In computer networks, what is a mesh network topology and how are the nodes connected to each other in such a network?

Introduction / Context:
Network topology describes how nodes such as computers, routers, or sensors are physically or logically connected. A mesh topology is an important concept, especially in wireless networks and resilient infrastructure, because it provides multiple paths for data. Exam questions often contrast mesh networks with star, bus, or ring topologies and ask how nodes are interconnected in a mesh.

Given Data / Assumptions:

• We are dealing with topologies such as bus, star, ring, and mesh.
• Nodes may represent routers, access points, or end devices.
• Mesh networks are known for redundancy and fault tolerance.
• The question asks how nodes are connected in a mesh, not about specific routing protocols.

Concept / Approach:
In a mesh network, nodes are interconnected so that there are multiple paths between any two nodes. In a full mesh, every node has a direct link to every other node. In a partial mesh, each node connects to several others, but not necessarily all of them. The key idea is redundancy: if one link fails, data can be rerouted through another path. This is different from a star topology, where nodes connect only to a central hub, or a bus or ring, where there is typically a single main path.

Step-by-Step Solution:
Step 1: Recall that in a mesh, connectivity is dense and many direct links exist between nodes. Step 2: In a full mesh with N nodes, there are N*(N-1)/2 direct links. Step 3: Even in partial mesh networks, each node connects to multiple neighbours rather than only to a central point or two neighbours in a ring. Step 4: Option a states that each node is connected to multiple other nodes, often many or all, providing multiple paths, which matches this concept. Step 5: Option b describes a bus topology with a single backbone cable. Step 6: Option c describes a star topology with a central hub, and option d describes a ring topology with each node connected to exactly two neighbours.

Verification / Alternative check:
Think of modern wireless mesh networks used in homes or campuses. Multiple access points are placed around the building and connect to each other wirelessly, not only to a central router. If one node fails or a link is blocked, traffic can travel through alternative nodes to reach the internet. This behaviour is characteristic of mesh topology, where multiple paths exist. Traditional Ethernet bus or star networks, on the other hand, do not have this level of redundancy.

Why Other Options Are Wrong:
Option b is wrong because a bus topology uses one shared backbone and does not have multiple independent paths between nodes. Option c is incorrect because a star topology centralises connections at a hub, so if that hub fails, the whole network can be affected, which is not the idea of mesh. Option d is wrong because a ring has a single cycle and usually only two neighbours per node, with limited alternate paths compared to a mesh.

Common Pitfalls:
Students sometimes confuse mesh with ring because both can offer some redundancy, especially if the ring is bidirectional. However, mesh topologies are more flexible and allow many interconnections, while rings have strict neighbour relationships. Another pitfall is to think that mesh only applies to wireless networks; in fact, wired mesh designs exist in large enterprise and carrier networks for resilience. Understanding mesh topology helps in appreciating modern self healing wireless systems and high availability network designs.

Final Answer:
A topology in which each node is connected to multiple other nodes, often many or all of them, providing multiple paths between any pair of nodes.