Cisco Unified 7905G, Руководство администратора

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GL-7
Cisco IP Phone Models 7905G and 7912G Administrator Guide (SIP)
OL-4277-01
Glossary
N
NAT
Network Address Translation. Mechanism for reducing the need for globally
unique IP addresses. NAT allows an organization with addresses that are not
globally unique to connect to the Internet by translating those addresses into
address space with global routing. Also known as Network Address Translator.
NTP
Network Time Protocol. Protocol built on top of TCP that ensures accurate local
time-keeping with reference to radio and atomic clocks located on the Internet.
This protocol is capable of synchronizing distributed clocks within milliseconds
over long time periods.
P
POTS
Plain Old Telephone Service. Basic telephone service that supplies standard
single-line telephones, telephone lines, and access to the PSTN.
proxy server
An intermediary program that acts as both a server and a client for the purpose
of making requests on behalf of other clients. Requests are serviced internally or
by passing them on, possibly after translation, to other servers. A proxy
interprets and, if necessary, rewrites a request message before forwarding it.
PSTN
Public Switched Telephone Network. PSTN refers to the local telephone
company.
Q
QoS
Quality of service. The ability of a network, whether the network is a complex
network, small corporate network, Internet service provider (ISP), or enterprise
network, to provide better service to selected network traffic over various
technologies, including Frame Relay, ATM, Ethernet and 802.1 networks, and
SONET, as well as IP-routed networks that may use any or all of these
underlying technologies.