PS3 DNS Error 80710102 FIX
Occasionally my PS3 refuses to sign in. After trawling through a billion pages I finally found the solution.
Change your DNS servers to 220.127.116.11 or/and 18.104.22.168
All the other settings don’t really make any difference. My router was even set up to put the PS3 in DMZ (Demilitarised Zone) which didn’t help at all. The fault really lies with your ISP, apparently. My original DNS was 22.214.171.124 and 126.96.36.199.
Thanks to amstel78 from the PSN forums.