Information Technology Reference
In-Depth Information
bisection method because the mean packet delay
Delay
is a monotonic decreasing function
ij
i d . The details of determining the channel requirement
d
of the number of channels
for all
ij
1, ij N
≤≤ are given as follows.
low
ij
up
ij
d
d
Delay
>
Delay
*
1. Select
and
such that
and
ij
low
dd
=
ij
ij
*
Delay
Delay
.
ij
up
dd
=
ij
ij
up
low
up
2. If (
dd
)
= then
1
dd
=
and STOP.
ij
ij
ij
ij
up
low
3. While (
dd
)
> do the following
1
ij
ij
4. Begin
low
up
dd
+
ij
ij
mid
ij
5.
d
=
2
mid
Delay
=
Delay
*
dd
=
6. If
, then
and STOP.
ij
mid
ij
ij
dd
=
ij
ij
*
low
mid
7. Else if
Delay
>
Delay
, then
d
=
d
.
ij
ij
ij
mid
dd
=
ij
ij
*
dd
up
=
mid
8. Else if
Delay
<
Delay
, then
.
ij
ij
ij
mid
dd
=
ij
ij
9. End_while
10.
dd
=
up
and STOP.
ij
ij
We now consider a specific traffic model based on the above framework. Let the packet
arrival process from node i to node j be Poisson with mean packet rate i α , and the packet
size be exponentially distributed with mean packet transmission time 1 β . The
communication subsystem from node i to node j can be modeled as an
Md queueing
M
/
/
ij
system. The mean packet delay
Delay can be found to be :
ij
d
(
d
ρ
)
C
ij
1
ij
ij
(1)
=
+
Delay
ij
2
β
dd
!(1
ρ
)
β
ij
ij
ij
where
ρ αβ
=
d
and
ij
ij
ij
1
(2)
C
=
d
d
1
k
(
d
ρ
)
(
d
ρ
)
ij
ij
ij
ij
ij
ij
+
k
!
d
!(1
ρ
)
k
=
0
ij
ij             Search WWH ::

Custom Search