ok ive heard with certain providers like clear network aka clearwire and roadrunner and such,that people have problems connecting to home,friendslist,or just the entire network in general

Solution:
Go To Settings>Network Settings>Internet Connection Settings on Ps3
Select Custom settings
Select Connection Method:Wired Or Wireless

ok now set everything to automatic till you get to this option called Dns Setting

Set this to Manual and in both fields in order type these:The DNS addresses are:

208.67.222.222 or/and 208.67.220.220

Once replaced,Finish the Setup and Exit Out
Now you should have no problem logging in.

i am on a 4g Clearwire Modem now,and useing this step i not only have no isses connecting,but the clearwire service is actually bout as fast as comcast now with no hangups