Mr. Yershalmi is the General Counsel for the Center for Security Policy, a non-partisan national security group based in Washington, DC.

CENTERFORSECURITYPOLICY: Center For Security Policy

Bruce Schneier, a security expert and chief security-technology officer at U.K.-based telecommunications company BT Group PLC, said one shouldn't assume that Zappos and Amazon have the same or similar security structures, despite their corporate relationship.

WSJ: Zappos Says Customer Database Hacked