2
ASSIGNMENT TASKS
All working must be shown for numerical and analytical problems.
1.
Consider the following network. With the indicated link costs, show how Djikstra’s shortest path
algorithm works to compute the shortest path from X to all network nodes. You should present your
solution using a table similar to Table 4.3 in the textbook.
(Hint
: Review section 4.5.1 Link State Routing Algorithm) .
...........................................................................
(10 points)
Step
N’
D(s),p(s)
D(t),p(t)
D(u),p(u)
D(v),p(v)
D(w),p(w)
D(y),p(y)
D(z),p(z)
1
x
∞
∞
∞
3,x
6,x
6,x
∞
2
xv
∞
7,v
6,v
3,x
6,x
4,v
∞
3
xvy
∞
7,v
6,v
3,x
6,x
4,v
16,y
4
xvyw
∞
7,v
6,v
3,x
6,x
4,v
16,y
5
xvywu
8,u
7,v
6,v
3,x
6,x
4,v
16,y
6
xvywut
8,u
7,v
6,v
3,x
6,x
4,v
12,t
7
xvywuts
8,u
7,v
6,v
3,x
6,x
4,v
12,t
8
xvywutsz
8,u
7,v
6,v
3,x
6,x
4,v
12,t
POINT 1
: Different variations are possible in the steps (1-7) and the order in which nodes are
included in N’ – however all different variations will lead to the same least cost.
POINT 2