To respond to these customer demands and manage exponential growth within their networks, service providers must be able to do the following:

• provide more bandwidth at both the network edge and the core

• integrate with legacy operating support systems (OSSs) for optimized operations, administration, and maintenance (OAM)

• off-load analog data traffic from voice networks

• sell bandwidth in varying increments at a market-driven price

• engineer networks to allow for QoS and CoS for IP traffic

• create a network infrastructure that is shared among all customers and can still provide service guarantees and customer isolation

• make decisions on how to rationalize current voice and data network infrastructures

• scale the network in a manageable way

• quickly bring on new services

• manage customers not boxes

• make the right technology decisions for the future

• work with today's equipment

• roll out services in a profitable manner

• provide customers with customer-network-management features

As mentioned earlier, the two primary choices for upgrading the service provider's network are to expand the capacity of the router network by adding higher-capacity routers with fixed bandwidth backbone facilities or to add IP internetworking as a service on an existing or new ATM infrastructure. The service provider must examine each of these choices with a view to satisfying the above requirements within their existing and future network infrastructures. The following modules examine each of these technologies and their benefits.