As noted above one of the changes to the kernel will be that it has to recognise the existence of the new flag MSG_EOF.
T/TCP introduces three new options in the protocol [RFC1644] which will have to be implemented in the kernel. These are known as CC options and are used to administer the sending and receiving of segments, and the synchronisation of the two hosts. The three options are CC, CCnew and CCecho.
CC is discussed earlier on in section 5.2. CCnew only appears in the initial SYN segment of a connection, and is sent when the client needs to perform the normal 3-Way Handshake. CCecho can only appear in the second segment of a 3-Way Handshake. It echoes the client's CC or CCnew value and informs the client that the server understands T/TCP.
The kernel will also have to hold a cache for each client, as mentioned in section 5.2, with a number of variables. This cache is used in the TAO.