Made for Speed: Precious Pointers on Port Forwarding

computer network

Sometimes a few milliseconds can add up to a much larger amount of time, particularly when information is traveling over a network. When downloading large files, working with real-time data, playing games, or doing any activity in which time matters, changes to the port forwarding process can make the difference between a fast experience and agonizing wait times. Port forwarding can also allow you multitask over a network without slowing down any of the applications you are using. Here is how it all works.

computer network

What Is Port Forwarding?

Port forwarding, also called port mapping, is actually a collection of three processes. To understand how the processes work, one must understand what packets are. When someone wants to send data over a network, three things are needed:
.   an origin address (where the data came from),

.   a destination address (where the data is going), and

.   the data itself.

Most files are too large to send in one single chunk, so they are instead broken into smaller pieces called packets. Each packet contains a piece of the data, an origin address, a destination address, and a count that tells a computer what number packet it is out of the total. These packets are sent over a network by bouncing from one “node” to the next.

A node is just a piece of hardware, like a router or a sever, that can deal with packets. You can think of nodes like post office branches that accept packets (the letters) and read their addresses to get them to the right destination. Port forwarding is the process that each node uses to determine where to send a packet. The process consists of
.   translating the address of the packet (called the port number) to the next destination in the route the packet is taking to its final stop,

.   deciding if a packet is safe to send on or not (firewall function), and

.   forwarding the packet to its next node (or it’s final destination).

Port forwarding allows remote computers to share information with one another, but there are some interesting caveats to the process. Most importantly, there is always more than one way to get information from its origin to its destination. In other words, information can use more than one port to get where it needs to go.

Most of the time, software handles the selection of ports automatically and most people never think about changing anything. It is possible, however to select ports manually. Manually selecting a port can help speed up the transfer of packets over a network, shaving milliseconds off of the transfer time of a single packet. That may not seem like a lot, but consider that an average packet is only a few hundred bytes in size. If you had to send a file that was 1 GB in size, then you would have to send thousands of packets. Shaving a few milliseconds off of the transfer time for each one of those packets could save you a lot of time.

Port Forwarding Tips to Improve Speed

Forwarding a port requires that you know the IP addresses of your PC and your router. When you know those, you log in to your router and use its built-in port-forwarding functions to make changes. This usually consists of telling the router what applications you want forwarded (bit torrent downloads, VOIP (like Skype), games, etc.) and then giving those programs permission to get through the router’s firewall. Here are a few tips for making port forwarding really work well.

.   Give each Internet application its own port. For instance, give your bittorrent client such as Vuze one port, Minecraft another port, and your favorite Internet browser yet another.

.   Ensure the port you choose isn’t blocked by your ISP.

.   Test the port to see if it works and run a speed test to see if one port is faster than another.

.   Pick good hosts or torrents to ensure they don’t bog down your system.

Port Forwarding Wrap Up

Even if you aren’t a power user, port forwarding can still make your life more pleasant by allowing you to multitask like never before. If you set up your ports properly, you can use Skype while browsing the Internet and playing Minecraft. Your computer can handle the work, you just have to adjust port settings to get the most out of its CPU.

Grace Munson is a file sharing and managing maven. When she has free time, she likes to share what she has learned by blogging online.