Microsoft Patent Too Close to IPv6, Lawyers Say

Some open-source legal specialists charge that the software company's patent is invalid and draws on work previously done by the IETF.

Lawyers for the Public Patent Foundation and the Software Freedom Law Center are scrutinizing a patent held by Microsoft for which, one lawyer told, Microsoft failed to disclose prior work done by the Internet Engineering Task Force.

"This patent has been called to the attention of the free world, including the Public Patent Foundation," said Eben Moglen, a professor of law at Columbia University and a founding director of the Software Freedom Law Center, an organization that provides legal representation and other law-related services to protect and advance free and open-source software.

"We are aware that the patent should not have issued in view of the prior art available to the patent office but not cited by Microsoft in its application," Moglen said.

The patent in question, USP 6101499, filed in 1998 and issued in 2000, concerns automatic generation of IP addresses to facilitate simple network connections.

The technology described therein bears "more than a passing similarity" to IPv6, one of the backbones of the Internet, according to Frank Bernstein, a lawyer with Kenyon & Kenyon, a San Jose, Calif., firm. Bernstein represents a company—whose name he declined to disclose—that offers open-source products.

IPv6, short for Internet Protocol Version 6, is the next-generation protocol designed by the IETF to replace the current version of the Internet Protocol, IPv4. Most of the Internet now uses IPv4, which is nearing 20 years old. IPv6 addresses a number of problems in IPv4, such as a limited number of available addresses. IPv6 is expected to gradually replace IPv4 over the coming years.

Ironically, Microsoft Corp. on Tuesday boasted of a new integrated IPv4/IPv6 stack in its upcoming Longhorn operating system. Jawad Khaki, corporate vice president of Microsofts Networking and Devices Technologies division, painted a picture of the upcoming operating system that outlined Microsofts current Longhorn networking priorities, most of which centered around IPv6/IPv4. Specifically:

  • Delivery of a new, integrated IPv4/IPv6 stack optimized for low-speed wireless and multigigabit networks.
  • Enhancements to Redmonds support of core DHCP (Dynamic Host Configuration Protocol), RRAS/VPN and RADIUS networking infrastructure services, including updates allowing them all to fully support IPv6.

/zimages/3/28571.gifDo software patents stifle development? Click here to read Peter Coffees opinion.

Although chat participants in particular questioned IPv6 and wireless support during Microsofts presentation, "We will have complete support for IPv6 in Longhorn," said Henry Sanders, the general manager of Windows core networking. "All [network aware] components in Longhorn will support IPv6 addresses. We will have common UI [user interface] controls for IPv6 and support comparable to IPv4 for configuration."

IPv6 is also included in both Microsofts Windows XP operating system and in Linux.

Those familiar with the meetings of the IETF as the committee hammered out the IPv6 IP address discovery system told that Microsoft was actively participating in those discussions back in late 1997 and early 1998. Microsoft left the meetings and filed a patent for work on which there already existed numerous RFCs (requests for consensus)—basically the legislation that runs the Internet.

Next Page: Microsofts stance on patent reform could be convenient.