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GA90 Modular Gateway User’s Manual
or changes to an RFC are permitted once it becomes an Internet standard. changes to internet
standards are enacted through subsequent RFCs that supersede or elaborate on all or parts of
existing RFCs.
Reverse Address Resolution Protocol (RARP).
A protocol by which a physical machine in a local
area network can request its IP address from a gateway server’s Address Resolution Protocol table
or cache. RARP is described in RFC 903.
RJ-45.
A single-line digital transmission interface. Resembling a standard phone connector, an
RJ-45 connector is twice as wide (with eight wires) and is used for connecting computers to local
area networks (LANs) or phones with multiple lines.
Router.
A device that determines the next network point to which a data packet should be sent on
the to its final destination. Routers also act as traffic cops, allowing only authorized machines to
transmit data into the local network so that private information can remain secure. In addition to
supporting these dial-in and leased connections, routers also handle errors, maintain network
usage statistics, and handle security issues.
Routing Information Protocol (RIP).
A widely used protocol for managing router information
within a self-contained network, such as a corporate LAN. A gateway host sends its entire routing
table to it closest neighbor every 30 seconds, which in turn passes the table to its neighbor. this
process is repeated until all hosts in the network have the same information. RIP is described by
RFC 1058.
Server.
A computer program or device that provides services to other computers.
Session Description Protocol (SDP).
An ASCII-based protocol that describes multimedia sessions
and their related scheduling information, including information transport session participant
port numbers and contact addresses. The ZIP 4x4 phone uses SDP for session descriptions as
documented in RFC 2327.
Session Initiated Protocol (SIP).
An Internet standard protocol that defines a method of initiating
an interactive user session involving multimedia elements, such as voice, chat, gaming, video,
and virtual reality. SIP is a request-response protocol that deals with requests from clients and
responses from servers through any transport protocol, such as UDP or TCP. Described by RFC
3261, SIP can establish, modify, or terminate multimedia sessions or Internet telephony calls.
Simple Network Management Protocol (SNMP).
The protocol that governs network management
and the monitoring of network devices and their functions. SNMP is described formally in RFC
1157 and in a number of related RFCs.
Simple Network Time Protocol (SNTP).
A protocol that synchronizes computer clocks on an IP
network. Similar to NTP with fewer features. Some IP phones use SNTP for their date and time
synchronization functions. Described by RFC 2030.
SIP Endpoint.
An internet host that understands the SIP protocol.
SIP Registrar.
A SIP Registrar is a UAS that responds to REGISTER requests and maintains a list
of bindings that are accessible to proxy servers and redirect servers within its administrative
domain.
SIP Server.
A network device that performs special functions at the request of SIP endpoints.
Servers typically act in response to SIP endpoint requests, but can also initiate functions on their
own. RFC 3261 defines three types of SIP servers: SIP Proxy servers, Redirect servers, and
Registrar servers.