Lowering latency (ping) times

Many things can affect your latency (the amount of time it takes for information to travel from your computer through the internet, to Blizzard's servers) in-game; wireless connections, your ISP (internet service provder), various server nodes belonging to "backbone" service providers such as Level3 Communications, Mizima, and even AT&T experiencing temporary issues.

A common misconception is that if your latency is high, it's the fault of Blizzard. This is normally not the case, as Blizzard is the destination, and they have as much control over how the internet works as you yourself do. The general indication as to whether its Blizzard or your or your connection to Blizzard, is if all other users on your server are experiencing issues. Then and only then is the problem going to be on Blizzard's end. Remember, speed does NOT equate to latency. Speed refers to how quickly you can download something. Latency refers to the length of time it takes a packet to travel from Point A to Point B.

Fixing Latency
There is a small program that you can download and run called the Leatrix Latency Fix, that changes a setting in your registry to change the way your system handles information packets. North American users can usually go from ~300ms to about~120ms, while Pacific users can get down to about ~300ms in good circumstances. You can find the program here: Leatrix Latency Fix. Allowing this program is safer consider there is an option to reverse the changes, and its 100% safe for users who aren't computer savvy enough to touch the registry.

Manual Fix
If however you are computer savvy, and are comfortable doing manual registry edits, you can manually change the settings by doing the following (source: http://www.speedguide.net/read_articles.php?id=158)


 * Disabling "nagling" allows for very small packets to be transferred immediately without delay. Note that is only recommended for some games, and it may have negative impact on file transfers/throughput. The default state (Nagling enabled) improves performance by allowing several small packets to be combined together into a single, larger packet for more efficient transmission. While this improves overall performance and reduces TCP/IP overhead, it may briefly delay transmission of smaller packets. Keep in mind that disabling Nagle's algorithm may have some negative effect on file transfers, and can only help reduce delay in some games.


 * To implement this tweak, in the registry editor (Start>Run>Type "regedit" Hit enter) find:


 * HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\Interfaces\{NIC-id}
 * There will be multiple NIC interfaces listed there, for example: {1660430C-B14A-4AC2-8F83-B653E83E8297}. Find the correct one with your IP address listed (to easily find your current IP, you can visit Whatismyip.com.
 * Under this {NIC-id} key, create a new DWORD value:
 * TcpAckFrequency with the value being 1
 * (DWORD value, 1=disable, 2=default, 2-n=send ACKs if outstanding ACKs before timed interval. Setting not present by default).

Close and save your registry, then restart your computer.

Tunneling Services
Many players that aren't in North America are finding they're able to lower their latency by using a tunneling service. While not prohibited, Blizzard does not support the use of a tunneling service. In fact, many are finding their accounts locked as a result. This isn't because they're using a tunneling service, but rather due to how the tunneling service works. Tunneling attempts to find the quickest route to the game server, often changing IP addresses very quickly from various points around the world. This flags the security routines built into the system and flags the account as a possible compromised account.

While it's possible to unlock the account to play, you'll need to work with your tunneling service company to find a way to minimize the service's effect on your game play. If you select the best server and stick with it, you may find your account lockouts may diminish.

Packet Shaping
The Windows version of traceroute will not always show there's an issue with your connection. The reason for this is traceroute sends the packets using ICMP (Internet Control Message Protocol). This is a special set of instructions designed to query for errors on the network. And with the Windows version of traceroute, you can't specify the port you wish to trace to. Bear in mind, just because you have a good trace to the server, doesn't always mean that everything is fine. Your ISP could be using packet shaping on port 3724 which will kill your latency to the realm server. Packet shaping is used for a few reasons, the primary reason being bandwidth throttling. By using packet shaping, an ISP can allow unfettered access to webpages via port 80, yet delay the connections on port 3724, resulting in extremely high latency in game, and trace after trace will look just fine.

Most ISPs won't tell you if they're using packet shaping (although some university campus IT departments will). Comcast was one of the most recent providers caught doing it, although they vehemently denied it. It's rumored that some Australian providers also use packet shaping.

University Networks
Many universities have locked down the required ports needed for game play due to file sharing issues. Many are under the misconception that they must lock these ports down, or face loss of federal funding. This is not the case. The Digital Millennium Copyright Act and the Higher Education Opportunity Act require universities to actively seek out and punish those who participate in illegal file sharing practices. However, instead of doing that, many campuses just block all peer to peer ports in an effort to comply with the law.

And even though the ports may be open, they may enforce packet shaping on them. This will result in higher than normal latency between you and the realm servers. And this practice isn't limited to just campus networks. Some ISPs have been known to utilize packet shaping as well. The problem is, you can't determine if this is the case by a simple traceroute (unless you're using Linux). ICMP packets are sent differently and are usually allowed unimpeded through the network (although some campus networks will block ICMP packets as well).

About the only thing you can do is approach your campus IT department and inquire if they use packet shaping. If they do, Blizzard will work with them to open the required ports for traffic destined to the realm servers, while leaving the rest of the packet shaping intact for all other traffic. Some IT departments are open to doing this, others are not. Your mileage may vary.