Along with the current states of idle and connected mode, 5G has added this new state. Let’s examine how this new state adds value to the 5G ecosystem and differs from the current state.
will gain some insight into the idle and connected, which will unavoidably reveal whether or not this new condition is closing the gap.
Idle state:
Neither AS context stored at gNB nor at the core network level as well. UE should start everything fresh.
Inactive state:
Here gNB has no context stored at AS level but it is in connect state at the backend i.e at the core network. ideally device will be just one step away to move to connect state and to start pump or receive data to and fro. this also improves the latency part unlike in idle state where device should make end to end connection.
Connect state:
Here UE will be end to end connected state from AS to Core network
Few Highlights – Summary between all states.
| RRC Idle – UE | RRC Inactive – UE | RRC Connected – UE |
| Monitors paging for 5G CN with 5G-S-TMSI | Monitors paging for 5G CN with 5G-S-TMSI and Ran paging with full I-RNTI | Monitors control channels associated with shared data channels to determine any data scheduled for it |
| Performs Neighbour cell measurements and cell selction(re-selection) | Performs Neighbour cell measurements and cell selction(re-selection) | Performs Neighbour cell measurements and cell selction(re-selection) |
| Acquires system information and can send SI request | Acquires system information and can send SI request | Acquires system information and can send SI request |
| Ue stores AS context | Ue stores AS context | |
| Perfroms RAN based notification updates either periodically or when device moves out configured RAN area. | Provides Channel quality and feedback information |
RRC release with Suspend config:
NR5G RRC OTA Packet — DL_DCCH / RRC Release Subscription ID = 1
message c1 : rrcRelease :
{
rrc-TransactionIdentifier 0,
criticalExtensions rrcRelease :
{
suspendConfig
{
fullI-RNTI ‘00000111 11110100 00000000 01100000 00111100’B,
shortI-RNTI ‘00000111 11110100 00111100’B,
ran-PagingCycle rf128,
ran-NotificationAreaInfo cellList :
{
{
plmn-Identity
{
mcc
{
404 or 405 },
mnc
{
network operator ID
}
},
ran-AreaCells
{
‘00000001 10000000 11110000 00000000 0010’B
}
}
},
t380 min5,
nextHopChainingCount 0
}
RRC Resume request:
NR5G RRC OTA Packet — UL_CCCH / RRC Resume Req Subscription ID = 1
value UL-CCCH-Message ::=
{
message c1 : rrcResumeRequest :
{
rrcResumeRequest
{
resumeIdentity ‘00000111 11110100 00111100’B,>>>>>>>>>>> UE will use same ID as shared in release with suspend config.
resumeMAC-I ‘00001101 01011001’B,
resumeCause mo-Data,>>> cause mo-data/mo-signalling,emergency etc…
spare ‘0’B
}
Ref: 38.331 and 38.304
