Workshop

A value denoting a collection of users. This concept is used in network file permissions. All users
belonging to a particular group share similar access privileges.
groupware
Application programs that are designed to make full use of a network. They often promote
collaborative work.
hacker
Someone interested in operating systems, software, security, and the Internet in general. This is
the original (and correct) definition from the good old days when hackers were the good guys.
Also called a programmer.
hardware address
The fixed physical address of a network adapter. Hardware addresses are just about always hardcoded
into the network adapter.
hole
See vulnerability.
host
A computer that offers services to users, especially on a TCP/IP network. Also refers to older
mainframe computers.
host table
Any record of matching hostnames and network addresses. These tables are used to identify the
name and location of each host on your network. Such tables are consulted before data is
transmitted. (Think of a host table as a personal phonebook of machine addresses.)
HP/UX
A flavor of UNIX from Hewlett Packard.
hub
A hardware device that allows the sharing of a network segment by repeating signals between
ports. (Like the spokes of a wheel, a hub allows many network wires to converge at one point.)
hypertext
A text display format commonly used on Web pages. Hypertext is distinct from regular text
because it’s interactive. In a hypertext document, when you click or choose any highlighted word,
other associated text appears. This allows for powerful cross-referencing and permits users to
navigate an entire set of documents easily.
Hypertext Markup Language (HTML)
The formatting commands and rules that define a hypertext document. Web pages are written in
the HTML format.
Hypertext Transfer Protocol (HTTP)
The protocol used to traffic hypertext across the Internet. It’s also the underlying protocol of the
WWW.
IDEA
See International Data Encryption Algorithm.
Identification Protocol (IDENT)
A TCP-based protocol for identifying users. IDENT is a more modern, advanced version of the
Authentication Protocol. You can find out more about IDENT by obtaining RFC 1413.
IGMP