Internet’s behavior and its effect on Internet vulnerability is important for national security, communications within and among businesses, and the flow of e-mail and e-commerce.

The introduction of the Advanced Encryption Standard algorithm last year could assure that information encrypted by it and sent over the Internet cannot be decoded by anyone who intercepts it, at least for the next several decades. The challenge now is to ensure the security of the encryption process so that the specific information needed to decode messages remains known only to those who should know it. This is primarily an issue of people and policy. However, NIST is working on techniques called key-management protocols that will help enforce the security of the encryption and decoding process.

A major challenge, one that could have a significant impact on Internet reliability and speed from the user’s viewpoint, lies in resolving the so-called lastmile bottleneck. This is the connection between the desktop terminal and the Internet service provider. Technical advances in optical communications, some of them associated with developing Internet II, will shorten this last mile stretch by stretch, increase network communications, and perhaps even solve the bottleneck in the coming decade.

Imaging has served as a vital impetus to discovery across the spectrum of science for several centuries. This fact will remain true in the 21st century.

Advances in imaging at the nano- and molecular scales by various techniques have contributed significantly to the understanding and exploitation of materials and processes. As science seeks to understand and control nature at its smallest scales, the need for new and improved imaging techniques—more sensitive, more specific, sharper in detail—takes on new urgency. New approaches and refinements of old, reliable methods will certainly emerge in the coming decade. Femtosecond lasers, for example, are opening a new era of investigation, ranging from biochemical reactions to fundamental studies of quantum mechanics. Optical microscopy, the oldest of the imaging sciences, and imaging holography could find new uses. Improvement in synchrotron-radiation resolution promises sharper images of such things as chemical-bond orientation, individual magnetic domains, solid-state reactions, catalysts, and the surfaces of semiconductors.

Refinements in femtosecond imaging and its application to new areas promise greater understanding in a broad range of disciplines, from cell biology to materials science. The laser-based technique already has demonstrated, for example, that DNA is not a rigid molecule but is capable of considerable motion. Currently, laser pulses of 5 femtoseconds can be achieved. The discovery that