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*click*Najena*click*
First, our computer locates the address for the Najena Server in DNS as address 199.108.12.65. Then, our computer sends a message to that address on a pre-determined port stating that we wish to enter. The Najena Server will confirm that we’ve already been through “ServerLogin” and “ServerPatch” and will determine where our character is in the world. The Najena Server will then provide our computer with an address of a different server to communicate with to get access to our character.
It’s best to imagine each “World” like a row of computers all lined up with one single computer sitting in front of the row. That single computer in the front is the World Server. In our example, this would be the Najena Server that we looked up in DNS. Each of the computers in the row behind the Najena Server represent different parts of the “world” we connect to. When we contacted the Najena Server requesting access, after it performed its verifications, it determined on which of the servers in the row our character was located and that is the address that was provided back to our computer.
Remember how this all started? Standing at the gates of the Thundering Steppes, ready to conquer lands un-seen.. Then we opened that blasted gate only to be yanked back into the reality of life… When we opened that gate to venture forth, what happened? “Behind the scenes” we moved from one server in the row mentioned above to another one in that row. Moving from one server to another means another address, and yes, yet another rule for our firewall.
As you can imagine, with the size of the worlds in MMORPG’s today, each world must be run on many different servers. In fact, if we checked out the support site of the game we were trying to play, we would see that the world servers consist of many groups of addresses. We would need to permit our computer to be able to communicate to every address in each group to ensure we don’t lose connection like we did when we tried to enter the Thundering Steppes! Fortunately for us, there’s an easy way to identify a group of IP Addresses to our firewalls. That easy way is using something called a “netmask”. This concept can be confusing, so to explain this concept, we’re going to compare an IP address to a more common message delivery device: a telephone. Let’s take the phone number (212) 555-1234 for our example here. When we look at a telephone number, we can break it down into 3 independent parts:
- The area code: (212)
- The prefix: 555
- The unique number: 1234
We know that the area code correlates to which state that number is located, in this case the 212 area code is in New York. The prefix narrows that down to a town or a county, “555” is only used in movies, but let’s pretend for this example 555 is Manhattan. The last 4 unique digits of the phone number correspond to a specific phone in Manhattan, NY. Many other people who live in Manhattan, NY have a phone number which starts with (212) 555, but our example phone number is the only one with the unique 4 digits of 1234. So, (212) 555 can be used to identify a group of phone numbers in Manhattan, NY. Now, let’s create a “netmask” for all of the phones in Manhattan, NY. We will use a “9”, the highest number on the telephone, to represent the part of a phone number which tells us the number is in Manhattan, NY and we use a “0”, the lowest number on the telephone to identify the part which is unique for each phone. So, our “netmask” may look something like this: (999) 999-0000. However, this is not just a “netmask” for phone numbers in Manhattan, NY, is it? Phone numbers which start with (206) 441 are all in Seattle, Washington, so they would have the exact same “netmask”! How do we just specify numbers in Manhattan, NY? We need a combination of any single telephone number in Manhattan, NY and a “netmask”. So, the phone numbers in Manhattan, NY can be identified with a phone number of (212) 555-0000 and a “netmask” of (999) 999-0000. A “netmask” for computers works in much the same way. For an IP Address, “255” is the highest value that each part of the address can be and “0” is the lowest. Just like in the telephone example, if we wanted to create a “netmask” for all of the IP addresses which match 199.108.12.*, it would look like this: 255.255.255.0. By using a combination of an IP Address, 199.108.12.0 and this “netmask” of 255.255.255.0, we can successfully identify all of the computers that have an IP address of 199.108.12.*. There is a deeper, more complex explanation of “netmasks”, however, for the needs of the masses of MMORPG players, I think this explanation is sufficient enough to write the rulesets on your firewalls and get up and running in no time.
Ok, let’s sum up what we have so far:
- We need a rule set in our firewall to connect to “ServerLogin”
- We need a rule set in our firewall to connect to “ServerPatch”
- We need rule set(s) in our firewall to connect to the “GameWorld” Servers.
If you remember these three items here, they will save you hours of grief and banging your head on the wall. For 98% of all MMORPG’s, these are the 3 rules you will always need to add to your firewall. If you add these right from the start, you will minimize about 95% of your firewall connection issues immediately.
There’s one more thing we should mention before you go running off with your newfound knowledge ready to impress the magnitude of other gamers out there. When you start to do your search on your gaming site to locate the address and port information you require, you may see them refer to things such as TCP and UDP. These two items are “protocols”, which in common language translates to the way the computer delivers the message to another computer. The simplified way to differentiate between the two is this; TCP is “guaranteed delivery”, like insuring mail when you send it out. It’s guaranteed to arrive at the destination. On the other hand, UDP is “send it and forget it”, akin to slapping a stamp on your message, dropping it in a mailbox and hoping it makes it to its destination. As you know with today’s mail, normally it does make it there, however there’s always the chance that it gets lost in the mail system, never to be seen again. The only real thing you need to know about these two “protocols” is that when you are setting up your rules in your firewall, you may need to specify which protocol the rule is for. Just make sure you choose the protocol that is specified by the company who produced the game and you will be good to go.
Well, I hope this article has given you some insight as to what actually goes on “behind the scenes” and helps your to better prepare your computer and firewall before journeying forth to discover those new frontiers.
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