user manual

GXV-3000 User Manual Grandstream Networks, Inc.
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OBP/SBC
Outbound Proxy or another name Session Border Controller. A device used in VoIP networks.
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 firewalls to enable
VoIP calls to and from a protected enterprise network. 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
i.e. the phone service we use for every ordinary phone call, or called POT (Plain Old
Telephone), or circuit switched network.
RTCP
Real-time Transport Control Protocol, defined in RFC 3550
, a sister protocol of the Real-time
Transport Protocol (RTP), It partners RTP in the delivery and packaging of multimedia data,
but does not transport any data itself. It is used periodically to transmit control packets to
participants in a streaming multimedia session. The primary function of RTCP is to provide
feedback on the quality of service being provided by RTP.
RTP
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
IETF
and first published in 1996 as RFC 1889
SDP
Session Description Protocol, is a format for describing streaming media initialization
parameters. It has been published by the IETF as RFC 2327.
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 transmission and uses fewer resources and is considerably less complex than
H.323.
All Grandstream products are SIP based
STUN