically, at regular intervals. How do you think that you can see their SSID?

 

[theevilsharpie]

Which they are, automatically, at regular intervals. How do you think that you can see their SSID?

A typical Wifi beacon is around 40 bytes or so, and most systems will transmit them every 100 milliseconds. A beacon transmitting at a data rate of 2Mbps will take up 0.16% of the available bandwidth on the channel it's using. Put another way, a competing signal can transmit interference-free 99.84% of the time.

In other words, the bandwidth used by advertising the SSID is insignificant.

 

[Emulex]

you actually are allowed to use channel 12 and 13 now iirc. as long as the power range is very low. but alot of locked usa intel wifi chipsets refuse to use them. seems the laws have changed on power output and channels. if you are using channel bonding the obvious rules change.

 

[Gryz]

Put another way, a competing signal can transmit interference-free 99.84% of the time.

Just curious. When such interference happens, will the WiFi interface retransmit the frame ? Or will the frame be dropped, and does it expect the higher layer(s) to retransmit ? In the case of a collision on a sort of CDMA-network (like Ethernet), the interface will detect the collision and retransmit. I know nothing about WiFi, but it would be interesting to know if WiFi deals in a smart way with interference or not.

In other words, the bandwidth used by advertising the SSID is insignificant.

Last time I looked into TCP (which was over a decade ago), I read that the rule of thumb was this: 1% packet loss would result in a 50% throughput loss in TCP. This is because of the way TCP congestion control works. So even a 0.16% loss of packets because of interference might have a noticable effect on TCP performance (wild guess: 10-20%).