OID value: 1.3.6.1.2.1.6.1
OID description:
tcpRtoAlgorithm OBJECT-TYPE SYNTAX INTEGER { other(1), constant(2), rsre(3), vanj(4) } ACCESS read-only STATUS mandatory DESCRIPTION "The algorithm used to determine the timeout value used for retransmitting unacknowledged octets." ::= { tcp 1 }
See also the OID Repository website reference for 1.3.6.1.2.1.6.1