Signalling System No. 7

SS7Signaling System 7Signalling System 7Signaling System No. 7Signaling SystemSS7 NetworkBSSAP+CCS7Q.713Signaling
'''Signaling System No. 7 (SS7''') is a set of telephony signaling protocols developed in 1975, which is used to set up and tear down telephone calls in most parts of the world-wide public switched telephone network (PSTN).wikipedia
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SMS

Short Message Servicetext messagetext messages
The protocol also performs number translation, local number portability, prepaid billing, Short Message Service (SMS), and other services.
The Mobile Application Part (MAP) of the SS7 protocol included support for the transport of Short Messages through the Core Network from its inception.

Signaling (telecommunications)

signalsignalingout-of-band signaling
7 (SS7''') is a set of telephony signaling protocols developed in 1975, which is used to set up and tear down telephone calls in most parts of the world-wide public switched telephone network (PSTN).
Out-of-band signaling has been used since Signaling System No. 6 (SS6) was introduced in the 1970s, and also in Signalling System No. 7 (SS7) in 1980 which became the standard for signaling among exchanges ever since.

SIGTRAN

The Internet Engineering Task Force (IETF) has defined the SIGTRAN protocol suite that implements levels 2, 3, and 4 protocols compatible with SS7.
SIGTRAN is the name, derived from signaling transport, of the former Internet Task Force (I) working group that produced specifications for a family of protocols that provide reliable datagram service and user layer adaptations for Signaling System and ISDN communications protocols.

Public switched telephone network

PSTNpublic telephone networktelephone network
7 (SS7''') is a set of telephony signaling protocols developed in 1975, which is used to set up and tear down telephone calls in most parts of the world-wide public switched telephone network (PSTN). The Telephone User Part (TUP) was adopted in Europe and the Integrated Services Digital Network (ISDN) User Part (ISUP) adapted for public switched telephone network (PSTN) calls was adopted in North America.
Later, more sophisticated address signaling, including multi-frequency signaling methods, enabled direct-dialed long distance calls by subscribers, culminating in the Signalling System 7 (SS7) network that controlled calls between most exchanges by the end of the 20th century.

Local number portability

number portabilityportported
The protocol also performs number translation, local number portability, prepaid billing, Short Message Service (SMS), and other services. Other examples include Intelligent Network and local number portability databases.
Providers use SS7 to route calls throughout the US/Canada network.

Stream Control Transmission Protocol

SCTPIPPROTO_SCTPStream Control Transmission Protocol (SCTP)
it is layered on the Stream Control Transmission Protocol (SCTP) transport mechanism for use on Internet Protocol networks, such as the Internet.
The designers of SCTP originally intended it for the transport of telephony (Signaling System 7) over Internet Protocol, with the goal of duplicating some of the reliability attributes of the SS7 signaling network in IP.

ISDN User Part

ISUPRelease (ISUP)
The Telephone User Part (TUP) was adopted in Europe and the Integrated Services Digital Network (ISDN) User Part (ISUP) adapted for public switched telephone network (PSTN) calls was adopted in North America. OSI layers 1 to 3 are provided by the Message Transfer Part (MTP) and the Signalling Connection Control Part (SCCP) of the SS7 protocol (together referred to as the Network Service Part (NSP)); for circuit related signaling, such as the BT IUP, Telephone User Part (TUP), or the ISDN User Part (ISUP), the User Part provides layer 7.
The ISDN (Integrated Services Digital Network) User Part or ISUP is part of Signaling System No. 7 (SS7), which is used to set up telephone calls in the public switched telephone network (PSTN).

Telephony

digital telephonytelephonedigital
7 (SS7''') is a set of telephony signaling protocols developed in 1975, which is used to set up and tear down telephone calls in most parts of the world-wide public switched telephone network (PSTN).

Signal Transfer Point

Signaling Transfer PointSignal Transfer Point (STP)signalling transfer points
When operating in the quasi-associated mode, SS7 signaling progresses from the originating switch to the terminating switch, following a path through a separate SS7 signaling network composed of signal transfer points. The network can be made up of several link types (A, B, C, D, E, and F) and three signaling nodes – Service Switching Points (SSPs), Signal Transfer Points (STPs), and Service Control Points (SCPs).
A Signal Transfer Point (STP) is a router that relays SS7 messages between signaling end-points (SEPs) and other signaling transfer points (STPs).

Blue box

2600 Hza 2600-hertz-soundBlue box (phreaking)
As the bearer channel was directly accessible by users, it was exploited with devices such as the blue box, which played the tones required for call control and routing.
The death of blue boxing came in the mid-to-late 1990s when telephone companies, becoming aware of the problem, eventually moved to out-of-band signaling systems with separate bearer and signaling channels (such as Common Channel Interoffice Signaling and Signaling System 7).

Business telephone system

PBXprivate branch exchangePABX
This is the case for earlier analogue trunks, multi-frequency (MF) and R2 digital trunks, and DSS1/DASS PBX trunks.
For the option to call from IP network to the circuit-switched PSTN (SS7/ISUP), the hosted solutions include interconnecting media gateways.

ITU-T

CCITTITU Telecommunication Standardization SectorTelecommunication Standardization Sector
The SS7 protocol is defined for international use by the Q.700-series recommendations of 1988 by the ITU-T.

Service control point

SCP(SCPs)gsmSCP
The network can be made up of several link types (A, B, C, D, E, and F) and three signaling nodes – Service Switching Points (SSPs), Signal Transfer Points (STPs), and Service Control Points (SCPs).
Standard SCPs in the telecom industry today are deployed using SS7, SIGTRAN or SIP technologies.

Intelligent Network

INAdvanced Intelligent NetworkIntelligent Network (IN)
Other examples include Intelligent Network and local number portability databases.
IN is supported by the Signaling System #7 (SS7) protocol between network switching centers and other network nodes owned by network operators.

Integrated Services Digital Network

ISDN ISDNISDN30
The Telephone User Part (TUP) was adopted in Europe and the Integrated Services Digital Network (ISDN) User Part (ISUP) adapted for public switched telephone network (PSTN) calls was adopted in North America.
Between telephone company switches, the signaling is performed via SS7.

Message Transfer Part

MTPMTP 2MTP layer 3
OSI layers 1 to 3 are provided by the Message Transfer Part (MTP) and the Signalling Connection Control Part (SCCP) of the SS7 protocol (together referred to as the Network Service Part (NSP)); for circuit related signaling, such as the BT IUP, Telephone User Part (TUP), or the ISDN User Part (ISUP), the User Part provides layer 7.
The Message Transfer Part (MTP) is part of the Signaling System 7 (SS7) used for communication in Public Switched Telephone Networks.

Telephone exchange

exchangescentral officeexchange
When operating in the quasi-associated mode, SS7 signaling progresses from the originating switch to the terminating switch, following a path through a separate SS7 signaling network composed of signal transfer points. Due to its richness and the need for an out-of-band channel for its operation, SS7 is mostly used for signaling between telephone switches and not for signaling between local exchanges and customer-premises equipment.
Before Signalling System 7, Bell System electromechanical switches in the United States originally communicated with one another over trunks using a variety of DC voltages and signaling tones, replaced today by digital signals.

Mobile Application Part

MAP
TCAP provides transaction capabilities to its Users (TC-Users), such as the Mobile Application Part, the Intelligent Network Application Part and the CAMEL Application Part.
The Mobile Application Part (MAP) is an SS7 protocol that provides an application layer for the various nodes in GSM and UMTS mobile core networks and GPRS core networks to communicate with each other in order to provide services to users.

DS0A

In Europe they are usually one (64 kbit/s) or all (1,984 kbit/s) timeslots (DS0s) within an E1 facility; in North America one (56 or 64 kbit/s) or all (1,536 kbit/s) timeslots (DS0As or DS0s) within a T1 facility.
DS0A is the interface most commonly used for SS7 networks in the US.

Common-channel signaling

Common Channel SignalingCommon Channel Interoffice Signalingcommon
SS6 and SS7 are referred to as common-channel signaling (CCS) protocols, or Common Channel Interoffice Signaling (CCIS) systems.
The most common CCS signaling methods in use are Integrated Services Digital Network (ISDN) and Signalling System No. 7 (SS7).

Service switching point

MSSP(SSPs)Service Switching Points
The network can be made up of several link types (A, B, C, D, E, and F) and three signaling nodes – Service Switching Points (SSPs), Signal Transfer Points (STPs), and Service Control Points (SCPs).
The service switching point uses the Signalling System No. 7 (SS7) protocols which are responsible for the call setup, management, and termination with other service switching points.

Signaling System No. 5

#5Signaling System 5, (SS5)
Signaling System No. 5 and earlier systems used in-band signaling, in which the call-setup information was sent by playing special multi-frequency tones into the telephone lines, known as bearer channels.

Caller ID

caller line identificationCaller-IDCalling Line Identification
Some of the first such services were call management related, call forwarding (busy and no answer), voice mail, call waiting, conference calling, calling name and number display, call screening, malicious caller identification, busy callback.
A SS7 (or Signalling System 7) TCAP query may be launched by the called party's central office, in order to retrieve the information for Calling Name delivery to the caller ID equipment at the consumer's location, if the caller's name has not already been associated with the calling party's line at the originating central office.

Signalling Connection Control Part

SCCPNSPSignaling Connection and Control Part
OSI layers 1 to 3 are provided by the Message Transfer Part (MTP) and the Signalling Connection Control Part (SCCP) of the SS7 protocol (together referred to as the Network Service Part (NSP)); for circuit related signaling, such as the BT IUP, Telephone User Part (TUP), or the ISDN User Part (ISUP), the User Part provides layer 7.
The Signalling Connection Control Part (SCCP) is a network layer protocol that provides extended routing, flow control, segmentation, connection-orientation, and error correction facilities in Signaling System 7 telecommunications networks.

INAP

Intelligent Network Application PartIntelligent Network Application Part (INAP)
TCAP provides transaction capabilities to its Users (TC-Users), such as the Mobile Application Part, the Intelligent Network Application Part and the CAMEL Application Part.
It is part of the Signalling System No. 7 (SS7) protocol suite, typically layered on top of the Transaction Capabilities Application Part (TCAP).