==
nit --

The Item can be used in a neighbor specific message if the radio use
   dedicated subcarriers to talk to neighbors.

use/uses

==
nit --

Frequency selection is often controlled by the radios configuration.

radios/radio's

==
question --

This might not apply here, but should it be possible to extend the signaling here to things like spread spectrum channels?

==
question --

   Request Link Characteristics message) be used to change the frequency
   of the radio in a standardized way.
   
This would seem to inlude frequency hopping support (?). Would there be any timing limits on how often a radio could swap channels (there may be timing limits later in the doc I've not hit yet)?

==
nit -- 

The format of the Radio Band Data Item is:

   0                   1                   2                   3
   0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Data Item Type                | Length                        |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                       Carrier Frequency                       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                       Carrier Frequency                       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                           Bandwidth                           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                           Bandwidth                           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Flags     |
   +-+-+-+-+-+-+-+-+
   
I find this format a little confusing, as it could indicate two different carrier frequency fields (?): I think a possibly easier to understand format might be something like:

The format of the Radio Band Data Item is:

   0                   1                   2                   3
   0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Data Item Type                | Length                        |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                       Carrier Frequency                       |
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                           Bandwidth                           |
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Flags     |
   +-+-+-+-+-+-+-+-+

==
question --

The length of the Radio Bnd Data Item is set to 17. If this won't ever change (and the packet format seem to be set up to support fixed length values), does the length need to be included? Could the Flags field be moved to where the length is?