A punishment exerted upon bad, bad internet users by their
ISP's
system administrators. Usually consists of all their incoming and outgoing packets routed to
/dev/null on router level.
If they really want to make your life even more confusing and make the punishment more severe, they'll permit
ICMP packets to go through. That way you can
ping hosts, but can't connect to them. Kinda like Chinese
water-torture for the digital age.