How many cables are needed to connect 6 computers in a fully connected mesh topology?
- A.12
- B.15
- C.18
- D.30
Correct answer
Explanation
The correct answer is B, 15. In a full mesh every node is joined directly to every other node, so the number of links equals the number of pairs that can be formed from the nodes, given by the formula n(n-1)/2. Putting n equal to 6 gives 6 multiplied by 5, that is 30, divided by 2, which equals 15 cables; each machine also needs 5 network ports, so the port count is n(n-1) in total. Option A is wrong because 12 would be twice the number of nodes and has no basis in the formula. Option C is wrong because 18 is three times the number of nodes and again does not follow from counting pairs. Option D is wrong because 30 is the value of n(n-1), which counts each link twice, once from either end, and must be halved since one cable serves both directions.
Read the full article: Computer Networks: Topologies, Devices and OSI Layers
Practice Questions
View allIn terms of computers, the set of ways in which an adversary can enter a system and can potentially cause damage is called:
- A.Attack Surface
- B.Attack Signature
- C.Attack Pattern
- D.Attack Path
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- A.Modulator
- B.Mouse
- C.Plotter
- D.Keyboard
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Read the full explanation →What is the full form of GPRS in mobile computing?
- A.General Packet Radio Service
- B.General Packet Route service
- C.General Package Radio Service
- D.General Packet Radiation Service
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Read the full explanation →In which network topology is every node connected to a single central device?
- A.Bus topology
- B.Ring topology
- C.Star topology
- D.Mesh topology
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Read the full explanation →A router works at which layer of the OSI reference model?
- A.Physical layer
- B.Data Link layer
- C.Network layer
- D.Transport layer
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A router joins two or more different networks and decides, for every packet, which outgoing line will carry it towards its destination.
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