Alcatel-Lucent 9500 MXC User Manual page 851

Rings Without Pt-to-Pt Overlay
3DB 23063 ADAA - Rev 004 July 2007
At the ring network nodes:
• Each drop-insert circuit uses three bus timeslots. This may also be stated as:
each drop-insert circuit uses the equivalent of one-and-one-half bus circuits.
• Pass-through circuits use the standard two-timeslots, one for Tx and one for Rx
(one circuit on the bus).
Ring node capacity rules may therefore be stated as:
Ring Type
NxE1
NxDS1
Where:
• R = The ring capacity (total number of circuits on the ring)
• d = The drop-insert circuit capacity (number of circuits dropped and inserted
at the node)
This is illustrated in Figure E-5 for a 64xE1 ring node with a 16xE1 drop-insert.
Ring Node Bus-Capacity Example
Figure E-5.
R = 64xE1
RAC
16 timeslots
dropped
R = Ring capacity = 64xE1
d = Drop-insert capacity = 16xE1
Bus timeslot capacity used = 64 + (64-16) + 16 + 16 = 144
Bus circuit capacity used = 144/2 = 72
Rule Based on Number
of E1 or DS1 Circuits
R + d/2 100
R + d/2 128
64 timeslots
passed
RAC
64-16 timeslots
passed
Primary Ring
16 timeslots
inserted
DAC
16xE1
9500 MXC User Manual
Rule Based on Number
of E1 or DS1 Timeslots
2R + d 200
2R + d 256
y g
R = 64xE1
Vol. VI-E-5