Bio-Inspired Computing and Networking

340

■

Bio-Inspired Computing and Networking

have a greater level. The traffic density of the lowest nodes in the level is D

1

= λ as

they will only forward the packets they generate, and not route any other traffic. A

level 1 node will send its messages to any node with a higher level. There are L − 1

levels that are higher, and they will thus each expect to receive (and subsequently be

responsible for forwarding) λ/(L − 1) messages. Thus, in general, we can express

the traffic density at each level in the hierarchy using the recursive equation

D

k

= D

k−1



1 +

1

L −k + 1



, (12.16)

where 1 ≤ k ≤ L.

33

This can be simplified to obtain an expression for the traffic volume ...