Timing advance handling is in RSL and thus independent of the BTS you use.
OpenBSC does it for all the BTS it supports. 

However, I am not sure the ip.access nanoBTS hardware/firmware actually
implements it on the radio layer, considering it is intended as a
pico/microcell.

--
- Harald Welte <laforge@gnumonks.org>           http://laforge.gnumonks.org/
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