Wireless Channel Bonding

802.11a/n supports Wireless Channel Bonding. Not to be confused with Dual band which indicates support for both 5GHZ spectrum (wireless a) and 2.4GHZ spectrum (wireless b/g/n). As the last post points out channels sets in 1, 6, and 11 in the 2.4GHZ n space each use about 20MHZ of spectrum each. My older RT-N15 WAP supports channel bonding using two adjacent channel sets (40MHZ). This is why in inssider we see a 5+9 and for our neighbors a 10+6. My newer RT-N66U dual band WAP also supports channel bonding but it seems to only use one channel set from the 2.4GHZ spectrum (at least according to inssider). From what I've read channel bonding works best when there is no interference and the 5GHZ address space is less crowded. This requires a nic with an a radio, dual band client wireless nics. None of my wireless nics on my laptops seem to connect in the 5GHZ space. In the Router Home Page we can see a channel bandwidth setting of 20MHZ or 20/40MHZ. The 20/40MHZ setting in the router web page enables channel bonding. In some cases Channel Bonding can even hurt performance, see here. Another thing to keep in mind is that connectivity in the 5GHZ address space has a much shorter range than the 2.4 GHZ address space, however it can transmit much more data when it works. It seems wireless channel bonding (40MHZ) can only be used with adjacent channels. We cannot for example combine one 20MHZ channel from 2.4 GHZ spectrum and one channel from 5 GHZ spectrum.