TCP segments usage

Command: sar -n TCP

      iseg/s
	     The  total  number  of  segments  received  per  second,
	     including  those  received  in  error [tcpInSegs].  This
	     count includes segments  received  on  currently  estab-
	     lished connections.

      oseg/s
	     The  total number of segments sent per second, including
	     those on current connections but  excluding  those  con-
	     taining only retransmitted octets [tcpOutSegs].