ARSITEKTUR NGN

Transport stratum functions

The transport stratum functions include :

• transport functions and
• transport control functions

1. Transport functions

• Provide the connectivity for all components and physically separated functions within the NGN.
  • Provide support for the transfer of media information,
  • as well as the transfer of control and management information.
  • Transport functions include :
    • access network functions,
    • edge functions,
    • core transport functions, and
    • gateway functions.

2. Transport control functions

The Transport control functions include :

• Resource and Admission Control Functions and
• Network Attachment Control Functions.

Resource and Admission Control Functions (RACF), provide :

• QoS control (including resource reservation, admission control and gate control), NAPT and/or FW traversal control Functions over access and core transport networks.
• Admission control involves checking authorisation based on user profiles, SLAs, operator specific policy rules, service priority, and resource availability within access and core transport.

Network Attachment Control Functions (NACF)

• Provide registration at the access level and initialization of end-user functions for accessing NGN services.
• These functions provide network-level identification/ authentication, manage the IP address space of the access network, and authenticate access sessions.

3.Transport user profile function

• database user
  

• This abstract representation of the functional grouping in the service stratum includes the Service control functions and the Application/ Service support functions, as well as service user profiles

Service control functions

• The Service control functions include both session and non-session control, registration, and authentication and authorization functions at the service level. They can also include functions for controlling media resources, i.e., specialized resources and gateways at the service-signalling level.

Application/Service support functions

• The Application/Service support functions include functions such as the gateway, registration, authentication and authorization functions at the application level.

Service user profile functions

• • The service user profile functions represent the combination of user information and other control data into a single user profile function in the service stratum, in the form of a functional database. This functional database may be specified and implemented as a set of cooperating databases with functionalities residing in any part of the NGN.

3. End-user functions

No assumptions are made about the diverse end-user interfaces and end-user networks that may be connected to the NGN access network. Different categories of end-user equipment are supported in the NGN, from single-line legacy telephones to complex corporate networks. End-user equipment may be either mobile or fixed.