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MOCET IP3022 SOHO IP Deskphone User Guide
RTP/RTCP
Real-Time
Protocol/Real-Time Control Protocol(RTP / RTCP) : IETF
specifications for audio and video signal management. Allows
applications to synchronize and spool audio and video information.
RTP (Real Time Protocol) is specifically concerned with the
dependable transmission of latency-sensitive traffic across the
network and is involved in using time stamping to determine network
jitter tolerance and makes sure that voice packets are arriving in
order.
SIP
Session Initiation Protocol: A protocol that provides telephony
services similar to H.323, but is less complex and uses less
resources. SIP (Session Initiation Protocol) is a signaling protocol for
Internet conferencing, telephony, presence, events notification and
instant messaging. SIP is a text-based protocol, similar to HTTP and
SMTP, for initiating interactive communication sessions between
users.
Subnetwork or
Subnet
Found in larger networks, these smaller networks are used to
simplify addressing between numerous computers. Subnets connect
to the central network through a router, hub or gateway. Each
individual wireless LAN will probably use the same subnet for all the
local computers it talks to.
TCP/IP
Internet Standard Protocol: The underlying technology behind the
Internet and communications between computers in a network. The
first part, TCP, is the transport part, which matches the size of the
messages on either end and guarantees that the correct message
has been received. The IP part is the user's computer address on a
network. Every computer in a TCP/IP network has its own IP
address that is either dynamically assigned at startup or
permanently assigned. All TCP/IP messages contain the address of
the destination network as well as the address of the destination
station. This enables TCP/IP messages to be transmitted to multiple
networks (subnets) within an organization or worldwide.
TOS
Type of Service: A method of setting precedence for a particular
type of traffic for QoS.
UDP
User Datagram Protocol. An unreliable networking layer that sits at
the same level of the networking stack at TCP. UDP is a
connectionless transport protocol that is part of a suite of protocols
(the others being RTP and IP) that allow for the timely and efficient
transfer of voice data across and IP network. UDP is the better
transport protocol for VoIP data than TCP.
VAD
Voice Activity Detection (VAD) helps save bandwidth during calls.
Examples: When you are making a VoIP call and you are not
speaking and you are listening, that silence is still taking up
bandwidth during the call. When silence is detected by VAD
software over a predetermined length of time, is sends silent
packets that inform other VAD enabled systems to stop holding the
bandwidth for these empty packets.