Specifications

Appendix E - Glossary Ring
240
Mediatrix 4100
Ring
One of the two wires (the two are Tip and Ring) needed to set up a telephone connection. See Tip.
Router
A specialized switching device which allows customers to link different geographically dispersed local area
networks and computer systems. This is achieved even though it encompasses different types of traffic under
different protocols, creating a single, more efficient, enterprise-wide network.
Switched Circuit Network (SCN)
A communication network, such as the public switched telephone network (PSTN), in which any user may be
connected to any other user through the use of message, circuit, or packet switching and control devices.
Server
A computer or device on a network that works in conjunction with a client to perform some operation.
Session Description Protocol (SDP)
Describes multimedia sessions for the purpose of session announcement, session invitation and other forms
of multimedia session initiation. SDP communicates the existence of a session and conveys sufficient
information to enable participation in the session. SDP is described in RFC 2327.
Simple Network Management Protocol (SNMP)
A standard of network management that uses a common software agent to manage local and wide area
network equipment from different vendors; part of the Transmission Control Protocol / Internet Protocol (TCP/
IP) suite and defined in RFC 1157.
Simple Network Time Protocol (SNTP)
SNTP, which is an adaptation of the Network Time Protocol (NTP), is widely used to synchronize computer
clocks in the global Internet. It provides comprehensive mechanisms to access national time and frequency
dissemination services, organize the time-synchronization subnet and adjust the local clock in each
participating subnet peer. In most places of the Internet of today, NTP provides accuracies of 1-50 ms,
depending on the characteristics of the synchronization source and network paths.
Stack
A set of network protocol layers that work together. The OSI Reference Model that defines seven protocol
layers is often called a stack, as is the set of TCP/IP protocols that define communication over the Internet.
Subnet
An efficient means of splitting packets into two fields to separate packets for local destinations from packets
for remote destinations in TCP/IP networks.
T.38
An ITU-T Recommendation for Real-time fax over IP. T.38 addresses IP fax transmissions for IP-enabled fax
devices and fax gateways, defining the translation of T.30 fax signals and Internet Fax Protocols (IFP) packets.
Telephony
The science of translating sound into electrical signals, transmitting them, and then converting them back into
sound.
Tip
The first wire in a pair of telephones wire. The second wire is called the “ring” wire. The tip is the conductor in
a telephone pair cable which is usually connected to the positive side of a battery at the telephone company’s
central office. It is the telephone industry’s equivalent of Ground in a normal electrical circuit. See also Ring.