Change Channels

Change Channels
Each AP broadcasts its signals over portions of the wireless frequencies
called channels. The 802.11b standard (the most common system as we
write) defines 11 channels in the United States that overlap considerably,
leaving only 3 channels that don’t overlap with each other. The IEEE 802.11a
standard specifies 12 (although most of today’s products only support 8)
non-overlapping channels. The 802.11g standard calls for the same 11 channels
in the United States as 802.11b, again with overlapping channels.
This affects your ability to have multiple access points in the same area,
whether your own or your neighbors’. Because channels can overlap, you
can have the resulting interference. For 802.11b access points that are within
range of each other, set them to different channels, five apart from each other
(such as 1, 6, and 11), to avoid inter-access point interference.
We discuss the channel assignments for wireless LANs like 802.11b further in
Chapter 6.