Information Technology Reference
In-Depth Information
Figure 6. Multi-passive-combiner hub can support more incoming/outgoing fibers to provide more
channels for heavy traffic while it can realize non-uniform channel allocation for non-uniform traffic.
3.
C
HANNEL
R
EQUIREMENTS
≤ ≤−
) carries the traffic
of all users in servicing region
i
, while node
N
carries the traffic of all users. In this section,
we determine the number of channels required by each node pair based on the traffic load and
pattern.
Let
Consider the network model shown in Figure 1. Node
i
(
1
iN
1
D
be a
channel requirement matrix
where
i
d
is the number of channels
required from node
i
to node
j
. To determine
i
d
, we consider the communication subsystem
from input
i
to output
j
of the multi-passive-combiner hub. We model this communication
subsystem as a queueing system with
i
d
servers. Based on any given traffic model and
statistics, we determine the mean packet delay
=
[]
ij
d
N
×
N
Delay
in this queueing system as a function of
i
d
using the existing methodology [25]. Then we determine the smallest
ij
d
such that the
ij
mean packet delay
Delay
is smaller than a given requirement
Delay
(e.g.,
*
Delay
is given
*
ij
to be 1 ms such that the mean delay
is at most 1 ms). This can be done by using the
Delay
ij
