Well it’s official, CableNut is the ONLY internet connection tweaking application that will allow you to optimize your internet connection with Windows XP SP2. SP2 makes numerous changes to your registry one of them is your TCP and AFD values, the ones that control your internet bandwidth. CableNut is the ONLY application that allows you to optimize your AFD (Ancillary Function Device – it acts as an entry point for Winsock functions to get to TCPIP.sys). For years the CableNut Team has been saying how important the AFD registry values are and how they help optimize your bandwidth but many others (DSLR cough, cough, wink, wink) have argued that they don’t effect anything.
With the release of Windows XP SP2 the updated TCP/IP stack now redirects to your AFD values in the registry. Try a TCP/IP Analyzer test or DSLR Tweak Test and see, it will show your RWIN (DefaultReceiveWindow) as the value you have in CableNut under DefaultReceiveWindow which is an AFD parameter. This shows how important it is to use CableNut so you can fully optimize connections bandwidth.
We, the CableNut Team, are proud to be the first to publicly announce this. We are still looking into what exact changes are made to the TCP/IP stack.
