Received December 3, 2001
From: "Malin Gullstrand (ERA)" <Malin.Gullstrand@era.ericsson.se>

License statement IETF - TCP RXT Flag (draft-ludwig-tsvwg-tcp-rxt-flag)

PATENT LICENSE UNDERTAKING

In the TSV Working Group in the Internet Engineering Task Force (IETF), the proposal
"The TCP Retransmit (RXT) Flag" (http://search.ietf.org/internet-drafts/draft-ludwig-
tsvwg-tcp-rxt-flag-03.txt) dated November 2001 has been made by Reiner Ludwig and
Michael Meyer at Ericsson Research.

Said submission proposes the RXT method as defined by the text provided in Section 2,
Section 3, Section 4, and Section 5 of said submission. Telefonaktiebolaget LM
Ericsson owns the European patent application no. EP 01 127 446.1 that claims the thus defined
RXT method as such, and intends to file further patent applications in other countries
that claim the RXT method as such.

If said RXT method is included in an IETF standard, Ericsson is prepared to grant a
paid up, nonexclusive, royalty free license on any patent that might be granted for said
patent application no. EP 01 127 446.1 or one of the further patent applications claiming the
RXT method as such, to anyone without any restrictions.