ISDN User Partwikipedia
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).
ISUP

Telephone call

telephone callcallphone call
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).
Most telephone calls through the PSTN are set up using ISUP signalling messages or one of its variants between telephone exchanges to establish the end to end connection.

Signalling System No. 7

SS7SS7 networkCCS7
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).
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.

Public switched telephone network

public switched telephone networkPSTNtelephone network
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).
The call is switched using a call set up protocol (usually ISUP) between the telephone exchanges under an overall routing strategy.

Message Transfer Part

MTPQ.710MTP layer 3
ISUP messages can be sent using the services of the Message Transfer Part, or, less often, the Signalling Connection Control Part.
Some examples of parts at Level 4 are SCCP, ISUP, TUP, and, in the UK, IUP.

Trio AB

While Trio was built during SS7/ISUP, it has been adapting to use VoIP in its newer products.

Enhanced 9-1-1

E911enhanced 9-1-1enhanced 911
Some of the upgraded PSAPs can receive calls on ISUP trunks controlled by the SS7 protocol.

Bearer-Independent Call Control

BICC
BICC signaling messages are nearly identical to those in ISDN User Part (ISUP); the main difference being that the narrowband circuit identification code (CIC) has been modified.

M3UA

MTP level 3 User Adaptation'' protocol (M3UA)
M3UA enables the SS7 protocol's User Parts (e.g. ISUP, SCCP and TUP) to run over IP instead of telephony equipment like ISDN and PSTN.

Business telephone system

PBXprivate branch exchangekey telephone system
For the option to call from IP network to the circuit-switched PSTN (SS7/ISUP), the hosted solutions include interconnecting media gateways.

HP OpenCall

It is most commonly described as a suite of software and hardware applications which allow implementation of common telecom operator services such as voicemail, sms (short message service), prepaid, billing, hlr, etc. It implements industry standard telecom protocols and standards such as SS7, ISUP, TCAP, SIP, MRCP, RTSP, and VoiceXML.

Signal Transfer Point

signal transfer pointSignal Transfer Point (STP)signalling transfer points
A typical application would be for two SEPs to agree on the use of a shared data path (e.g., using ISUP to initiate a voice call between a user on one SEP and a user on the second SEP).

List of CDMA terminology

eHRPDCDMA technology term
ISUP – Integrated Services User Part

Telephone User Part

TUP
It has now largely been replaced by ISUP.

Aculab

Prosody X variants can also be used with Aculab's protocol stacks to connect to SS7 networks for ISUP, signalling monitoring, and non-call related TCAP signalling applications.

IP Multimedia Subsystem

IMSIP Multimedia Subsystem (IMS)HSS
For signalling, CS networks use ISDN User Part (ISUP) (or BICC) over Message Transfer Part (MTP), while IMS uses SIP over IP. For media, CS networks use Pulse-code modulation (PCM), while IMS uses Real-time Transport Protocol (RTP).

Session Initiation Protocol

SIPsession initiation protocolSession Initiation Protocol (SIP)
SIP-I, or the Session Initiation Protocol with encapsulated ISUP, is a protocol used to create, modify, and terminate communication sessions based on ISUP using SIP and IP networks.