In simplest terms this is Remote Response time. For instance, you want to invoke a web service or access a web page. Apart from the processing time that is needed on the server to process your request,
there is a delay involved for your request to reach to server and the response from server to reach you.
While referring to Latency, it’s that delay we are talking about. This becomes a big issue for a remote data center which is hosting your service/page.
Imagine your data center in US, and accessing it from India. So there would definitely be some time lag for the request and response to complete. If ignored, latency can trigger your SLA’s. Though it’s quite difficult to improve latency it’s important to measure it
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