TBF configuration

 # tc qdisc add dev ppp0 root tbf \ 
   rate 220kbit limit 3000 \ 
   burst 1500

Parameters:
dev ppp0 root tbf
add directly to ppp0, a token bucket filter
rate 220kbit
220kbit worth of tokens/second added
limit 3000 burst 1500
3000 bytes buffer, 1500 bytes in bucket max