As a result, employees require access to corporate network applications from wherever they are located. Security and QoS are two of many Layer 3 services that network managers need to deploy - intelligent networks that can support users and applications with scalable, reliable service. This is not only time consuming and expensive, but error-prone. Another problem is keeping track of who is doing what on the network. Network devices such as switches, routers, and firewalls enforce policies based on IP addresses and port numbers.
Businesses work with people who have names and job titles.
However, the fluid nature of employee access has created a need for dynamic IP address assignment upon user login. Many network managers find that DHCP simplifies the configuration of IP clients and dynamic addressing. Yet, while DHCP simplifies IP client configuration, mapping between a user and a statically assigned IP address no longer exists. Reconciling the mapping of changing IP addresses to users requires registration services. User registration services provide the link between network devices and the people who use the network, enabling the network to know who is doing what and provide proper QoS and security services to them.