Glossary
GL-10
Cisco Router and Security Device Manager 2.5 User’s Guide
OL-4015-12
DMZ demilitarized zone. A DMZ is a buffer zone between the Internet, and your
private networks. It can be a public network typically used for Web, FTP and
E-Mail servers that are accessed by external clients on the Internet. Placing these
public access servers on a separate isolated network provides an extra measure
of security for your internal network.
DN Distinguished Name. A unique identifier for a Certification Authority customer,
included in each of that customer’s certificates received from that Certification
Authority. The DN typically includes the user’s common name, the name of that
user’s company or organization, the user’s two-letter country code, an e-mail
address used to contact the user, the user’s telephone number, the user’s
department number, and the city in which the user resides.
DNS Domain Name System (or Service). An Internet service that translates domain
names, which are composed of letters, into IP addresses, which are composed of
numbers.
domain name The familiar, easy-to-remember name of a host on the Internet that corresponds
to its IP address.
DPD dead peer detection. DPD determines if a peer is still active by sending periodic
keepalive messages to which the peer is supposed to respond. If the peer does
not respond within a specified amount of time, the connection is terminated.
DRAM dynamic random access memory. RAM that stores information in capacitors that
must be periodically refreshed.
DSCP Differentiated Services Code Point. DSCP markings can be used to classify
traffic for QoS. See also NBAR
DSLAM digital subscriber line access multiplexer.
DSS digital signature standard. Also called digital signature algorithm (DSA), the
DSS algorithm is part of many public-key standards for cryptographic
signatures.