Can someone please enlighten me why while playing online games (Diablo 3), my connection will fail in the middle of a quest.

The same thing happened last night. However, it does not happen every night.
Upon closer inspection, there is a red led light on my netgear router. I guess it could be an authentication problem. After switching the router off/on all the lights are green again!
I have done a tracert but it seems fine.
Can it be a fault with my router? I'm on a 1mb Gold Leon edition account.
C:\>tracert
www.google.com
Tracing route to
www.google.com [74.125.233.83]
over a maximum of 30 hops:
1 <1 ms <1 ms <1 ms 192.168.0.1
2 10 ms 10 ms 9 ms 196-210-147-1.dynamic.isadsl.co.za [196.210.147
1]
3 10 ms 11 ms 11 ms vlan2473.cdsl2-ctn.isdsl.net [196.38.72.193]
4 10 ms 11 ms 12 ms 196.35.115.136
5 11 ms 12 ms 11 ms 168.209.2.12
6 31 ms 32 ms 32 ms 168.209.100.13
7 32 ms 56 ms 32 ms 196.26.0.130
8 32 ms 33 ms 34 ms 74.125.49.66
9 32 ms 33 ms 32 ms 64.233.174.57
10 32 ms 33 ms 33 ms jnb01s02-in-f19.1e100.net [74.125.233.83]
Trace complete.