All for one or any for all: a guide to unicast vs. anycast routing

There’s something to be said for keeping it simple, and that something is that keeping it simple is always the best policy…that is, when you’re the one in charge of configuration. When setup and maintenance is someone else’s responsibility, there can be definite benefits to letting things get a little complex. Such as in the case of the optimal routing for your website’s performance.

What it’s all a-rout

Simply put, routing is the process of establishing the path of traffic in a network. In terms of a website, it’s the process of connecting users to the desired website and to the specific pages and files contained therein. This relay of data is accomplished through what is known as network topology, or the setup of hardware such as routers. These pieces of hardware are called network nodes, and they are capable of creating, transmitting and receiving data.

There are different routing configurations, of course. Since routing delivers traffic to your website, routing optimization is a major factor in website performance, and this is why it’s so essential to know the difference between unicast and anycast.

Keeping it simple

The unicast routing setup is simple: every network node has its own IP address, and any request to that IP address goes to that network node no matter where in the world the request is originating from or where in the world the node is located. It’s communication in which there is one sender and one receiver.

Think of it like ordering a product from a farm in Scotland. As a small business, they were in charge of setting up their own shipping and handling, so whatever it is that you purchased there is going to ship from that farm in Scotland no matter where in the world the buyer is located and how long it will take to arrive.

Most of the internet uses unicast routing. Not because it’s the best, but rather because it’s the easiest, and for many people setting up their website’s routing, that’s what matters most.

Getting a little complex

Anycast routing is a routing configuration in which a single IP address is advertised by a number of network nodes, which makes any of those nodes a valid recipient of a request to that IP address. The node that receives the request is the one closest to where the request originated, since reducing the geophysical distance that data has to travel is a major part of reducing latency and speeding up a website’s performance.

Think of this one like ordering from Amazon, one of the world’s largest corporations with distribution centers all over the world. Your order is going to be directed to the distribution center closest to you, and that’s where it will be shipped from. This configuration ensures the fastest possible service.

Anycast easily outperforms unicast – and if all aspects, including setup and maintenance, were equal – certainly more websites would use it. Especially considering that studies have shown that most online shoppers will only wait five seconds for a web page to load. However, anycast routing is a complicated configuration.

Getting the benefits of anycast without the hassle

Not only does anycast routing provide faster website performance for a website’s users all over the world, but due to the nature of its configuration it also offers built-in load balancing and some measure of protection against DDoS attacks. For many website owners, this all adds up to an important question: how can I get it?

The easiest way to get anycast routing performed on a worldwide scale is to procure the services of a Content Delivery Network, or CDN. A CDN is essentially what it sounds like – a network designed to get your website’s content to your users as efficiently as possible through a combination of front-end optimization, caching and network level performance enhancements (such as anycast routing). CDNs also provide the aforementioned load balancing as well as DDoS protection, and some leading CDNs offer full DDoS protection on top of the inherent protection of the multi-node environment.

Perhaps best of all, a CDN is a managed service, which means anycast routing and every other benefit associated with the use of a CDN is taken care of by a company that specializes in it. If you’ve been keeping track, that’s the perfect situation for allowing things to get complex.