Jane C. Blake
Managing Editor

This issue presents papers on diverse computing topics --- the Internet, modern Fortran language extensions for parallel computing, and performance measurement of AlphaServer 64-bit RISC systems --- each representing an area of engineering strength for Digital. Also in the issue is a thought-provoking paper on the preservation of historical computers.

The opening paper on the Internet Protocol version 6 examines the status of today’s Internet and looks toward its future. Digital is one of several companies participating in the working groups of the Internet Engineering Task Force on the transition to a new protocol. Dan Harrington, Jim Bound, Jack McCann, and Matt Thomas report what they have learned from designing an IPv6 prototype, and compare and contrast the new version with the existing protocol, IPv4. The most important difference between the versions --- one that will relieve the strain on the Internet --- is the increase in IPv6 of address size from 32 bits to 128 bits. The authors conclude with a look at future work in such areas as security and data link interfaces for ATM. 

Our next paper --- an unusual one not only for the issue but for this Journal --- temporarily moves the discussion from computing’s future to its past. Max Burnet and Bob Supnik argue that an understanding of computing’s past is vital to its future. The authors present two computer preservation techniques: restoration and simulation. To exemplify issues in restoration, they review the status of a project to restore a large UNIBUS-based PDP-11 system. The section on simulation describes the types and purposes of simulators and presents a case study of SIM, a simulator implemented in C for the study of historical computer architectures.

In a paper on modern Fortran, Bill Celmaster demonstrates that today’s Fortran is a viable mainstream language for parallel computing. Since its development more than 40 years ago, Fortran has been extended by language designers to meet the needs of users, particularly the needs of scientific/technical users who require mathematical expressivity and code optimization. Bill reviews key features of Fortran 90, recent efforts to standardize parallel extensions to Fortran, and shared-memory parallelism. He includes three case studies that illustrate the data parallel and single-program--multiple-data styles of programming.

Two papers describe testing methodologies that resulted in leadership system performance under the TPC-C benchmark for a cluster system and for a single-node system. The first paper presents the evaluation of an AlphaServer 8400 5/350 TruCluster configuration supporting the Oracle Parallel Server database. Judy Piantedosi, Archana Sathaye, and John Shakshober discuss the system tuning and the record-setting results of their work. The second paper, by Tareef Kawaf, John Shakshober, and Dave Stanley, looks at two optimization techniques --- locking intrinsics and OM profile-based optimization --- applied to a large database program running in the very large memory (VLM) environment on an AlphaServer 8400 system. The results of these optimizations are significant increases in throughput and database-cache hit ratios.

The development of AltaVista Forum is the subject of our final paper. Unlike other groupware products, AltaVista Forum uses the World Wide Web as infrastructure to facilitate the rapid development of collaboration applications for NT and UNIX systems. Dah Ming Chiu and Dave Griffin explain this design decision and share their experiences with usability studies, an interpretive language (Tcl) for building the tool kit, and the inclusion of an indexing and search engine.

The next issue of the Journal, volume 8 number 4, will feature the new AlphaServer 4100 high-performance midrange server system, a new implementation of MEMORY CHANNEL, and large-database technologies in the VLM environment.