Glossary

A

 

AMA
Automatic Message Accounting.
APC
adjacent point code.
ASCII
American Standard Code for Information Interchange.

B
 
BAF
Bellcore AMA Format.
BAM
billing and measurements.
BAMS
Billing and Measurements Server. Performs CDR mediation and generates operational measurements derived from the call records. Converts the TLV (binary) CDRs produced on the PGW host to industry standard formats. More specifically, a standalone (simplex) or redundant pair of Sun host machines that Gateway TLV records via FTP from Cisco PGW nodes for post-processing into BAF output records using internal flat file tables and appropriate filtering, formatting, and CDR-to-BAF conversion routines.

C
 
CC
call control.
CDB
call detail block.
CDR
call detail record.
Cisco MGC software
Cisco Media Gateway Control (MGC) software. The generic name given to the Cisco software application that performs signaling and call control as well as the network functions expected from a PSTN switching point (SP). It terminates MTP3 and higher layers of the SS7/C7 protocol stack.
Cisco PGW 2200 PSTN Gateway
A collection of PGW hosts that collectively provide distributed call control (CC) and signaling services.
Cisco SLT
Cisco Signaling Link Terminal. An SLT provides physical connection to the SS7 network. It terminates MTP Layer 1 and 2 and backhauls MTP 3 and higher layers to the PGW hosts over the signaling (IP) network for call. Two or more SLTs are deployed in load-sharing mode.
CLEC
competitive local exchange carrier. Authorized by the Telecommunications Act of 1996, the creation of CLECs effectively constituted Phase II of the deregulation of the telecommunications market in the United States. Phase I was characterized by the divestiture of AT&T with the Judge Green decision of 1984. This decision led to the creation of the Baby Bells and enabled stronger competition in the long-distance market by MCI and Sprint. Phase II targeted the "local loop" and the Local Exchange Carriers (Bells and others) and led to the formation of startup companies with new investment capital. Some CLECs chose to resell excess capacity from the traditional carriers, others to create new plant, such as SONET ring fiber networks for business customers.
competitive local exchange carrier
See CLEC.

D
 
DPC
Destination Point Code.
DS0
digital service 0. A 64-kbps digital TDM channel used for carrying a single POTS call.
DS3
digital service 3. A 45-Mbps digital link.

E
 
EGR (egr)
egress: outgoing or terminating.
EMS
Element Management System. Provides element management for the Cisco PGW 2200. The Cisco Voice Services Provisioning Tool (Cisco VSPT) enables bulk provisioning and Cisco MGC Node Manager (Cisco MNM) provides fault and performance management.

F
 
FTP
File Transfer Protocol.

G
 
GW
gateway. See also MGW.

H
 
HSI
H.323 Signaling Interface. It enables the Cisco PGW 2200 (in Call Control mode) to act as an H.323 end point.

I
 
IAM
Initial Address Message
IC
Interexchange Carrier.
IGR (igr)
ingress: incoming or originating.
ILEC
incumbent local exchange carrier.
IMT
Inter-Machine Trunks.
IP
Internet Protocol.
IP mediation
A collection of Internet network usage records for billing purposes, such as real-time streaming video and voice/IP.
IP telephony
Telephony services provided over the Internet.
ISDN
Integrated Services Digital Network. ISDN services are gradually replacing POTS in affluent communities. Competing against ISDN are asynchronous digital subscriber lines and multiservice wireless applications.
ISP
Internet service provider.

L
 
LAN
local-area network.
LAN switch
Provides IP connectivity between all the elements of the signaling network. This signaling network is also referred to as the Control Signaling Network.
LERG
local exchange routing guide.

M
 
Man Machine Language
See MML.
media gateway
See MGW.
Media Gateway Control Protocol
See MGCP.
MGC software
Media Gateway Controller software. A generic term used for the Cisco PGW 2200 PSTN Gateway software when both call control and signaling applications apply.
MGCP
Media Gateway Control Protocol. A protocol based on a merging of the IPDC and SGCP protocols.
MGH
media gateway host. A device that physically contains the media gateway (that is, MGX is a media gateway host, VISM is the corresponding media gateway). MGH and MG are sometimes used interchangeably, depending on the context and device being referenced.
MGW
media gateway. A generic term used for the gateway between a QoS packet network and the PSTN/ISDN. There are three types of gateways: the trunking gateway, the access gateway, and the network access server or nonvoice gateway. Media gateways are termination points for the Media Gateway Control Protocol. Media gateways terminate MGCP links.
MML
The Man Machine Language used in a Cisco MGC software.

N
 
NAS
network access server.
NNL
Node Name Link.
NICS
Non-Intercompany Settlement System
NPA
Numbering Plan Area.

O
 
OPC
Own Point Code.

P
 
PGW
See Cisco PGW 2200 PSTN Gateway.
PGW Host
The Sun computing platform on which the MGC software application resides, providing call control or switching functionality. Each host controls a unique subset of the media gateways, that is, trunking gateways, access gateways, network access servers. PGW hosts are deployed in pairs for redundancy. Fault tolerance is achieved by checkpointing call context information between active and standby hosts. All stable calls are preserved in case of a switchover from one host to the other.
PIC
Primary Interexchange Carrier.
POTS
plain old telephone service. A term used to distinguish traditional human-to-human telephony services from other uses of the telephone circuits, for example, computer-to-computer data transmission over modem.
PRI
Primary Rate Interface.
PSTN
public switched telephone network.

Q
 
QoS Packet network
An IP or ATM bearer network for voice/data and signaling traffic transport through the virtual switch. The Control Signaling Network runs over the QoS Packet Network along with the bearer traffic.

S
 
SCP
Service Control Point.
Signaling Link Terminal
See Cisco SLT.
SLT
Signaling Link Terminal. See Cisco SLT.
SNMP
Simple Network Management Protocol.
SS7
Signaling System#7. This signaling system is gradually replacing older systems globally.
STP
Signal Transfer Point.

T
 
TAG
User identifier.
TDM
time-division multiplexing. In PSTN digital circuits, signals are multiplexed through the use of time slices, rather than different frequencies, phase shifts, or codes (FDM, PSK, CDM).
Time Division Multiplexing
See TDM.
TLV
Tag Length Value.
TRK
trunk.
TTL (ttl)
total.

W
 
WAN
wide-area network.