It's a new world. Modern packet-based communications are sweeping away traditional telephony standards and changing the way businesses stay connected. SIP, the latest IP enabler to hit the market, is often portrayed as the key to implementing more sophisticated, flexible voice and unified communications. But is that a fact, or merely well-publicized fiction? This paper explains SIP (also known as session initiation protocol) as well as its background, capabilities and status and then looks beyond the hype and analyzes the relevancy of SIP to today's IP telephony deployments.