RJ Atkinson wrote:
>
> At 16:15 29/06/00 , Joe Touch wrote:
>
> >DS appears to be better for large, flat spaces (largely 2-dimensional,
> >under 3 stories tall, since transcievers on the middle floor largely
> >cover the upper and lower).
> >
> >FH is better for more spherical spaces (largely 3-dimensional).
>
> These optimisations do not appear to matter significantly in practice
> in the locations that IETFs have been held or in other places where
> I have experience with DS/FH being overlaid (a work campus environment).
That is interesting - it was the deciding factor in the deployment here.
DS was not capable of covering the 3-D space sufficiently, due the the
number of overlapping cells required, and the number of "channels"
available.
> >And DS and FH do not play well together, i.e., it's much better to stay
> >away from concurrent overlapping installations. I had earlier measured a
> >BW penalty of between 1/2 to 3/4 (transferring data over only one of the
> >two technologies at a time, in a concurrent deployment).
>
> IETF/DC is a fine counter-example of why the above might theoretically
> be true,
See "measured" above. Theory was not involved. :-)
but is not really true in deployed networks. IETF/DC had both
> overlaid on the same 3D spaces and both worked OK. Obviously one
> must be thoughtful about the channel/frequency plan and such like
> (which is true regardless of overlaid networks).
Agreed.
Joe
