Small data communications
Technology for communicating small data between a user equipment (UE) and an evolved node B (eNB) is described. The UE may communicate with the eNB to establish a small data radio bearer (SDRB), wherein the SDRB is used for communicating the small data from the UE to the eNB. The UE may enter a power saving mode according to a power saving configuration. The UE or the eNB may maintain UE context information for the SDRB while the UE is in the power saving mode. The SDRB may be reestablished using the UE context information when the UE awakes from the power saving mode to enable the UE to communicate the small data on the SDRB to the eNB.
1. An evolved node B (eNB) operable to communicate small data with an user equipment (UE), the eNB having computer circuitry configured to:
communicate with the UE to establish a small data radio bearer (SDRB) for communicating the small data to the UE during an initial attachment procedure comprising:
receive a radio resource control (RRC) connection request message from the UE with an establishment cause of small data to enable the eNB to prepare a network setup for the SDRB;
send an RRC connection setup message from the eNB to the UE for an SDRB configuration to enable the UE to enter an RRC SDRB state;
communicate the small data from the eNB to the UE using core network (CN) bearers that are mapped to the SDRB while the UE is in the RRC SDRB state; and
transition from the RRC SDRB state to an RRC connected state.
2. The node of claim 1 , further configured to establish the SDRB for communicating the small data to the UE in a radio resource control (RRC) connection reconfiguration message communicated to the UE.
3. The node of claim 1 , further configured to communicate the small data to the UE using corresponding S1-U/related core network (CN) bearers that are mapped to the SDRB.
4. The node of claim 1 , wherein the UE context information is maintained at the node for a predefined period of time according to a timer.
5. The node of claim 1 , further configured to suspend the SDRB when the node is not communicating the small data to the UE.
6. The node of claim 1 , wherein the node is selected from a group consisting of a base station (BS), a Node B (NB), an evolved Node B (eNB), a baseband unit (BBU), a remote radio head (RRH), a remote radio equipment (RRE), or a remote radio unit (RRU).
7. The node of claim 1 , further configured to:
maintain UE context information for the SDRB, at the node, while the UE is in a power saving mode; and
receive the small data from the UE based on the UE context information for the SDRB when the UE wakes up from the power saving mode.
8. The node of claim 1 , wherein the computer circuitry is further configured to transition from the RRC SDRB state to an RRC idle state.
9. The node of claim 8 , wherein the computer circuitry is further configured to transition from the RRC SDRB state to an RRC idle state upon expiration of an inactivity timer.
10. The node of claim 8 , wherein the computer circuitry is further configured to transition from the RRC SDRB state to an RRC idle state based on signaling received from a network.
11. The node of claim 1 , wherein the computer circuitry is further configured to transition from the RRC SDRB state to an RRC idle state and then to an RRC connected state to enable control information and data to be communicated between the UE and the eNB.