orities to applications according to their business needs. In the years that it has been perfecting RSVP, competing QoS standards such as MPLS (multiprotocol label switching) and Diffserv (differentiated services) have evolved. In 2004, Sprint joined AT&T, Equant and MCI (legally known as WorldCom) by offering Multiprotocol Label Switching (MPLS) services to its customers, and seemingly sealed the destiny of the standard as the protocol for next-generation IP networks. MPLS is an IETF initiative that integrates Layer 2 information about bandwidth, utilization, and latency, into Layer 3 (IP) within an autonomous system to enhance IP-packet transmission. MPLS enables network operators to more effectively route traffic around link bottlenecks and failures. It also enables them to apply priorities and preferences in managing diverse data streams, and thereby provide QoS. With MPLS, network operators can sell multiple classes of service with various corresponding price tags. When a packet enters a MPLS network, a label edge router (LER) attaches a label to it that contains routing information such as destination, delay, and bandwidth. The label (often called an identifier) comes with information on the source IP address, Layer 4 socket number information, and differentiated services. Upon completing Video Communications: The Whole Picture and mapping this classification, the router assigns packets to appropriate labeled switch paths (LSPs), in which label switch routers (LSRs) label the outgoing packets. LSPs enable network operators to route and divert traffic based on data-stream type and customer. The Real-Time Streaming Protocol (RTSP) is a streaming-media client/server- oriented protocol that was submitted to the IETF in draft form on October 9, 1996, and was defined by the IETF in RFC 2326 in April 1998. RTSP is an application-level protocol for control over the delivery of data with Real-Time properties. It provides an extensible framework to enable controlled, on-demand delivery of audio and video, whether liv