Speed matters on the internet.
Want to order something? Browse, click, pay. Want an answer? Type in a query into a search engine and hit enter. Want to know when your favorite restaurant closes? Find its website, click on it and find the hours.
Prior to the internet, finding information also required patience. But now people demand a response in seconds.
Studies show that if a website doesn’t load within two seconds, users will take their business elsewhere, will not return to the site and will probably tell their friends.
(Lack of) speed kills on the internet.
So let’s say you have a thriving website. You’re getting the point where you have users from around the world. Your single server is fine when it comes to delivering the website to people who are within its general vicinity. But people on the other side of the world, not so much. You know users will avoid slow websites at all costs. You look into what you can do.
One solution to shorten latency times is a CDN, or a content delivery network. A CDN caches static content in servers around the world and delivers it to the user closest to it. These network of servers, or edge servers (because they deliver content “from the edge”, rather than from a singular, centralized server), do a great job in cutting down on latency..
CDN works with DNS, assigning a server to each IP address. Geographic location, and which server to route the traffic to, is done through ISPs. If your DNS query is coming from ISP X, the assumption is made that you’re in this particular geographic area and the information will be delivered from nearby servers set up to deliver content to that ISP. If the query comes from ISP Y, it’ll come from nearby servers set up to deliver content to that ISP it. And so on.
However, this means that users are tied to using the DNS tables of their ISP (or as they’re technically called in this use case, DNS recursors). If they use an outside DNS service, like OpenDNS or Google, their requests will not be routed to the server and cache associated with their ISP.
A traditional CDN is a “dumb” solution. Anycast is a smart solution.
Anycast allows much more flexibility than a CDN paired with DNS. Rather than one IP address paired to a server, an IP address can be mapped to many different servers. This is due to border gateway protocol (BGP – a variation of global internet routing where a one-to-many relationship takes place). Also, the decision of routing which user with what server that’s closest to them is done at the network level — not the DNS level — reducing latency compared to a traditional CDN implementation.
Servers can also be taken offline from Anycast, serviced, then reintroduced with no problems because the magic in Anycast will allow users to go to the next available server. Anycast also offers much more sophisticated load balancing because actual traffic dictates server usage, not ISP usage.
(Can a CDN work with Anycast? Yes, many CDN’s use Anycast technology and that will be the topic of a future post.)
The downside of Anycast? It requires a vast amount of resources (routers, servers, POPs) and is costly to deploy an optimized Anycast network. Anycast requires a fast, reliable global network of data centers, consistent upstream global providers, and a plethora of peering on Internet exchanges (IX).
NetActuate’s network of worldwide data centers put it in a unique position of offering the best Anycast service in the industry. Easily deploy applications on VM’s, bare metal, or bring your own servers for colocation.
But don’t take our word for it. Talk to us. Try it out for yourself. Contact NetActuate and you’ll get a one-on-one consultation about Anycast and our worldwide network of data centers. Contact our sales team to discuss a 30-day proof of concept for your application at firstname.lastname@example.org.