Maybe a stupid question, but is this on the PC?
Whats your subscribed net speed, what is the speed your actually getting, make sure your not being throttled/bottle necked by the isp. Have you tried calling Tech support from your ISP?
Hundreds of thousands of people play this game online without a problem and are able to connect to the servers with no issue at this point everything you have said leads me to believe its your network and not the game servers at fault.
Your best bet is your ISP tech support.
Do you use a virus scanner (AVG)? Google that issue with BF3.
Have you manually updated PunkBuster? (and reset the PC after it)
Is more than one person trying to access the same server from the same LAN? Have you checked the required port settings?
Have you tried disabling UPnP?
I am not experiencing that issue.
I wish my grass was Emo, then it would cut itself!