Security Solutions

A-20

Appendix A: Glossary

SA Security Association. Secure communication between two network devices

that is created from shared security information. A SA is used in IKE. For more

information, see RFC 4306 at http://tools.ietf.org/html/rfc4306.

SHA-1 Secure Hash Algorithm One. One of five cryptographic hash functions that

were designated by the National Security Agency. SHA-1 is used in TLS, SSL,

and IPsec and is considered to be a successor to MD5. For more information,

see RFC 3174 at http://tools.ietf.org/html/rfc3174.

shared secret Any authentication information such as a password that is “known” by two or

more network devices. The shared secret is identical on both devices.

SIM Subscriber Identity Module. A removable smart card that is used in mobile

phones to store the authentication credentials and other information for the

subscriber network.

smart card A credit-card sized plastic card that has integrated circuits embedded in it that

can process information. The card is either run through or placed near a

reader, which reads the data that is stored in the integrated circuits.

smart phone A cellular telephone that has Internet access capabilities.

SNMP Simple Network Management Protocol. An application-layer protocol that

supports the exchange of management information between network devices.

An SNMP network consists of agents, managed devices, and network-manage-

ment systems. Hierarchically organized information about network devices is

stored in and accessed from a MIB. The NAC 800 supports SNMPv2, which

controls access based on community. For example, a server that knows the

NAC 800’s read-only community name can read. For more information, see

RFC 1157 at http://www.ietf.org/rfc/rfc1157.txt.

spyware A broad category of malicious software designed to intercept or take partial

control of a computer’s operation without the informed consent of that

machine’s owner or legitimate user. While the term literally suggests software

that surreptitiously monitors the user’s actions, it has come to refer more

broadly to software that subverts the computer’s operation for the benefit of

a third party.

SSL Secure Sockets Layer. A protocol that was developed by Netscape for securing

the transmission of messages over the Internet. SSL works by using asymmetric

keys to encrypt message data. For more information, see http://

wp.netscape.com/eng/ssl3/draft302.txt.