Public Switched
Telephone Network (PSTN II/II)

Topics today in PSTN

Switching in public networks

Circuit switching

Packet switching

Connection-oriented and connectionless switching

Transfer modes & connections summarized

Example of cell switching:
Distributed queue dual buss (DQDB)

Connecting into PSTN exchange: Equipment in the access network

Local exchange

Subscriber stage

Exchange control functions

Exchange user services (examples)

The space-switch (used as a cross-switch and concentrator)

The time-switch

The time-space-time (TST) switch

PSTN ISDN exchange
interfaces (Q.512)

Exchange interfaces and tasks, V1

Exchange interfaces and tasks, V2-V4

Exchange interfaces and tasks, V5

Connecting the local loop:
Line interface circuit (LIC)

Line interface circuit components

The hybrid circuit

The hybrid-circuit

The hybrid circuit summarized

Network echo suppressor (NES)

Network echo canceller (NEC)

PSTN operation and maintenance (Q.513)

Modern PSTN hierarchy

PSTN Hierarchy cont.

Subscriber signaling for local calls

Inter-exchange signaling

Inter exchange signaling (cont.)

Example of inter-exchange signaling

Inter-exchange signaling (cont.)

A case study: DX 200 Exchange

A case study: DX 200 Exchange

A case study: DX 200 Exchange (cont.)

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