Master Server replies, but nothing will connect

[Sonic]

(reset router) tried several routers, it is surely the xfinity modem settings, but technicians for comcast don't know anything.

alien, 199.83.100.21 assault.cubers.net (or real address of MS)? is there another IP?

1. and 2. in your post go over my head, what to do with R/W rights if i find it? which DNS name or IP name, mine? how ping? sorry for my noobness.