Cloud Architecture Patterns

Chapter 11. Network Latency Primer

This basic primer explains network latency and why delays due to network latency matter.

The time it takes to transmit data across a network is known as network latency. Network latency slows down our application.

While individual networking devices like routers, switches, wireless access points, and network cards all introduce latencies of their own, this primer blends them all together into a bigger picture view, the total delay experienced by data having to travel over the network.

As cloud application developers, we can decrease the impact of network latency through caching, compression, moving nodes closer together, and shortening the distance between users and our application.

Network Latency Challenges

Highly scalable and high performing (even infinitely fast!) servers do not guarantee that our application will perform well. This is due to the main performance challenge that lies outside of raw computational power: movement of data. Transmitting data across a network does not happen instantly and the resultant delay is known as network latency.

Network latency is a function of distance and bandwidth: how far the data needs to travel and how fast it moves. The challenge is that any time compute nodes, data sources, and end users are not all using a single computer, network latency comes into play; the more distribution, the greater the impact. Network quality plays an important role, although it is one you might not be able to control; quality ...