Secure Computing sidewinder, Startup Manual

Page: 61 / 68

Glossary
49
mail server A network computer that serves as an intermediate station for electronic mail
transfers.
MAT (multiple address
translation) The ability for a single interface to support multiple external IP addresses so
that inbound connections can be directed based on IP addresses and service.
man page Short for manual page, refers to the online help that is available within the
UNIX operating system. For example, entering
man ls
at the UNIX prompt
displays a description of the UNIX
ls
command.
MX (mail exchanger)
records DNS entries that define where e-mail addresses within domain names get
delivered.
name server A network computer that maintains a relationship between IP addresses and
corresponding domain names.
NAS (network access
server) A system that provides dial-up connectivity to your IP network from a bank of
dial-up modems.
NAT (network address
translation) Changing the source address of a packet to a new IP address specified by the
administrator.
NIC (network interface
card) Hardware, like a computer circuit board, that contains a port or jack that
enables a computer to connect to network wiring (ethernet cable, phone line,
etc.).
operational kernel The Sidewinder SecureOS
™
kernel that provides the normal operating state,
including Type Enforcement controls. When this kernel is running, the
Sidewinder
appliance can connect to both the Internet and the internal
network, and all configured services are operational.
ping A command that sends an ICMP message from one host to another host over
a network to test connectivity and packet loss.
port The number that identifies the destination application process for transmitted
data. Port numbers range from 1 to 65535. (For example, Telnet typically uses
port 23, DNS uses 53, etc.)
primary name server The DNS server for a domain where the name information is stored and
maintained.
protocol A shorter term for communications protocol; provides a formal set of rules for
sending and receiving data on a communication line. TCP and UDP are
examples of protocols.
proxy A software agent on a Sidewinder appliance that acts on behalf of a user
requesting a network connection through the
appliance
. A proxy accepts a
connection from a user, make a decision as to whether or not the user or client
IP address is permitted to use the proxy, optionally does additional
authentication, and then completes a connection on behalf of the user to a
remote destination.