The Availability Digest is
published by Sombers Associates, Inc. We have been active in
mission-critical, high-availability solutions for over forty
The Managing Editor of the
Availability Digest is Dr. Bill Highleyman.
Having received his Doctorate of Electrical Engineering,
brings decades of experience in the design and implementation of
mission-critical computer systems. As Chairman
of Sombers Associates, he has been responsible for implementing
dozens of real-time mission-critical systems for companies
such as Amtrak, Dow Jones, Time, McGraw Hill, Tandem, Federal
Express, Chemical Bank, SIAC, Smith Kline, G. E. Credit,
Southeast Bank, Harris Satellite, A. C. Nielson, and Harris
He has published extensively on
availability, performance, testing, middleware, and other
technical topics. He is
the author of Performance Analysis of Transaction Processing
Systems, published by Prentice-Hall, and is co-author of the
three-volume series, Breaking the Availability Barrier.
These books are available at
Barnes and Noble.
Highleyman is co-inventor of "Method of
increasing system availability by splitting a system," U. S.
Patent No. 7,113,938;
"Asynchronous coordinated commit
replication and dual write with replication transmission and
locking of target database on updates only,"
U. S. Patent No. 7,177,866; and "Split
processing system for providing increased system availability,"
U. S. Patent No. 7,194,488.
He is also co-inventor on several other patents and patent applications in
the fields of continuous- and high-availability technologies.
He is past chairman of ITUG, the HP
NonStop Users' Group, and is active in presenting availability
seminars and providing availability consulting. Dr. Highleyman
is also a sought-after technical writer and researcher on
a wide variety of technical subjects.
Highleyman can be contacted at