Most large-scale deployments of DSL by telecom carriers in North America and Europe use ATM to provide the end-to-end connections between the customer's premises and the service provider who provides access to the services used by the customer.
The use of ATM for the core of the access network, as shown in Figure 14.1, has several advantages for the access provider:
Telephone companies have widely deployed ATM networks to provide other data services to their customers. They are thus familiar with their architecture, engineering, and management. The connection-based nature of ATM provides an architecture that the telephone carriers are comfortable with and know how to operate.
The ATM-based core networks scale well ...