<P> To avoid fragmentation in the IP layer, a host must specify the maximum segment size as equal to the largest IP datagram that the host can handle minus the IP header size and TCP header sizes . Therefore, IPv4 hosts are required to be able to handle an MSS of 536 octets (= 576 - 20 - 20) and IPv6 hosts are required to be able to handle an MSS of 1220 octets (= 1280 - 40 - 20). </P> <P> Small MSS values will reduce or eliminate IP fragmentation, but will result in higher overhead . </P> <P> Each direction of data flow can use a different MSS . </P> <P> For most computer users, the MSS option is established by the operating system . </P>

Which of the following best defines tcp mss