Els valors possibles estan al rang de
NOTA: 65535: És 2 elevat a la 16 menys 1. És la mida màxima d'un paquet IPv4 està limitada a aquest valor ja que el camp de la capçalera IP que indica la mida del paquet té 16 bits
Valor per defecte (TCP receive window size):
A la majoria de versions de Windows (versions superiors a Windows NT i Millennium).
Microsoft document said TCP window size is 64 Kbytes, but based on 16bit of TCP window field at TCP header, maximum TCP window size would be 2^16 -1 = 65535 bytes=65 Kbytes(the maximum unscaled window size). As you know TCP/IP was born in 1969 and it was designed and developed on WAN and LAN speed at that time. Most common Ethernet protocols were 10based-5, 10base-2 and later 10based-T. Yes, still we are using same TCP / IP header. It's kinds of old for these days fast network environment. Even my home network is based on GigE ports. Most of the networks are 100 times faster than when TCP was developed. Well, WAN speed is not being moved fast than LAN. Still many people are using enhanced 56K modem links, T1s and below 3Mbps broadband link (of course upload is much slower than download). Then what is adequate TCP receive window size? For fast LAN and slow WAN.