Grandstream Networks GXW-410 User Manual page 36

MTU A Maximum Transmission Unit (MTU) is the largest size
bit bytes), that can be sent in a packet- or frame-based network such as the Inter
E thernet is 1500 byte.
N AT Network Address Translation
NTP Network Time Protocol, a protocol to exchange and synchronize time over networks The port used
is UDP 123 Grandstream products using NTP to get time from Internet
OBP/SBC Outbound Proxy or another name Session Border Controller. A device used in
OBP/SBCs are put into the signaling and media path between calling and called party. The OBP/SBC
acts as if it was the called VoIP phone and places a second call to the called party. The effect of this
behavior is that not only the signaling traffic, but also the media traffic (voice, video etc) crosses the
OBP/SBC. Without an OBP/SBC, the media traffic travels directly between the VoIP phones. Private
OBP/SBCs are used along with
Public VoIP service providers use OBP/SBCs to allow the use of VoIP protocols from private networks
with internet connections using NAT.
PPPoE Point-to-Point Protocol over Ethernet is a network protocol for encapsulating PPP frames in
Ethernet frames. It is used mainly with cable modem and DSL services.
PSTN Public Switched Telephone Network. The phone service we use for every ordinary phone call, or
called POT (Plain Old Telephone), or circuit switched network.
RTCP Real-time Tran sport Control Protocol, defined in
Transport Protocol (RTP), It partners RTP in the delivery and packaging of multimedia data, but does not
transport any data itself. It is used
m ultimedia session. The primary function of RTCP is to provide feedback on the quality of service being
provided by RTP.
R TP Real-time Transport Protocol defines a standardized packet format for delivering audio and video
over the Internet. It was developed by the Audio-Video Transport Working Group of the
published in 1996 as RFC 1889
SDP Session Description Protocol is a format for describing
has been published by the
SIP Session Initiation Protocol, An IP telephony signaling protocol developed by the IETF (RFC3261).
SIP is a text-based protocol suitable for integrated voice-data applications. SIP is designed for voice
tr ansmission and uses fewer resources and is considerably less complex than H.323. All Grandstream
products are SIP based
S TUN Simple Traversal of UDP over NATs is a
NATs) to find out its public address, the type of NAT it is behind and the internet side port associated by
the NAT with a particular local port. This information is used to
h osts that are both behind NAT routers. The protocol is defined in
with non-symmetric NAT routers.
TCP Transmission Control Protocol is one of the core protocols of the
applications on networked hosts can create connections to one another, over which they can exchange
data or packets. The protocol guarantees reliable and in-order delivery of sender to receiver data.
TFTP Trivial File Transfer Protocol, is a very simple
basic form of FTP; It uses
Grandstream Networks, Inc.
firewalls to enable VoIP calls to and from a protected enterprise network.
periodically to transmit control packets to participants in a streaming
IETF as RFC 2327.
network protocol
UDP (port 69) as its transport
GXW-410x User Manual
Firmware 1.0.0.53
packet or frame, specified in octets (eight-
RFC 3550 , a sister protocol of the
streaming media
allowing clients behind
set up UDP communication between two
RFC 3489 . STUN will usually work well
Internet protocol
file transfer protocol, with the functionality of a very
protocol.
net. The maximum for
VoIP networks.
Real-time
IETF and first
initialization parameters. It
NAT (or multiple
suite. Using TCP,
Page 36 of 37
Updated: 04/2007