Product guide

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Acronyms
VoIP: Voice over Internet Protocol
FXO: Foreign eXchange Office interface is the port that receives the analog line.
FXS: Foreign eXchange Subscriber interface is the port that actually delivers the analog line to
the subscriber.
SIP: Session Initiation Protocol, SIP is a signalling protocol used for establishing sessions in an IP
network.
IAX: Inter-Asterisk Exchange Protocol, is a communications protocol for setting up interactive
user sessions. IAX is similar to SIP.
RTP: Real-Time Transport Protocol, RTP is used to encapsulate VoIP data packets inside UDP
packets. RTP provides end-to-end network transport functions suitable for applications
transmitting real-time data, such as audio, video or simulation data, over multicast or unicast
network services.
UDP: User Datagram Protocol, UDP is a communications protocol that offers a limited amount of
service when messages are exchanged between computers in a network that uses the Internet
Protocol (IP).
TCP: Transmission Control Protocol , TCP is a set of rules (protocol) used along with the Internet
Protocol (IP) to send data in the form of message units between computers over the Internet.
SMTP: Simple Mail Transfer Protocol, SMTP is the de facto standard for electronic mail transport
across the Internet.
TOS: Terms of service, the “ToS” or “TOS” are rules by which one must agree to abide by in
order to use a service. Unless in violation of consumer protection laws, such terms are usually
legally binding.
DTMF: Dual-tone multi-frequency, DTMF signaling is used for telephone signaling over the line
in the voice-frequency band to the call switching center. The version of DTMF used for telephone
tone dialing is known by the trademarked term Touch-Tone, and is standardised by ITU-T
Recommendation Q.23. Other multi-frequency systems are used for signaling internal to the
telephone network.
DHCP: Dynamic Host Configuration Protocol, DHCP is an auto configuration protocol used on
IP networks. DHCP allows a computer to be configured automatically, eliminating the need for
intervention by a network administrator. It also provides a central database for keeping track of
computers that have been connected to the network. This prevents two computers from
accidentally being configured with the same IP address.
NTP: Network Time Procotol, NTP is a protocol for synchronizing the clocks of computer
systems over packet-switched, variable-latency data networks. It is designed particularly to resist
the effects of variable latency by using a jitter buffer.
Vlan: Virtual Local Area Network, is a group of hosts with a common set of requirements that
communicate as if they were attached to the same broadcast domain, regardless of their physical
location. A VLAN has the same attributes as a physical LAN, but it allows for end stations to be
grouped together even if they are not located on the same network switch. Network
reconfiguration can be done through software instead of physically relocating devices.