Six weeks later, two calls from this number appeared on my call log, but the phone did not ring. They were both listed as the same minute. One showed a VOIP number; the other showed no name. I haven't blocked it myself - yet.
I did the same as lautrec, and purchased a Sentry 2.0 call blocker since Cablevision only blocks 32 numbers.
J2 Global Commu is an annoying caller from Suffolk County selling burglar alarms,when you do pick up phone, by mistake.
For those who posed the questions: chances are that the called ID info has been "spoofed"; in other words, the caller's name and number are falsified to hide the scammers info. Most likely J2Global is just another one of the scammers victims.