e total service cost? Is the cost in the protocol engine or is it in the physical fiber link from the building to the metro core network? Figure 4-8 provides a hint and subtext for equipment manufacturers. The figure implies that a mere cost reduction in the edge network element (even at a Next-Generation SONET and Optical Architectures Figure 4-6 Next-generation SONET system- STDM trunk. Transport Bandwidth Channel Assignment Switch Matrix Transport Bandwidth Scaling Layer 2 Switching Priority Queuing Priority Queuing and Flow Control Exiting Data Entering Packets Data Packets Traffic Tunneling (Packet Encapsulation) Ethernet Ports 100 percent rate), either because the price of the SONET NE is reduced or because it eliminates a supplemental bridge/router at the customer build- ing, only has a 6 percent impact on the total monthly recurring charge (MRC) cost to provide transparent LAN service (TLS) to 4 customers in a building. On the other hand, if the new technology can reduce the opera- tions cost by 100 percent, then the overall reduction in service cost is about 10 percent. If, optimally, the equipment cost is reduced by 100 percent and the operations cost is reduced by 100 percent, then the overall cost of the Chapter 4 Figure 4-7 Next-generation SONET system-TDM trunk. Transport Bandwidth Channel Assignment SONET MUX Exiting Data Entering Packets Data Packets Traffic Tunneling (Packet Encapsulation) Ethernet Ports service is reduced by 15 percent. This last figure of merit, if reflected in the price of the broadband service quoted to the customer, is closer to the ball- park of where an end user might make the decision to switch providers. It should be noted that the Ethernet LECs (ELECs) are targeting midsize to large business users for TLS using VLAN-based campus-extended Gigabit Ethernet (GbE). However, most service providers need plans to offer the "triple play" of voice, data, and video on demand if they are to remain viable as businesses. Hence, it is important to have a technology that serves all of