Factors that affect the performance of networks
A group of interconnected computers/devices. performance is about response time - how fast a message can be sent or how quickly a document can be retrieved. The performance of a network can be affected by various factors:
- the number of devices on the network
- the Bandwidth measures the amount of data that can transfer through a communications channel over a given period of time. of the How data is carried from point A to point B physically, either by cable or wirelessly.
- the type of network Communications sent over a network.
- network A period of time delay in a computer system.
- the number of The sending of data from point A to point B. errors
Any network can be affected by one or a combination of these factors.
Bandwidth
Bandwidth measures the amount of data that can transfer through a communications channel over a given period of time. is a measure of the amount of Units of information. In computing there can be different data types, including integers, characters and Boolean. Data is often acted on by instructions. that the medium can transfer over a given period of time. Each transmission medium has a different bandwidth:
| Medium | Typical bandwidth |
| Twisted copper wire | Up to 10 gigabits (Gb) per second |
| Fibre-optic cable | Up to 100 gigabits (Gb) per second |
| Wi-Fi (home networks) | Up to 600 megabits (Mb) per second |
| Business Wi-Fi | Up to 6 gigabits per second |
| Medium | Twisted copper wire |
|---|---|
| Typical bandwidth | Up to 10 gigabits (Gb) per second |
| Medium | Fibre-optic cable |
|---|---|
| Typical bandwidth | Up to 100 gigabits (Gb) per second |
| Medium | Wi-Fi (home networks) |
|---|---|
| Typical bandwidth | Up to 600 megabits (Mb) per second |
| Medium | Business Wi-Fi |
|---|---|
| Typical bandwidth | Up to 6 gigabits per second |
Each connected device requires bandwidth to be able to communicate. The bandwidth of the medium is shared between each connected device. For example, a home A method of connecting to the internet wirelessly using radio waves. network with one device would allocate 54 Mb per second to that device. If a second device joins the network, the bandwidth would be split between the two, giving 27 Mb per second to each, and so on. If ten devices were connected, the bandwidth allocated to each device would drop to 5.4 Mb per second, thereby reducing the rate at which data can be sent to any particular device.
In reality, however, things are more complicated. Different types of network traffic usually have different bandwidth requirements. For example, streaming a high definition video requires more bandwidth than streaming a low definition video. Some network switches are capable of determining the type of traffic and adjusting the bandwidth allocated to a particular device to accommodate the traffic's requirements.
Latency
Network latency is a measure of how long it takes a message to travel from one device to another across a network. A network with low latency experiences few delays in transmission, whereas a high latency network experiences many delays. The more delays there are, the longer it takes to transmit data across a network.
Latency is affected by the number of devices on the network and the type of connection device.
A A piece of hardware used in computer networks used to connect multiple devices.-based network will usually experience higher latency than a A device for connecting computers and other network capable devices together to form a network.-based network because hubs broadcast all messages to all devices. Switch-based networks transmit messages only to the intended recipient.
The greater the number of devices connected to a network, the more important the choice of transmission medium becomes. Wi-Fi generally handles less traffic than twisted copper wire (TCW), which in turn handles less traffic than Cable that carries data transmitted as light.. Many networks include a combination of all three media:
- fibre-optic cables allow high data transmission between different buildings
- TCW runs from switches within buildings to individual devices
- Wi-Fi allows guest devices to connect to the network
Transmission errors
Inevitably there will be times when devices try to communicate with each other at the same time. Their signals collide with each other and the transmission fails. It is similar to when two people speak to each other simultaneously - neither person is able to clearly hear what the other person is saying.
The greater the number of devices on a network, the more chance of a The result of two devices on a network trying to communicate with each other simultaneously. occurring, and the longer it takes to transmit a message.
