nsagate.apple.com

Also it could be "Next Step Administration", "Next Step Access", etc.. there are a billion possibilities, I'm not saying apple doesn't give access to NSA, they surely do, but I'm saying they obviously won't do it this way ;)

"In computer networking, port knocking is a method of externally opening ports on a firewall by generating a connection attempt on a set of prespecified closed ports. Once a correct sequence of connection attempts is received, the firewall rules are dynamically modified to allow the host which sent the connection attempts to connect over specific port(s). A variant called Single Packet Authorization exists, where only a single "knock" is needed, consisting of an encrypted packet.[1][2]

The primary purpose of port knocking is to prevent an attacker from scanning a system for potentially exploitable services by doing a port scan, because unless the attacker sends the correct knock sequence, the protected ports will appear closed."

http://en.wikipedia.org/wiki/Port_knocking