Cause in LTE

RRC Connection Establishment Cause:
1. emergency
2. highPriorityAccess
3. mt-Access
4. mo-Signalling
5. mo-Data
6. delayTolerantAccess-v1020
7. spare2
8. spare1

RRC Connection Re-Establishment Cause:
1. reconfigurationFailure,
2. handoverFailure,
3. otherFailure,
4. spare1

RRC Connection Release Cause: 
        1. LoadBalancingTAURequired
2.  'other'
3. 'CS Fallback High Priority'
4. Normal

LTE Attach Type in Attach Request:
EPS attach type value (octet 1)
Bits
3 2 1
0 0 1 EPS attach
0 1 0 combined EPS/IMSI attach
1 1 0 EPS emergency attach
1 1 1 reserved
All other values are unused and shall be interpreted as "EPS attach", if received by the
network.
Bit 4 of octet 1 is spare and shall be coded as zero.

LTE Attach Result in Attach Accept:
EPS attach result value (octet 1)
Bits
3 2 1
0 0 1 EPS only
0 1 0 combined EPS/IMSI attach
All other values are reserved.
Bit 4 of octet 1 is spare and shall be coded as zero.

Additional update type value (AUTV) (octet 1)
       Bit
       1
       0 No additional information. If received it shall be interpreted as request for combined
attach or combined tracking area updating.
       1 SMS only
Bits 4 to 2 of octet 1 are spare and shall be all coded as zero.

Additional update result value (octet 1)
       Bits
       2 1
       0 0 no additional information
       0 1 CS Fallback not preferred
       1 0 SMS only
       1 1 reserved
Bits 4 and 3 of octet 1 are spare and shall all be coded as zero.


Tracking area update request Type:
EPS update type value (octet 1, bit 1 to 3)
Bits
3 2 1
0 0 0 TA updating
0 0 1 combined TA/LA updating
0 1 0 combined TA/LA updating with IMSI attach
0 1 1 periodic updating
1 0 0 unused; shall be interpreted as "TA updating", if received by the network.
1 0 1 unused; shall be interpreted as "TA updating", if received by the network.
All other values are reserved.
"Active" flag (octet 1, bit 4)
Bit
4
0 No bearer establishment requested
1 Bearer establishment requested

Tracking area update accept Result Type: 
EPS update result value (octet 1, bit 1 to 3)
Bits
3 2 1
0 0 0 TA updated
0 0 1 combined TA/LA updated
1 0 0 TA updated and ISR activated (NOTE)
1 0 1 combined TA/LA updated and ISR activated (NOTE)
All other values are reserved.
Bit 4 of octet 1 is spare and shall be coded as zero.

NOTE: Values "TA updated and ISR activated" and "combined TA/LA updated and
ISR activated" are used only for a UE supporting also A/Gb or Iu mode.


Type Of Detach: 
Type of detach (octet 1)
In the UE to network direction:
Bits
3 2 1
0 0 1 EPS detach
0 1 0 IMSI detach
0 1 1 combined EPS/IMSI detach
1 1 0 reserved
1 1 1 reserved
All other values are interpreted as "combined EPS/IMSI detach" in this version of the
protocol.
In the network to UE direction:
Bits
3 2 1
0 0 1 re-attach required
0 1 0 re-attach not required
0 1 1 IMSI detach
1 1 0 reserved
1 1 1 reserved
All other values are interpreted as "re-attach not required" in this version of the
protocol.
Switch off (octet 1)
In the UE to network direction:
Bit
4
0 normal detach
1 switch off
In the network to UE direction bit 4 is spare. The network shall set this bit to zero.



PDN type value (octet 1)
       Bits
       3 2 1
       0 0 1 IPv4
       0 1 0 IPv6
       0 1 1 IPv4v6
       1 0 0 unused; shall be interpreted as "IPv6" if received by the network
All other values are reserved.
Bit 4 of octet 1 is spare and shall be coded as zero.