LCA 2011 is scheduled to be held in Brisbane from January 24 to 29 next year.
Allman's contribution is a foundation element of the internet; for years, Sendmail was the only MTA used to carry mail on the internet, the staple form of digital communication for many years.
Allman was one of the original hackers who were creating extensions to the BSD code and one of those was delivermail which was later known as Sendmail. It shipped with BSD 4.1c in 1983, the first BSD version that included TCP/IP protocols.
Allman has won numerous awards for his contribution and in 2009 was recognised as distinguished engineer by the Association for Computing Machinery.
More recently, there have been other MTAs developed, like Wietse Venema's Postfix, Phillip Hazel's Exim and Dan Bernstein's Qmail. Many old-timers, however, still prefer Sendmail which is still the most widely used MTA on UNIX systems and UNIX clones.
Allman is the second keynote speaker to be confirmed, with the LCA 2011 organisers announcing that inventor, writer, educator and broadcaster, Mark Pesce, would be presenting at the conference.
Pesce is a co-inventor of the Virtual Reality Markup Language (VRML) which forms a basis for 3D rendering and is used by millions.