ADSL Asymmetric Digital Subscriber Line

FCC Federal Communications Commission

FXO Foreign Exchange Office.

FXS Foreign Exchange Station.

IETF Internet Engineering Task Force

IVR Interactive Voice Response.

MCU Multipoint Control Unit

MGC Media Gateway Controller.

MGCP Media Gateway Control Protocol.

MOS Mean Opinion Score.

MTU Maximum Transmission Unit.

NAT Network Address Translation.

PBX Private Branch Exchange.

PSTN: Public Switched Telephone Network

RADIUS Remote Access Dial-in User Service.

RFC Request for Comments.

RTP: Real Time Protocol

RSVP: ReSerVation Protocol

SIP Session Initiation Protocol.

SS7 Signaling System 7.

TOS: Type Of Service

VPN Virtual Private Network

VoIP: Voice over Internet Protocol

WFQ Weighted Fair Queueing.

LAN: Local Area Network

WAN: Wide Area Network

ISP: Internet Service Provider

QoS: Quality of Service