ho provato con questo rwin...va bene??
adsl tiscali 4 mega flat, xpsp2.
grazie,ciao
MTU = 1492
MTU is optimized for PPoE DSL broadband. If not, consider raising MTU to 1500 for optimal throughput.
MSS = 1452
MSS is optimized for PPPoE DSL broadband. If not, consider raising your MTU value.
Default TCP Receive Window (RWIN) = 127776
RWIN Scaling (RFC1323) = 1 bits (scale factor of 2)
Unscaled TCP Receive Window = 63888
RWIN is a multiple of MSS
Other RWIN values that might work well with your current MTU/MSS:
511104 (MSS x 44 * scale factor of 8)
255552 (MSS x 44 * scale factor of 4)
127776 (MSS x 44 * scale factor of 2) <-- current value
63888 (MSS x 44)

