GATE Networks 2

Question 1

In a network with n nodes, the maximum number of edges in a simple undirected graph is:

Accepted Answer

n(n-1)/2

Answer

A simple undirected graph can have at most one edge between any two nodes, giving n(n-1)/2 edges.

Question 2

Which routing algorithm guarantees the shortest path by exploring nodes in order of their cumulative distance from the source?

Accepted Answer

Dijkstra's algorithm

Answer

Dijkstra's algorithm uses a greedy approach with a priority queue to always expand the closest unvisited node, guaranteeing shortest paths in graphs with non-negative weights.

Question 3

A token ring network with 4 stations has a token rotation time of 40 ms. If each station transmits for at most 10 ms, what is the maximum efficiency?

Accepted Answer

50%

Answer

With 4 stations each transmitting 10 ms in a 40 ms rotation, total transmission = 40 ms, but overhead means efficiency = 4×10/(4×10 + token overhead); assuming 40 ms total cycle, efficiency = 40/80 = 50%.

Question 4

The Nyquist theorem states that the maximum data rate of a noiseless channel with bandwidth B Hz and M discrete signal levels is:

Accepted Answer

2B log2(M)

Answer

Nyquist's formula: Maximum data rate = 2B log2(M) bits per second for a noiseless channel.

Question 5

Which field in the IPv4 header is used to prevent packets from circulating indefinitely in the network?

Accepted Answer

Time to Live (TTL)

Answer

The TTL field is decremented by each router, and a packet is discarded when TTL reaches zero, preventing infinite looping.

(GATE) Graduate Aptitude Test in Engineering Practice Test

(GATE) Graduate Aptitude Test in Engineering Practice Test

GATE Networks 2