[The LTE] In another angle observer terminal - access network - Core Network: AS / NAS to a

NAS

Non-Access Stratum, NAS

Architecture, location

Terminal - access network - different core network architecture, the concept of this model is the observation obtained from another perspective, as shown in FIG.

Here know NAS layer across the terminal and packet core network, and network access disjoint

Be responsible for

1. Session Management: includes session establishment, modification, release, and QoS negotiation.
2. User management: management including user data, and adhesion, detach. Note here that the Attach (attachment) are NAS concept
3. Security Management: includes authentication and encryption between the user and the network initialization.
4. Billing.

AS

Be responsible for

1. Radio bearer management: radio bearer assignment comprising, create, modify and release.
2. Processing the radio channel: a channel coding and modulation.
3. Encryption: refers only to its own encryption process, encryption and security algorithm selection initializing the responsibility of the NAS layer. Further, depending on the application end to end encryption may also be used, such as VPN.
4. Mobility Management: handover, cell selection and reselection like.