I'm glad someone finally said this again for some people. Particularly the part in bold. I always get an entertainer buff for my NIC when I go to play.
Packet loss is something that happens in any MMO due to the protocol used for network traffic. UDP is a protocol used for MMO's because it doesn't need confirmation of packets on arrival. Server will transmit packages to you and the result you see on your client is a result of the packets received/sent. If confirmation was used, the game would be running considerably slower due to the higher amount of network traffic required. Every packet would need confirmation of arrival.
Packet loss should be at 0% at all times. If it isn't you should reset the path to the server by resetting your network adapter or router. Failing that, reboot the PC. If that still doesn't work, run a pathping to locate the problem. Somewhere along the line you'll get an error.
Using pathping from the command prompt will poll the entire path for a period of 225 seconds, giving a much better indication of the route and the problems it may have. Once % drops below 100%, thats where the problems are located.
Packet loss is not Server Lag, it can be equally frustrating though because your toon can be dead on arrival.
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