IP to a scenario where IP runs on OTN or even ION. However, this transi- tion assumes that metropolitan area service providers (MASPs) and long- haul service providers will offer affordable lambda services to end users. In 2001, we saw an unfortunate shrinkage in the number of carriers offering alternative, high-end, and innovative services. If carriers don't provide these services, the promise of ION and GMPLS could only be realized over private optical networks, which are cost prohibitive for nearly all end users. ION presents the carriers with a number of prima facie benefits: Switching lambdas is cheaper than switching packets and gives users better QoS and throughput. It eliminates costly O-E-O conversions. All-Optical Networks Figure 7-5 Evolving protocol stack showing ION GbE MAC 10GbE MAC RPR MAC DS0/DS1/DS3 10GbE WAN PHY SONET GbE LAN PHY 10GbE LAN PHY Intelli gent Optical Networking Fiber It cuts down equipment while consolidating systems and network infrastructure. Furthermore, there may be flexibility and management advantages in good implementations, such as just-in-time provisioning, point-and-click service provisioning, and traffic engineering at the lambda level. For those buildings in the United States with fiber facilities, revenue opportunities reside in fast-provisioned, bandwidth-on-demand lambda services and OVPNs. See Figure 7-6 for a graphical example. SONET/SDH and Ethernet private-line services can be supported with ION. Architecturally, ION enables the gradual and seamless adoption of new technologies into the network and supports the migration to mesh net- works. In contrast to dark fiber and unprotected WDM, it provides access to protection bandwidth. Developers designing ION capabilities have to focus Chapter 7 Access Ring 2 Figure 7-6 OVPN. Access Ring 1 Access Ring 4 Access Ring 3 BONE = Backbone Optical NE EONE - Edge Optical NE on carrier-class services, however, because that's what customers have tended to demand. The customers want Network autodiscovery Availability Reliability