Telecom

ISDN user-network call control: SETUP, CALL PROCEEDING, ALERTING, CONNECT, DISCONNECT, RELEASE. Information elements carry bearer capabil…

Primary Rate ISDN: T1 23B+D or E1 30B+D with a 64 kb/s D-channel for Q.931/LAPD. Timeslots map B-channels; framing and line coding come f…

ITU umbrella for packet multimedia: H.225.0 call signaling/RAS, H.245 media control, and RTP/RTCP media. Gatekeepers provide admission an…

SS7 Message Signal Units carry user-part payloads over MTP. Level-2 framing wraps length, sequence/ACK bits, and SIO/SIF; Level-3 routing…

SS7 call-control user part for trunk setup: IAM, ACM, ANM, REL, RLC and related messages. Circuit identification codes bind signaling to …

SS7 link-layer framing with flags, sequence numbers (BSN/FSN), FIB/BIB retransmission bits, and FISU/LSSU/MSU SU types. Alignment procedu…

SS7 network layer providing routing labels (DPC/OPC/SLS), linkset/route management, and discrimination to user parts. It carries ISUP, SC…

SS7 connectionless and connection-oriented transport with global title translation (GTT) for number-based routing. It underpins TCAP and …

Transaction and dialogue layer over SCCP for intelligent-network and mobile services. Begin/Continue/End/Abort components carry MAP, CAP,…

GSM/UMTS Mobile Application Part over TCAP for location update, authentication, SMS, and subscriber data management. Operation codes and …

CAMEL Application Part for prepaid and intelligent services in mobile networks. InitialDP and subsequent event reports drive SCP interact…

Intelligent Network Application Part for fixed-network service control over TCAP. CS-1/CS-2 operations resemble CAP but target wireline S…

SIGTRAN adaptation that replaces MTP2 over SCTP while preserving MTP3 peer semantics between IP-connected SS7 nodes. Link status and sequ…

SIGTRAN adaptation that backhauls MTP2 user primitives over SCTP between a signaling gateway (SGP) and application server (ASP). It separ…

SIGTRAN MTP3 user adaptation over SCTP that carries ISUP/SCCP payloads with routing keys for IP-SS7 interconnect. ASPs and SGPs exchange …

SIGTRAN SCCP User Adaptation delivering SCCP-user data over SCTP without a full MTP3 stack on the application server. Common for TCAP app…

ISDN Basic Rate Interface providing two 64 kb/s B-channels plus a 16 kb/s D-channel for Q.931 signaling (2B+D). S/T and U interfaces diff…

Channel Associated Signaling and MFC-R2 multi-frequency compelled trunk signaling used on legacy TDM interconnects. Line signaling may be…

Time-division multiplexed digital trunks such as T1 (24×DS0) and E1 (32 timeslots) framed per G.704 and related recommendations. Framing,…

Media Gateway Control Protocol in which Call Agents issue CRCX/MDCX/DLCX and signal requests to subordinate media gateways. SDP in the te…

H.248/Megaco media-gateway control using terminations, contexts, and descriptors for large carrier gateways. It succeeds MGCP conceptuall…

Digital Mobile Radio — an ETSI TDMA LMR standard with two slots in a 12.5 kHz channel for voice, data, and trunking control. Tier I/II/II…

APCO Project 25 public-safety digital radio with FDMA Phase 1 and TDMA Phase 2 common air interfaces. IMBE/AMBE vocoders, trunking contro…

H.323 call signaling and RAS: Q.931-derived Setup/Alerting/Connect on the Call Signaling Channel plus gatekeeper discovery/registration. …

H.323 multimedia control protocol for capability exchange, master/slave determination, and logical channel open/close. Fast Start and H.2…

Local Number Portability lets a subscriber keep an E.164 number when changing carriers. Originating switches query an NPDB (often via TCA…

Calling Name Delivery presents a display name for the calling party at the terminating set. Classic wireline dips query a CNAM/LIDB datab…

Line Information Database holds per-line attributes used by calling-card, collect, third-number billing, and CNAM services. Queries trave…

North American Advanced Intelligent Network defines detection points, triggers, and SCP transactions (often over TCAP) for number transla…

Toll-free / 8XX service translates a dialed toll-free number to a routing number or carrier via an SCP (SMS/800, RespOrg databases) over …

ANSI-41 (IS-41) is the North American mobile application protocol family over TCAP for AMPS/TDMA/CDMA mobility: registration, authenticat…