The Network Time Protocol (NTP) is used to synchronize the time of a computer client or server to another server or reference time source, such as a radio or satellite receiver or modem. It provides client accuracies typically within a millisecond on LANs and up to a few tens of milliseconds on WANs relative to a primary server synchronized to Coordinated Universal Time (UTC) via a Global Positioning Service (GPS) receiver, for example.
ZMailer is an internet message transfer agent. It is intended for gateways or mail servers or other large site environments that have extreme demands on the abilities of the mailer. It was motivated by the problems of the Sendmail design in such situations. It is intended and designed as a multi-protocol mailer. The only protocol supported in this distribution is RFC822 (and variations).
Dirvish creates a backup image of a directory tree using rsync. If there is already an older backup image, files which have not changed will be shared (hard-linked) between the two backups to save disk space. Where files have partially changed, rsync sends only the differences over the network. Each backup image is a complete copy of the original directory and can be used independently for restores, or deleted without affecting the other images.
BLAST is a set of similarity search programs designed to explore all of the available sequence databases regardless of whether the query is protein or DNA. It uses a heuristic algorithm which seeks local as opposed to global alignments, and is therefore able to detect relationships among sequences which share only isolated regions of similarity. It can be run locally as a full executable, and can be used to run BLAST searches against private, local databases, or downloaded copies of the NCBI databases. It runs on Mac OS, Win32, LINUX, Solaris, IBM AIX, SGI, Compaq OSF, and HP- UX systems.