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MTU
A Maximum Transmission Unit (MTU) is the largest size packet or frame, specified in octets
eight-bit bytes), that can be sent in a packet- or frame-based network such as the Internet. The
maximum for Ethernet is 1500 byte.
NAT
Network Address Translation
NTP
Network Time Protocol, a protocol to exchange and synchronize time over networks, the port used is
UDP 123, allywll products using NTP to get time from Internet.
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 Caller. The
OBP/SBC acts as if it was the called VoIP phone and places a second call to the called Caller. 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. 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 Dinstar
products are SIP based
STUN
Simple Traversal of UDP over NATs is a network protocol allowing clients behind NAT (or multiple
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 set up UDP communication
between two hosts that are both behind NAT routers. The protocol is defined in RFC 3489. STUN will
usually work well with non-symmetric NAT routers.
TCP
Transmission Control Protocol is one of the core protocols of the Internet protocol suite. Using TCP,
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.