Assignment 1 Comparison between Network Topologies Name: Mahmoud Yehia Mahmoud Ali Kamel
Student Number: 20043250
1 Abstract Network topology is the arrangement of the various nodes of a computer network, essentially, it is the topological structure of a network and may be depicted physically or logically, graphically mapping the links between nodes results in a geometric shape that can be used to describe the physical topology of the network. Here is a comparison between various Topologies.
2 Comparison Topology
Architecture/ organization
Star
A network topology in which peripheral nodes are connected to a central node(such as a hub, switch, or router) which rebroadcasts all transmissions received from any peripheral node to all peripheral nodes on the network, including the originating node. All peripheral nodes may thus communicate with all others by transmitting to, and receiving from, the central node only is a network topology in which there is a single line (the bus) to which all nodes are connected, and the nodes connect only to this bus. This is a bus line going through a city. The cable has a small cap installed at the end, called a terminator. The terminator prevents signals from bouncing back and causing network errors. Like a series of pipes that water travels through A network topology in which every node has exactly two branches connected to it. A starwired ring topology may appear (externally) to be the same as a star topology. Internally, the MAU (multistation access unit) of a star-wired ring contains wiring that allows information to pass from one device to another in a circle or ring. point-to point links in a closed loop.
Bus
Ring
Mesh
Token-ring
Tree
Routing Methodology
Complex ity
Expansio n
Reliability
Cost
Cabling Concerns
Security
Delay/Respons e time
All information passes through the central network connection.
Very simple(Us ed for LANs)
Add a new computer by plugging in a new cable from the computer to the connection device.
When one computer goes down, the rest of the network is unaffected. If the connection device goes down, then the network is down.
More expensive of the simple topologies, it requires costly connection device. Usually cheaper than a hybrid network.
Uses twisted pair cable. Requires large amounts of cable. No more than 100 meters from the computer to the connection device.
denial of service attack
Excellent in terms of distance
One computer at a time sends information. Information goes along the cable and the computer accesses the information off the cable.
The Simplest one(Used for LANs)
To add a computer, you must shut down the network and disconnect the cable from the existing computers.
If one computer malfunctions , the entire network goes down.
A cheaper network since there is usually one continuous copper cable.
Single continuous cable connects the devices. Terminator is required at each end of the cable. Uses coaxial or twisted pair cabling.
Not secure cause broadcast
Delay cause broadcast
Information goes in one direction around the ring and passes along the ring until it reaches the correct computer.
(Used for LANs)
Cable between the computers must be broken to add a new computer, so the network is down until the new device is back online.
If there's a break in the cable or an error in the network, information continues to transfer through the rest of the ring until reaching the point of the break. This makes troubleshooting easy.
One of the more expensive topologies due to high cable costs.
Requires more cabling than other topologies. Uses twisted pair.
The least security as the information Intended for one machine must pass all the others
good
A network topology in which there are at least two nodes with two or more paths between them.
Often used across long distances. Information transfer can happen in different ways, depending on the other topologies.
Used for WANs
Troubleshootin g is most difficult in this topology because of the variety of technologies.
Expensive, large, and usually complicated.
Cabling depends on the types of networks. Can use twisted pair and coaxial cable. Also incorporates fiber optic cabling over long distances.
A mesh needs secure links, routing, and forwarding
Trade off with cost
Token-passing networks move a small frame, called a token, around The network. Possession of the Token grants the right to transmit. If a node receiving the token has no information to send, it passes the token to the next end station And the process repeats itself. Each station can hold the token For a maximum period of time. The nodes are arranged as a tree. The tree topology is a generalization of the bus topology. The transmission medium is a branching cable with no closed loops. The tree layout begins at a point known as the head end (Root), where one or more cables start, and each of these may have branches. The branches in turn may have additional branches to allow quite complex layouts.
A speciallyformatted frame, called a token, travels around the ring, stopping at each host.. The destination host takes the data out of the frame. No data collisions.
(Used for LANs)
Connection devices make combining different networks and different topologies easy. The more workstation s causes slower the response time Not very flexible or scalable
A single malfunctioning workstation can disable the network
Fairly low
Twisted Pair
Low security as it physically star but logically ring
Not bad (No data collisions.)
a transmission from any station Propagates throughout the medium and can be received by all other stations. . A host that is a branch off from the main tree is called a ‘leaf’.
Used for WANs
The simplest to install and extend extra Stations in a daisy chain manner,
N.W partitioned easily, but partitions still work.
Costly because it is heavily cabled
Overall length of each segment is limited by the type of cabling used. (Coax - Twisted Pair – Fiber)
Low security as it physically star but logically bus
Possible traffic jams.
Fully connected
A fully connected topology is a network topology in which there is a direct link between all pairs of nodes. In a fully connected network with n nodes, there are n (n-1)/2 direct links. Synonym fully connected mesh network.
Many paths with fault tolerance
Used for WANs
difficult to Expand
The most reliable one, doesn't have single point of failure/attack
Expensive due to high cable costs.
All kind of cables that can be used with LAN and WAN
Secured
Too slow, add more links.
3 Conclusion Choice of network topology must be done very carefully and professionally based on many design parameters such as security, complexity, reliability, cost and many other design parameters that define the best topology that can meet effectively the requirements of a network infrastructure.
4 References 1- “types of network topology” http://www.studytonight.com/computer-networks/network-topology-types 2- “network topologies” https://www.edrawsoft.com/Network-Topologies.php 3- “network topology comparison” https://www.google.com.eg/url?sa=t&rct=j&q=&esrc=s&source=web&cd=8&cad=rja&uact=8&ved=0ahUKEwii3Lq D-6fLAhXFWhoKHWxFB-EQFgg1MAc&url=http%3A%2F%2Fburgate-ict.pbworks.com%2Ff%2FTopic%2B4%2B%2BNetwork%2BTopology%2BComparison.DOC&usg=AFQjCNEyB441lLduH1FE7qR6ICVQFHuZPA&sig2=T0lV 8mpu7qc82du1vcgvDA 4- “Advantages and disadvantages of different network topologies” http://www.buzzle.com/articles/advantages-anddisadvantages-of-different-network-topologies.html
