3com drums version 4.3 User Manual
Appendix D. Definitions of terms
AFS, Andrew File System
AFS is a more secure way of distributing file systems over a network. If files are mounted over the Internet,
AFS is fairly secure. Normally, AFS uses Kerberos for security management.
AFS is fairly secure. Normally, AFS uses Kerberos for security management.
ARP
ARP, Address Resolution Protocol, is a protocol for mapping an IP address to a physical machine address in
the local network. A thorough description of ARP can be found in RFC 826.
the local network. A thorough description of ARP can be found in RFC 826.
Client program
A client program is one that the user runs on her computer. A client program connects to a server. One example
of a client program is Netscape (a WWW client). One benefit of dividing up a service into server and client
programs is that the server program can be run on a larger computer with better resources, and the users do not
have to make their own copies of the databases. This allows the client programs to be run on less powerful
computers.
of a client program is Netscape (a WWW client). One benefit of dividing up a service into server and client
programs is that the server program can be run on a larger computer with better resources, and the users do not
have to make their own copies of the databases. This allows the client programs to be run on less powerful
computers.
Cracker
A person who breaks into computer systems and commits other criminal acts using a computer.
Daemon program
A daemon program is a server program for a service. This kind of program waits for and manages external
calls. A typical example is FTP. A user starts his FTP client. The client connects to the FTP server. Now the
user can transfer files to his own computer or to the server. See Server.
calls. A typical example is FTP. A user starts his FTP client. The client connects to the FTP server. Now the
user can transfer files to his own computer or to the server. See Server.
Denial of Service, DoS
A type of attack that tries to block a network service by overloading the server.
DHCP
DHCP, Dynamic Host Configuration Protocol, is a protocol for handing out IP addresses and other
configuration information to computers without having to log on to every single machine. Instead, the
computers themselves send out requests about this information at boot, and gets appropriate configuration
parameters from a DHCP server. A thorough description of DHCP can be found in RFC 2131.
configuration information to computers without having to log on to every single machine. Instead, the
computers themselves send out requests about this information at boot, and gets appropriate configuration
parameters from a DHCP server. A thorough description of DHCP can be found in RFC 2131.
DMZ
A DMZ is a computer network that is accessible from two other computer networks that have no direct contact
with each other. Often, one of these networks is the Internet and the other is a local, internal network. There is
no direct connection between the Internet and the local network, but both of them can access an intermediate
network, a demilitarized zone.
with each other. Often, one of these networks is the Internet and the other is a local, internal network. There is
no direct connection between the Internet and the local network, but both of them can access an intermediate
network, a demilitarized zone.
DMZs are often used for special servers, such as web servers, which must be accessible from two separate
networks.
networks.
DNS
Domain Name System; see Name servers.
Domain
A domain is a country, organization, or subdivision. All countries have one top domain for the country, except
for the USA, which is divided into a commercial domain (.com), a non-profit organizational domain (.org), a
university domain (.edu), a military domain (.mil), a governmental domain (.gov), and a network domain (.net).
All domains are hierarchical and each domain is responsible for the domains directly under it.
for the USA, which is divided into a commercial domain (.com), a non-profit organizational domain (.org), a
university domain (.edu), a military domain (.mil), a governmental domain (.gov), and a network domain (.net).
All domains are hierarchical and each domain is responsible for the domains directly under it.
A domain can have several sub-domains, which in turn can have sub-domains and so on. The structure
combines the domain name of the organization with the overlying domain name.
combines the domain name of the organization with the overlying domain name.
For example, Stanford University has the domain name stanford, which is under the university domain of
USA, .edu; together they form the domain stanford.edu. The university also has different departments under
stanford.edu.
USA, .edu; together they form the domain stanford.edu. The university also has different departments under
stanford.edu.
The departments of a company or organization can request a sub-domain from the domain manager. So if the
technicians in the company’s service division want their own domain, they can go to their domain manager and
technicians in the company’s service division want their own domain, they can go to their domain manager and
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