ffered great flexibility and the ability to work around congestion and failures, but at the expense of delays. We are moving to a connection-oriented envi- ronment where we can predefine the path and more tightly control the latencies, using techniques such as Frame Relay, ATM, and MPLS, each of which allow us to separate traffic types, prioritize time-sensitive traffic, and ultimately reduce access costs by eliminating leased-lines connections. The other main effort in redesigning the Internet core is that we are increasing the capacity, moving from OC-3 and OC-12 (155Mbps and 622Mbps) at the back- bone level to OC-48 (2.5Gbps), OC-192 (10Gbps), and even some early deploy- ments of OC-768 (40Gbps). But remember that the number of bits per second that we can carry per wavelength doubles every year, and the number of wavelengths that we can carry per fiber also doubles every year. So the migration beyond 10Gbps is also under way in the highest class of backbones, and it will continue with the The Organization of the Internet evolution and deployment of advanced optical technologies. (However, to be fair, there are issues of power consumption and customer demand to deal with, which will ultimately determine how quickly what is technically feasible gets adopted in the marketplace.) The emergent generation of Internet infrastructure is quite different from the traditional foundation. It is geared for a new set of traffic and application types: high-speed, real-time, and interactive multimedia. It must be able to support and guarantee CoS and QoS. As discussed in Chapter 9, it includes next-generation telephony, which is a new approach to providing basic telephony services while using IP networks. The core of the Internet infrastructure will increasingly rely on DWDM and optical networking. It will require the use of ATM, MPLS, and Generalized MPLS (GMPLS) networking protocols to ensure proper administration of performance. (Optical advances are discussed in Chapter 11, "Optical Networking.") New gener- ations of IP p