random blizz person posted:

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Here are the most common causes of high pings/latency (on both Home and World):


1) Wireless

2) Packet loss

3) Almost-but-not-quite-broadband*

4) Addons (yes, those wonderful UI modifications)

5) Firewalls (some firewalls do interesting things to latency... try playing without it to see if it helps!)

5) Mis-configured or defective home routers (please temporarily bypass before anything else)

6) Quality of Service and Traffic Management Systems performing packet queuing of some sort.

7) Net link saturation (not necessarily your ISP, but somewhere between you and Blizzard)

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