Have you ever been on the internet and found one website or one server in a game to be particularly slow, but the rest of the internet was fine? That may be an example of a routing problem, where the problem in your connection is not something within your household, but something along the chain between your home and the server you're connecting to. Internet routing is an often overlooked crucial part of the internet's infrastructure, and you'd be surprised how much it can actually influence your internet experience.

How internet routing works

The technical explanation

When you're using the internet and communicating with servers all around the world, the data that you send is broken down into "packets". Each packet includes the data and metadata, such as the source and destination IP addresses. Routers, which are devices that direct these packets, play a crucial role in this process. They are connected to multiple networks and use routing tables to decide the best path for each packet. These use protocols to share information about network topologies, and these protocols include:

• BGP (Border Gateway Protocol): Used for routing between large networks
• OSPF (Open Shortest Path First): Used within large networks to find the best path based on link states
• RIP (Routing Information Protocol): An older protocol that uses distance vector algorithms

These routers rely on routing tables, which store routes to various destinations. When a packet arrives at a router, it checks its routing table to determine where to send the packet next. The path selection process involves evaluating multiple routes based on factors like distance, speed, cost, and reliability to find the most efficient path. When a router is first connected to a network, it will build an initial routing table based on the information that the routing protocols it uses receive. This means building up a network of all the devices on the same network and immediately external to the network, such as your ISP's routers.

Once configured, routing protocols will calculate the best paths based on their specific algorithms and metrics. These best paths are then added to the routing tables. For instance, OSPF uses link-state information to determine the shortest path, while BGP uses policies and attributes to select paths between autonomous systems. An autonomous system in networking is a collection of IP networks and routers under the control of a single organization that presents a common routing policy to the internet.

However, BGP relies on trust and has been abused in the past. For example, in 2008, the government in Pakistan tried to ban YouTube. Pakistan Telecom used BGP to route YouTube's address block into a black hole. This was then transmitted to Pakistan Telecom's upstream provider, PCCW Global, and was then distributed globally. This meant all YouTube traffic got briefly re-routed to a black hole in Pakistan as a result.

Why internet routing can mess up your connection

It's a hard problem to solve

With a basic understanding of routing in mind, you can visualize your connection to a server as a series of "hops." These hops represent the steps your packets take as they transfer across the internet. You can visualize this process on your computer through a traceroute, which will show you every connection the packet you send goes through on its way to its destination. Proper routing helps protect data integrity and privacy, with secure routing practices preventing attacks such as IP spoofing, route hijacking, and denial-of-service attacks.

However, sometimes routing can cause problems, even if it's rare. That's why VPNs like Exitlag exist, aimed at gamers and ensuring that latency is as low as possible. I've experienced this when playing games online, where my latency would spike and remain high for a period of time, despite my internet generally being fine. A traceroute in those instances would reveal a problem somewhere along my connection, typically within a router controlled by my ISP. In those cases, you can essentially "force" another route by using a VPN, which is the philosophy behind tools like Exitlag.

Content Delivery Networks (CDNs) also use advanced routing to deliver content from servers close to users, reducing load times. They often have servers containing the same data in different areas of the world, so you can be close to a copy of the data you need to access at any given time. This ensures reduced latency based on distance and less complicated routing. If you're trying to connect to a game server and a hop in the middle has a poor connection, you'll face a diminished experience with no way to improve it on your own. VPNs in general will change your routing, but Exitlag is aimed specifically at gamers so that you have as little increased latency as possible.

Next time you're having internet problems and can't figure out if it's your internet or something outside of your connection, use traceroute to try and find out more.