Internet Addressing

What are those numbers you told me to put in to reach my Minecraft server?

Well, a Minecraft game session is basically a network service connection. And most network service connections need to know two things:

1. Which server am I trying to connect to, and
2. What specific service on that server am I trying to reach?

This applies to lots of network stuff, like email, web connections, and whatever else the Internet is used for. Seriously, web and email cover 99% of it now, anyway.

The first item above is either an IP address (a bunch of numbers) or a host name (like www.minecraft.net). People work better with names, so web browsers and email clients let you put in the host name instead of making you type in a bunch of numbers. But in most cases, either one will work.

The second item is a port number. Many times, the port number is implied by what we are trying to do. Web browser traffic, for instance, is almost always going to port 80, which is the standard port for the HTTP network service. For sending email, our email client knows to use port 25 for the SMTP network service.

When we need to give both parts, I mean when we need to give the port number in addition to the host name or IP address, we put a colon after the first part and we add the port number. There shouldn't be any spaces or anything else in there.

For example, our Minecraft server address is 192.168.1.22:25565

And to reach my blog, you can enter grassrootslearning.blogger.com:80 in your browser's address bar. The ":80" isn't needed, but it works.

Here are some topics for further reading:

• How are host names made up?
• Commonly used port numbers
• IP Networks and Subnets
• IP Routing
• Dynamic Name Service (DNS)
• Dynamic Host Configuration Protocol (DHCP)