How Does 'Port Forwarding' Speed up My Downloads?

Young man on bed using laptop
MoMo Productions/Taxi/Getty Images

Port forwarding is the redirecting of computer signals to follow specific electronic paths into your computer. If the computer signal can find its way into your computer a few milliseconds quicker, it will add up to be dramatic speed increases for your game or your downloading.

65,536 Paths to Choose From 

That pencil-thin network cable (or wireless network adapter) at the back of your computer contains 65,536 microscopic pathways inside it. Your network cable is the same as a major highway, except your network cable has 65,536 lanes, and there is a tollbooth on each lane. We call each lane a 'port'.
Your internet signal is comprised of millions of tiny little cars that travel on these 65,536 lanes. We call these little cars "transfer packets". Computer transfer packets can travel very quickly (up to thousands of kilometers per second), but they do observe a stop-and-go set of rules, where they are required to stop at each major network intersection as if it were a border crossing between countries. At each intersection, the packet must do three things:

  1. Find an open port
  2. Pass the identification test that will allow it through that port, and if not
  3. Move to the next port and try again, until it is allowed to pass through the toll.

In some cases, packets sent by hackers will be caught and held at the intersection, where they will then be dissolved into random electrons. When this happens, it is called "packet filtering" or "packet sniping."

What Ports Do Computer Packets Like to Use?

Every software in your computer is usually programmed to send its packets through a specific port. These port choices are often established as programming standards in the computer industry. Accordingly, your router needs to be commanded to allow packets through these ports, lest you slow down the speed at which they transfer to/from your computer:

  • HTML pages: port 80
  • FTP file transferring: port 21
  • World of Warcraft: port 3724
  • POP3 email: port 110
  • MSN Messenger: port 6901 and ports 6891-6900
  • Everquest: port 1024
  • BitTorrents: port 6881

Ques: So How Does 'Port Forwarding' Factor Into This?

Port forwarding is when you command your network router to proactively identify and redirect every packet to travel on specific electronic lanes. Instead of having every packet stop at each port in turn until it finds an open port, a router can be programmed to expedite the process by identifying and redirecting packets without having them stop at each port. Your router then acts as a type of hyper-fast traffic policeman who directs traffic in front of the toll booths.
While this electronic identification and forwarding only takes milliseconds, the time involved adds up quickly as millions of electronic packets enter and leave your internet computer. If you program your port forwarding correctly, you can speed up your internet experience by several seconds. In the case of downloading large files, like P2P torrent sharing, you can save yourself hours of download time by programming your port forwards. A song that used to take 3 hours to download can now finish in less than 10 minutes if your port forwards are set correctly.

How Can I Learn How to Program My Router's Port Forwarding Commands?

While the programming of port forwarding can be somewhat intimidating, there are tutorials on the internet that can certainly help beginners. The most common reason for programming port forwarding is to improve the speed of BitTorrent downloads, followed by improving the performance of computer games and streaming media. Towards these ends, there is a splendid resource by the folks at To speed up your specific downloading client, game, or software program: find the exact name of your router and your software, and then visit portforward's website for a visual tutorial on how your router takes port forwarding commands.

Was this page helpful?