1
3
2
1
3
2
N-2
N
N-1
Real-time package
1
3
2
N-k
High priority package
Regular package
1
3
2
N-2
N
N-1
P
1
L
N
Delay caused by sitting in an queue increase
a probability of fail for RT package
Knowing the shape of a curve P(L) and current state of desperation for i-thpackages P i (t)
it is possible to create an algorithm of desperation handling (ADH) elevating a package
from, say,
to , etc.
P N-2
P 2
1
t
DL
Delay caused by i-throuter for a package
i q
o q
RP i
Structure of Package delay:
iq -incoming queue delay
Rpi -routing processing for i-thpackage
oq -outcoming queue delay
DL - desperation level for a package
(a)
(b)
(c)
Fig. 19.8 a Various lengths of queues for different types of packages. b Handling level of
package desperation at router level. c Illustration of desperation level for a package
19.10 Router Level of Desperation Control
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