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How Latency affects the Bandwidth


I am confused about the role latency plays while carrying traffic.

How does it affect the the speed on port (ex. 1gbps switch port)

Kindly explain.


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The short answer is nohow.But

The short answer is nohow.
But in fact it affects trueput, If you have a tube with a radius of one meter, you can push particualr amount of water into it, but if the wind is blowing from the other end, the water will reach that end slower, then in a similar tube with no wind.


Because round trip time is

Because round trip time is one of the factors used in calculating throughput - higher latency = lower throughput. This link gives a great explanation:

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It doesn't impact bandwidth, per se, but many protocols send some amount of data then wait for an ACK before sending more.  Latency very much impacts how long the sender pauses between transmissions.

A wonderful example often is using TFTP on WAN to two different locations, when available bandwidth is the same, but latency is very different.  The site with the lower latency will transfer data faster as the pause between transmissions of packets is shorter.

Some protocols don't wait on ACKs, e.g. VoIP, so from a bandwidth perspective, latency doesn't matter (although if there's enough latency, people will notice - ever talk, on a phone, via satellite?).

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