4
Circuit switching
Time switch
- Makes switching between time slots
- In the figure incoming slot 3 is moved to
outgoing slot 3 for one voice direction
outgoing slot 3 for one voice direction
- Each coming timeslot stored in Speech Store (SS)
- Control store (CS) determines the order the slot
are read from SS
are read from SS
- The info in CS is determined during setup
phase of the call
phase of the call
Space switch
- makes switching
between PCM lines
- works
with electronic gates
controlled by CS
Cross-point
controlled by CS
Circuit switching
- dedicated path
- constant delay/bandwidth
- voice/data
- paid by time
- examples: PSTN, VPN
- constant delay/bandwidth
- voice/data
- paid by time
- examples: PSTN, VPN
TDMA