ly controlled world, one many of us may not feel comfortable in. To be fair, there are potential evils of such control, including limited choices, a favoring of the wealthy, and reduced democracy, without a definite guarantee of any more security. There are arguments for both sides of the issue, and you need to be aware of them to ensure open discussion and a voice in the decisions that will ultimately be made. In addition to gaining control, there are other potential benefits for carriers choosing to implement infrastructure based on the ITU next-generation network. Operators implementing that architecture will benefit from the QoS features inher- ent in next-generation networks and will therefore be positioned to give preferen- tial treatment to their own multimedia services as well as have the opportunity to create walled gardens. In so doing, operators can reduce competition by virtue of mediating users' access to applications or content. As discussed in the following sections, the evolving next-generation network infrastructure is composed of several key elements, including IMS, a new three- tiered architecture, a multiservice core, QoS, and an MPLS architecture. Chapter 10 Next-Generation Networks The IP Multimedia Subsystem The architecture of the ITU's next-generation network relies heavily on the IP Mul- timedia Subsystem (IMS) framework. Originally developed by the 3G Partnership Project (3GPP; www.3gpp.org) for 3G/UMTS networks, IMS was based on stan- dards work that started in mid-1999 for an all-IP network. IMS has been extended to cover wireline networks as well, and it now facilitates FMC, eliminating the dis- tinction between wired and wireless networks. (IMS for wireless networks is dis- cussed in more detail in Chapter 16.) FMC speaks to the vision of being able to use one phone with one number, address book, and voicemail bank while enjoying the benefits of low-cost, high-speed connectivity in the office or fixed-line residential environment-of course, still enjoying the freedom of mobility in 