Appendix A: Glossary

DES Data Encryption Standard. A published encryption algorithm that uses a 56- bit symmetric key to encrypt data in 64-bit blocks. IPSec, the industry standard for VPNs, supports 3DES. For more information, see FIPS PUB 46-3 at http:// csrc.nist.gov/publications/fips/fips46-3/fips46-3.pdf.

DHCP Dynamic Host Configuration Protocol. A protocol that allows network administrators to set up a server to manage IP addresses, automatically assigning IP addresses to devices on the network. DHCP simplifies IP man- agement, eliminating the need to manually assign IP addresses to devices and then track those addresses. For more information, see RFC 2131 at http:// www.ietf.org/rfc/rfc2131.txt.

DHCP deployment A deployment method for networks that are not 802.1X compatible. In this method method, the NAC 800 is placed between a switch and a DHCP server and

intercepts DHCP requests from non-tested or non-compliant endpoints. See also DHCP quarantine method.

DHCP quarantine A quarantine method that gives non-compliant endpoints an IP address in a method quarantine subnet, where they have access only to remediation services.

digital certificate See certificate.

DNS Domain Name Server. A server that associates Internet domain names (such as www.abccompany.com) with their corresponding IP addresses. Also called Domain Name System or Domain Name Service, both of which refer to the protocol and not the physical server.

domain In LDAP, a logical grouping of devices that allows the network administrator to manage all of the objects in a domain at the same time, for example, to control who has access to the objects in the domain.

domain controller A Microsoft Windows server that controls activities such as end-user access in a domain.

domain name See DNS. server

DSA Digital Signature Algorithm. A standard for digital signatures that is part of the DSS. For more information, see FIPS PUB 186-2 at http://csrc.nist.gov/ publications/fips/fips186-2/fips186-2-change1.pdf.

Dynamic Host See DHCP.Configuration

Protocol

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