Appendix to Course Project Description (1)

The State Machine

TCP

Local MemoryConsole

A Set of Commands:

L NeighborID cost(neighborID link cost info)

D NeighborID diff-cost(change of link to neighborID - d)

N NeigbhorID Dest Dist(new min Distance vector info from the neighbor ID to dist- newval)

P (no parameter)(print out the distance Vector table)

U (no parameter)(print out all updated Distance vector info toIts neighbors)

F (no parameter)(finish initialization)

Q (no parameter)(quit)

stdin

stdout

(interface)(running the DV algorithm)

Node 1

Appendix to Course Project Description (2)

1 352

7->2

2

Examples of the Commends:

L NeighborID cost(neighborID link cost info)Examples:L 2 2L 3 7

D NeighborID diff-cost(change of link to neighborID - d)D 3 -5

N NeigbhorID Dest Dist(new min Distance vector info from the neighbor ID to dest - newval)

N 3 2 4

4

2

Test Instance (at node 1):

Prompt> L 2 2Prompt> L 3 7Prompt> L 4 infPrompt> P Dest Neighbors 2 32 2 Inf3 Inf 74 Inf InfPrompt> UDest Neighbors 2 32 2 3 7 4 Inf Prompt > F

Prompt>N 3 4 2Prompt N 3 2 5Prompt>PDest Neighbors 2 32 2 123 Inf 74 Inf 9Prompt>D 3 -5Prompt>PDest Neighbors 2 32 2 73 Inf 24 Inf 4

Appendix to Course Project Description (3)1 Initialization: 2 for all adjacent nodes v: 3 D (*,v) = infty /* the * operator means "for all rows" */ 4 D (v,v) = c(X,v) 5 for all destinations, y 6 send min D (y,w) to each neighbor /* w over all X's neighbors */78 loop 9 wait (until I see a link cost change to neighbor V 10 or until I receive update from neighbor V) 11 12 if (c(X,V) changes by d) 13 /* change cost to all dest's via neighbor v by d */ 14 /* note: d could be positive or negative */ 15 for all destinations y: D (y,V) = D (y,V) + d 16 17 else if (update received from V wrt destination Y) 18 /* shortest path from V to some Y has changed */ 19 /* V has sent a new value for its min DV(Y,w) */ 20 /* call this received new value is "newval" */ 21 for the single destination y: D (Y,V) = c(X,V) + newval 22 23 if we have a new min D (Y,w)for any destination Y 24 send new value of min D (Y,w) to all nighbors 25 26 forever

1 Initialization: While(1){ read commands (started by “L” , “P”, “U”,

“F”) to mem from stdin (or TCP read) if (“F” command) break; if (“P” or “U”) write to stdout (or TCP write) ……}78. While(1){ read commands (started by “D”,”N”, “P”,

“U”, “Q”) to mem from stdin (or TCP read)

if (“Q” command) break; if (“P” or “U”) write to stdout (or TCP write)

……

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