Computer Networks (test-2)

The topology with the highest reliability is

• Ring

• Bus

• Mesh

• Star

Answer explanation

The mesh topology offers the highest reliability because it connects each device to multiple others, ensuring that if one connection fails, data can still be routed through other paths, unlike ring, bus, or star topologies.

Mechanism to protect private networks from outside attack is

• Anti virus

• Firewall

• Digital Signature

• Formatting

Answer explanation

A firewall is a security mechanism that monitors and controls incoming and outgoing network traffic based on predetermined security rules, effectively protecting private networks from outside attacks.

Start and Stop bits are used in serial communications for _____

• Error Detection

• Error Correction

• Showing down the communication

• Synchronization

Answer explanation

Start and Stop bits are essential in serial communications for synchronization, ensuring that the sender and receiver are aligned in timing for data transmission.

In which of the following networks token bus will be used

• Point to Point

• Unicast

• Broadcast

• Multicast

Answer explanation

Token bus is a network protocol that operates in a unicast manner, allowing communication between a single sender and a single receiver. Therefore, the correct choice is Unicast.

The main function of the network layer is routing ____from the source machine to the destination machine

• Packets

• Frames

• Bit stream

• Segments

Answer explanation

The network layer is responsible for routing packets, which are units of data sent over a network. Frames operate at the data link layer, bit streams are raw data, and segments are used at the transport layer.

Which of the following topology requires multipoint connection

• Star

• Bus

• Mesh

• Ring

Answer explanation

The bus topology requires a multipoint connection as all devices share a single communication line. In contrast, star, mesh, and ring topologies use point-to-point connections between devices.

Number of links in an eight node fully connected mesh network is

• 16

• 28

• 46

• 64

Answer explanation

In a fully connected mesh network with n nodes, the number of links is given by n(n-1)/2. For 8 nodes, it is 8(8-1)/2 = 28. Thus, the correct answer is 28.

Which network topology requires a central controller or hub ?

• Bus

• Star

• Mesh

• Ring

Answer explanation

The star topology requires a central controller or hub to connect all devices. Unlike bus, mesh, or ring topologies, where devices are interconnected without a central point, the star configuration relies on a single hub for communication.

In a star topology, if the central hub fails, what happens to the network?

• Only the hub is affected

• All nodes are disconnected

• Only some nodes are affected

• All nodes remain connected

Answer explanation

In a star topology, the central hub is crucial for communication. If the hub fails, all nodes lose their connection to each other, resulting in all nodes being disconnected. Thus, the correct answer is that all nodes are disconnected.

In a mesh topology, how many connections are needed for a network of n nodes?

• n^2

• 2n

• n(n-1)/2

• n-1

Answer explanation

In a mesh topology, each node connects to every other node. For n nodes, the number of unique connections is given by the formula n(n-1)/2, which accounts for each pair of nodes being connected once.