[ad_1]
Effective bandwidth is the actual speed of data transmission, which is often lower than the theoretical maximum due to factors such as distance and packet delays. Broadband providers limit total bandwidth to balance demand and cost, resulting in slowdowns during peak times.
Effective bandwidth is the actual speed at which data can be transmitted over a connection. This is in contrast to the theoretical maximum that the connection can carry. Originally effective bandwidth was used in reference to dial-up devices, although the term can also be used for persistent connections such as broadband Internet providers.
An example of limited effective bandwidth is with home broadband services. Each customer connected to a local PBX will be given a maximum possible speed that is available on their connection. However, if every customer connected at this speed at the same time, the amount of bandwidth going through the local exchange would be very, very expensive to provide. This is highly unlikely to happen, so the connection isn’t configured for it.
Instead, your broadband provider or local carrier will limit your total bandwidth. The limit chosen will be a balance between the higher demand it expects to receive and the desire to keep costs low. This usually means that there will be situations, such as at peak times, where the total bandwidth requested by customers exceeds what has been made available. This means that customers will experience slowdowns and their effective bandwidth will be significantly slower than their maximum bandwidth.
However, there are many other reasons beyond artificial limits why an actual bandwidth may be less than the stated maximum. The simplest is that data will be slower to transfer if it has to travel further. This can mean that actual bandwidth varies between users in different locations.
Another problem is the way data is sent in packets. These are small batches containing part of the data being sent, plus information to identify the sender and recipient, and an error checksum, which is the mathematical equivalent of a checklist to make sure the data has arrived safely. At each intersection in the data path around the network, the entire packet has to arrive before it can be inspected and then routed on to the next stage of its journey.
The delay between the first part of the arriving packet and the last arriving part slows down the overall speed. This means that the actual bandwidth is inevitably slower than the theoretical maximum. There is also the possibility of delay when two or more packets arrive at the same gateway at the same time, meaning they actually have to form a queue, also known as a buffer.
[ad_2]