Noted at http://www.tomshardware.com/forum/39940-42-what-teredo-network-connections
For the last month, I have been dealing with Windstream tier 2 and 3 techs to resolve a problem where my latency is not consistent and I have trouble doing anything. Doing tests showed I was getting a constant packet loss rate of anywhere from 5% to sometimes 20-30%. I was going into my NAT settings on my DSL Sagecom 1704 modem and found weird results I'd never ever seen before. Bear in mind I'm on a win XP system that has nothing but Yahoo, ICQ, World of Warcraft and some offline games installed. No Skype.
http://i10.photobucket.com/albums/a146/IxionForte/teredomax_zps8c11bbcf.png
Sometimes I see names with the same address (sometimes a .3 at the end instead of .4) called EA Tunneling and just IP addresses. There you can see Teredo several times. The IP is hard to trace but one site showed me it's located in Kentucky under the name Consiglio Nazionale delle Ricerche. Should I be worried? Is someone tunneling through my system? I have Avast! antivirus enabled and configured properly and ran both that and Malware bytes, then Hijack this! and nothing was really found. I've never had a problem with viruses because I'm aware of how fragile internet security can be, I know what keyloggers and various other malware is and how it works, so I doubt it's that. I've even booted up into safemode and run viral scans with no results. I'm just started to suspect that my latency issues are the result of those tunneling addresses of which I'd never seen before three days ago and I do regularly check my modem settings for things like this.

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