Net+ 1.2 Network Topologies

You have a network that uses a logical bus topology. How do messages travel through the network?

Messages are broadcast to all devices connected to the network.

You have a network that uses a logical ring topology. How do messages travel through the network?

Messages travel from one device to the next until they reached the destination device. In a logical ring topology, messages travel to each device in turn. If the message is not intended for that device the message is forwarded to the next device on the network.

What are the (2) variations of mesh topologies?

Partial Mesh-Some redundant paths exist. Full Mesh- Every node has a point-to-point connection with every other node. Full mesh topologies are usually impractical in a standard LAN, because the number of connections increases dramatically when every new node added to the network. A separate network interface and cable for each node on the network is required. However, a full mesh topology is commonly used to interconnect routers, providing alternate paths should one path go down or become overloaded. Mesh networks are also commonly used to create redundant paths between access points in a wireless network, providing alternate paths back to the wireless controller should on access point go down or become overloaded. With this topology, every access point can communicate directly with any other access point on the wireless network.

What physical topologies can be used to support a ring logical topology?

Ring or Star Messages are sent from device to device in a predetermined order until they reach the destination device.

What topology connects each network device to a central hub?

Star

What physical topologies can be used to support a star logical topology?

Star Messages are sent directly to (and only to) the destination device.

What topology connects all devices to a trunk cable?

The bus topology connects all devices to a trunk cable.

Name the two categories of topologies.

The physical topology describes the way the network is wired. The logical topology describes the way in which messages are sent..

You have implemented an ad-hoc wireless network that doesn't employ a wireless access point. Every wireless network card can communicate directly with any other wireless network card on the network. What type of physical network topology has been implemented in this type of network?

This type of network uses a physical mesh topology. The key characteristics of a mesh topology are: There's no central connecting point. Any host can communicate directly with any other host on the network.

What is a network topology?

Topology is the term used to describe how devices are connected and how messages flow from device to device.

You have been asked to implement a wired network infrastructure that will accommodate failed connections. You don't have a large budget, so you decide to provide redundancy for only a handful of critical devices. What network topology should you implement?

in a partial mesh topology, only some redundant paths exist. A partial mesh is more practical and less expensive than a full mesh.

What is a bus physical topology?

A bus topology consists of a trunk cable with nodes either inserted directly into the trunk or tapped into the trunk using offshoot cables called drop cables. With a bus: Signals travel from one node to all other nodes. A device called a terminator is placed at both ends of the trunk cable. Terminators absorb signals and prevent them from reflecting repeatedly back and forth on the cable. It can be difficult to isolate cabling problems. A broken cable anywhere on the bus breaks the termination and prevents communications between any device on the network.

You have a small network that uses a hub to connect multiple devices. What physical topology is used?

A hub creates a network with a physical star topology. The physical star topology uses a logical bus topology, when messages are sent to all devices connected to the hub.

What is a mesh physical topology?

A mesh topology exists when there are multiple paths between any two nodes on a network. Mesh topologies are created using point-to-point connections. This increases the network's fault tolerance because alternate paths can be used when one path fails.

You want to implement a fault tolerant topology as you interconnect routers on your wide area network. What network topology would meet your needs?

A mesh topology has multiple connections at each node, increasing connectivity fault tolerance.

What devices are used to create a physical star topology?

A physical star topology uses a switch or a hub.

What is a ring physical topology?

A ring topology connects neighboring nodes until they form a ring. Signals travel in one direction around the ring: Each device on the network acts as a repeater to send the signal to the next devices. With a ring: Installation requires careful planning to create a continuous ring. Isolating problems can require going to several physical locations along the ring. A malfunctioning node or cable break can prevent signals from reaching nodes further along on the ring.

What is a star physical topology?

A star topology uses a hub or switch to connect all network connections to a single physical location. Today it is the most popular type of topology for a LAN. Within a star: All network connections are located in a single place, which makes it easy to troubleshoot and reconfigure Nodes can be added to or removed from the network easily. Cabling problems usually affect only one node.

Name the (4) physical topology types.

Bus Ring Star Mesh

What physical topologies can be used to support a bus logical topology?

Bus or Star Messages are sent to all devices connected to the bus.

You have been asked to implement a network infrastructure that will accommodate failed connections. What type of network topology provides redundancy for a failed link?

In a mesh topology, each network device is interconnected to all other network nodes. This creates multiple data paths and in the event of a failed link, the dat has an alternate route to arrive at it's destination.

What topology connects each device to a neighboring device?

In a ring topology, each device is connected to a neighboring device, until a ring is formed.

What topology does each device on the network act as a repeater, sending the signal to the next device?

In ring topologies, each device on the network acts as a repeater to send the signal to the next device.

What physical topologies can be used to support a mesh logical topology?

Mesh Messages are sent from one device to the next around the ring until they reach the destination device.