Appendix A: Glossary

S

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-1Secure 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-management 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.

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