8 Information elements coding

24.5873GPPProtocol aspectsRelease 16Stage 3TSVehicle-to-Everything (V2X) services in 5G System (5GS)

8.1 Overview

This clause contains the information elements coding for the messages used in the procedures described in the present document.

8.2 General

The sending entity shall set the value of a spare bit to zero. The receiving entity shall ignore the value of a spare bit.

The sending entity shall not set the value of a field to a reserved value. The receiving entity shall discard a message carrying a field with the value set to a reserved value.

8.3 Provisioning of parameters for V2X configuration signalling information elements

8.3.1 UPDS cause

The purpose of the UPDS cause information element is to indicate the reason why a UPDS request is rejected.

The UPDS cause information element is coded as shown in figure 8.3.2.1 and table 8.3.2.1.

The UPDS cause is a type 3 information element with 2 octets length.

8

7

6

5

4

3

2

1

UPDS cause IEI

octet 1

Cause value

octet 2

Figure 8.3.2.1: UPDS cause information element

Table 8.3.2.1: UPDS cause information element

Cause value (octet 2)

Bits

8

7

6

5

4

3

2

1

0

0

0

1

1

1

1

1

Request rejected, unspecified

0

0

1

0

0

0

0

0

Service option not supported

0

0

1

0

0

0

1

0

Service option temporarily out of order

0

0

1

0

0

0

1

1

PTI already in use

0

1

0

1

1

1

1

1

Semantically incorrect message

0

1

1

0

0

0

0

0

Invalid mandatory information

0

1

1

0

0

0

0

1

Message type non-existent or not implemented

0

1

1

0

0

0

1

0

Message type not compatible with the protocol state

0

1

1

0

0

0

1

1

Information element non-existent or not implemented

0

1

1

0

0

1

0

0

Conditional IE error

0

1

1

0

1

1

1

1

Protocol error, unspecified

Any other value received by the UE shall be treated as 0010 0010, "service option temporarily out of order". Any other value received by the network shall be treated as 0110 1111, "protocol error, unspecified".

8.3.2 Requested UE policies

The purpose of the Requested UE policies information element is to enable the UE to request the PCF to provide certain UE policies or certain UE policy subsets.

The Requested UE policies information element is coded as shown in figure 8.3.2.1 and table 8.3.2.1.

The Requested UE policies is a type 4 information element with a minimum length of 3 octets and a maximum length of 4 octets.

8

7

6

5

4

3

2

1

Requested UE policies IEI

octet 1

Length of Requested UE policies contents

octet 2

0

Spare

0

Spare

0

Spare

0

Spare

0

Spare

0

Spare

V2XUUI

V2XPC5I

octet 3

0

Spare

0

Spare

0

Spare

0

Spare

0

Spare

0

Spare

0

Spare

0

Spare

octet 4*

Figure 8.3.2.1: Requested UE policies information element

Table 8.3.2.1: Requested UE policies information element

UE policies for V2X communication over PC5 indicator (V2XPC5I) (octet 3, bit 1)

Bit

1

0

UE policies for V2X communication over PC5 not requested

1

UE policies for V2X communication over PC5 requested

UE policies for V2X communication over Uu indicator (V2XUUI) (octet 3, bit 2)

Bit

2

0

UE policies for V2X communication over Uu not requested

1

UE policies for V2X communication over Uu requested

Bit 3 to 8 of octet 3 and bits of octet 4 are spare and shall be coded as zero.

8.4 V2X communication over PC5 signalling information elements

8.4.1 PC5 signalling message type

The purpose of the PC5 signalling message type information element is to indicate the type of messages used in PC5 signalling protocol.

The value part of the PC5 signalling message type information element used in the PC5 signalling messages is coded as shown in table 8.4.1.1.

The PC5 signalling message type is a type 3 information element, with the length of 1 octet.

Table 8.4.1.1: PC5 signalling message type

Bits

8

7

6

5

4

3

2

1

0

0

0

0

0

0

0

1

DIRECT LINK ESTABLISHMENT REQUEST

0

0

0

0

0

0

1

0

DIRECT LINK ESTABLISHMENT ACCEPT

0

0

0

0

0

0

1

1

DIRECT LINK ESTABLISHMENT REJECT

0

0

0

0

0

1

0

0

DIRECT LINK MODIFICATION REQUEST

0

0

0

0

0

1

0

1

DIRECT LINK MODIFICATION ACCEPT

0

0

0

0

0

1

1

0

DIRECT LINK MODIFICATION REJECT

0

0

0

0

0

1

1

1

DIRECT LINK RELEASE REQUEST

0

0

0

0

1

0

0

0

DIRECT LINK RELEASE ACCEPT

0

0

0

0

1

0

0

1

DIRECT LINK KEEPALIVE REQUEST

0

0

0

0

1

0

1

0

DIRECT LINK KEEPALIVE RESPONSE

0

0

0

0

1

0

1

1

DIRECT LINK AUTHENTICATION REQUEST

0

0

0

0

1

1

0

0

DIRECT LINK AUTHENTICATION RESPONSE

0

0

0

0

1

1

0

1

DIRECT LINK AUTHENTICATION REJECT

0

0

0

0

1

1

1

0

DIRECT LINK SECURITY MODE COMMAND

0

0

0

0

1

1

1

1

DIRECT LINK SECURITY MODE COMPLETE

0

0

0

1

0

0

0

0

DIRECT LINK SECURITY MODE REJECT

0

0

0

1

0

0

0

1

DIRECT LINK REKEYING REQUEST

0

0

0

1

0

0

1

0

DIRECT LINK REKEYING RESPONSE

0

0

0

1

0

0

1

1

DIRECT LINK IDENTIFIER UPDATE REQUEST

0

0

0

1

0

1

0

0

DIRECT LINK IDENTIFIER UPDATE ACCEPT

0

0

0

1

0

1

0

1

DIRECT LINK IDENTIFIER UPDATE ACK

0

0

0

1

0

1

1

0

DIRECT LINK IDENTIFIER UPDATE REJECT

0

0

0

1

0

1

1

1

DIRECT LINK AUTHENTICATION FAILURE

8.4.2 Sequence number

The purpose of the Sequence number information element is to uniquely identify a PC5 signalling message being sent or received. The sending UE will increment the sequence number for each outgoing new PC5 signalling message.

The Sequence number information element is an integer in the 0-255 range.

The Sequence number is a type 3 information element, with a length of 1 octet.

8.4.3 V2X service identifier

The purpose of the V2X service identifier parameter is to carry the identifier of a V2X service.

The V2X service identifier information element is coded as shown in figure 8.4.3.1 and table 8.4.3.1.

The V2X service identifier is a type 4 information element with a minimum length of 6 octets.

8

7

6

5

4

3

2

1

V2X service identifier IEI

octet 1

Length of V2X service identifier contents

octet 2

V2X service identifier 1

octet 3

octet 6

V2X service identifier 2

octet 7*

octet 10*

octet 11*

octet 4n-2*

V2X service identifier n

octet 4n-1*

octet 4n+2*

Figure 8.4.3.1: V2X service identifier information element

Table 8.4.3.1: V2X service identifier information element

V2X service identifier:

The V2X service identifier field contains a binary coded V2X service identifier as specified in ISO TS 17419 ITS-AID AssignedNumbers [18].

8.4.4 Application layer ID

The purpose of the Application layer ID parameter information element carries an application layer ID as specified in 3GPP TS 23.287 [3].

The Application layer ID information element is coded as shown in figure 8.4.4.1 and table 8.4.4.1.

The Application layer ID is a type 4 information element.

8

7

6

5

4

3

2

1

Application layer ID IEI

octet 1

Length of Application layer ID contents

octet 2

Application layer ID contents

octet 3

octet m

Figure 8.4.4.1: Application layer ID information element

Table 8.4.4.1: Application layer ID information element

The length of Application layer ID contents field contains the binary coded representation of the length of the Application layer ID contents field.

The Application layer ID contents field contains the octets indicating the Application layer ID. The format of the Application layer ID parameter is out of scope of this specification.

8.4.5 PC5 QoS flow descriptions

The purpose of the PC5 QoS flow descriptions information element is to indicate a set of PC5 QoS flow descriptions to be used by the UE over the direct link, where each PC5 QoS flow description is a set of parameters as described in clause 5.4.2 of 3GPP TS 23.287 [3].

The PC5 QoS flow descriptions is a type 6 information element with a minimum length of 6 octets. The maximum length for the information element is 65538 octets.

The PC5 QoS flow descriptions information element is coded as shown in figure 8.4.5.1, figure 8.4.5.2, figure 8.4.5.3, figure 8.4.5.4, and table 8.4.5.1.

8

7

6

5

4

3

2

1

PC5 QoS flow descriptions IEI

octet 1

Length of PC5 QoS flow descriptions contents

octet 2

octet 3

PC5 QoS flow description 1

octet 4

octet u

PC5 QoS flow description 2

octet u+1

octet v

octet v+1

octet w

PC5 QoS flow description n

octet w+1

octet x

Figure 8.4.5.1: PC5 QoS flow descriptions information element

8

7

6

5

4

3

2

1

0

Spare

0

Spare

PQFI

octet 4

Operation code

0

Spare

0

Spare

0

Spare

0

Spare

0

Spare

octet 5

0

Spare

E

Number of parameters

octet 6

Associated V2X service identifiers

octet 7*

octet k*

Parameters list

octet k+1*

octet u*

Figure 8.4.5.2: PC5 QoS flow description

8

7

6

5

4

3

2

1

Parameter 1

octet k+1

octet m

Parameter 2

octet m+1

octet n

octet n+1

octet o

Parameter n

octet o+1

octet u

Figure 8.4.5.3: Parameters list

8

7

6

5

4

3

2

1

Parameter identifier

octet k+1

Length of parameter contents

octet k+2

Parameter contents

octet k+3

octet m

Figure 8.4.5.4: Parameter

Table 8.4.4.1: PC5 QoS flow descriptions information element

PC5 QoS flow identifier (PQFI) (bits 6 to 1 of octet 4)

PQFI field contains the PC5 QoS flow identifier.

Bits

6 5 4 3 2 1

0 0 0 0 0 1 PQFI 1

to

1 1 1 1 1 1 PQFI 63

The UE shall not set the PQFI value to 0.

Operation code (bits 8 to 6 of octet 5)

Bits

8 7 6

0 0 1 Create new PC5 QoS flow description

0 1 0 Delete existing PC5 QoS flow description

0 1 1 Modify existing PC5 QoS flow description

All other values are reserved.

E bit (bit 7 of octet 6)

For the "create new PC5 QoS flow description" operation, the E bit is encoded as follows:

Bit
7

0 reserved

1 parameters list is included

For the "Delete existing PC5 QoS flow description" operation, the E bit is encoded as follows:

Bit
7

0 parameters list is not included

1 reserved

For the "modify existing PC5 QoS flow description" operation, the E bit is encoded as follows:

Bit
7

0 extension of previously provided parameters

1 replacement of all previously provided parameters

If the E bit is set to "parameters list is not included", the number of parameters field has zero value. If the E bit is set to "parameters list is included", the number of parameters field has non-zero value. If the E bit is set to "extension of previously provided parameters" or "replacement of all previously provided parameters", the number of parameters field has non-zero value. If the E bit is set to "extension of previously provided parameters" and one of the parameters in the new parameters list already exists in the previously provided parameters, the parameter shall be set to the new value.

Number of parameters (bits 6 to 1 of octet 6)

The number of parameters field contains the binary coding for the number of parameters in the parameters list field. The number of parameters field is encoded in bits 6 through 1 of octet 6 where bit 6 is the most significant and bit 1 is the least significant bit.

Associated V2X service identifiers (octet 7 to k)

The associated V2X service identifiers field contains a variable number of V2X service identifiers associated with the PC5 QoS flow. Associated V2X service identifiers field is coded as the length and value part of V2X service identifier information element as specified in clause 8.4.3 starting with the second octet.

Parameters list (octets k+1 to u)

The parameters list contains a variable number of parameters.

Each parameter included in the parameters list is of variable length and consists of:

– a parameter identifier (1 octet);
– the length of the parameter contents (1 octet); and
– the parameter contents itself (variable amount of octets).

The parameter identifier field is used to identify each parameter included in the parameters list and it contains the hexadecimal coding of the parameter identifier. Bit 8 of the parameter identifier field contains the most significant bit and bit 1 contains the least significant bit. In this version of the protocol, the following parameter identifiers are specified:

– 01H (PQI);
– 02H (GFBR); (see NOTE)

– 03H (MFBR); (see NOTE)

– 04H (Averaging window) ;

– 05H (Resource type);

– 06H (Default priority level);

– 07H (Packet delay budget);

– 08H (Packet error rate);

– 09H (Default maximum data burst volume).

If the parameters list contains a parameter identifier that is not supported by the receiving entity the corresponding parameter shall be discarded.

The length of parameter contents field contains the binary coded representation of the length of the parameter contents field. The first bit in transmission order is the most significant bit.

When the parameter identifier indicates PQI, the parameter contents field contains the binary representation of PQI that is one octet in length.

PQI:

Bits

8 7 6 5 4 3 2 1

0 0 0 0 0 0 0 0 Reserved

0 0 0 0 0 0 0 1

to Spare

0 0 0 1 0 1 0 0

0 0 0 1 0 1 0 1 PQI 21

0 0 0 1 0 1 1 0 PQI 22

0 0 0 1 0 1 1 1 PQI 23

0 0 0 1 1 0 0 0

to Spare

0 0 1 1 0 1 1 0

0 0 1 1 0 1 1 1 PQI 55

0 0 1 1 1 0 0 0 PQI 56

0 0 1 1 1 0 0 1 PQI 57

0 0 1 1 1 0 1 0 PQI 58

0 0 1 1 1 0 1 1 PQI 59

0 0 1 1 1 1 0 0

to Spare

0 1 0 1 1 0 0 1

0 1 0 1 1 0 1 0 PQI 90

0 1 0 1 1 0 1 1 PQI 91

0 1 0 1 1 1 0 0

to Spare

0 1 1 1 1 1 1 1

1 0 0 0 0 0 0 0

to Operator-specific PQIs

1 1 1 1 1 1 1 0

1 1 1 1 1 1 1 1 Reserved

The UE shall consider all other values not explicitly defined in this version of the protocol as unsupported.

When the parameter identifier indicates "GFBR", the parameter contents field contains one octet indicating the unit of the guaranteed flow bit rate followed by two octets containing the value of the guaranteed flow bit rate.

Unit of the guaranteed flow bit rate (octet 1)

Bits

8 7 6 5 4 3 2 1

0 0 0 0 0 0 0 0 value is not used

0 0 0 0 0 0 0 1 value is incremented in multiples of 1 Kbps

0 0 0 0 0 0 1 0 value is incremented in multiples of 4 Kbps

0 0 0 0 0 0 1 1 value is incremented in multiples of 16 Kbps

0 0 0 0 0 1 0 0 value is incremented in multiples of 64 Kbps

0 0 0 0 0 1 0 1 value is incremented in multiples of 256 Kbps

0 0 0 0 0 1 1 0 value is incremented in multiples of 1 Mbps

0 0 0 0 0 1 1 1 value is incremented in multiples of 4 Mbps

0 0 0 0 1 0 0 0 value is incremented in multiples of 16 Mbps

0 0 0 0 1 0 0 1 value is incremented in multiples of 64 Mbps

0 0 0 0 1 0 1 0 value is incremented in multiples of 256 Mbps

0 0 0 0 1 0 1 1 value is incremented in multiples of 1 Gbps

0 0 0 0 1 1 0 0 value is incremented in multiples of 4 Gbps

0 0 0 0 1 1 0 1 value is incremented in multiples of 16 Gbps

0 0 0 0 1 1 1 0 value is incremented in multiples of 64 Gbps

0 0 0 0 1 1 1 1 value is incremented in multiples of 256 Gbps

0 0 0 1 0 0 0 0 value is incremented in multiples of 1 Tbps

0 0 0 1 0 0 0 1 value is incremented in multiples of 4 Tbps

0 0 0 1 0 0 1 0 value is incremented in multiples of 16 Tbps

0 0 0 1 0 0 1 1 value is incremented in multiples of 64 Tbps

0 0 0 1 0 1 0 0 value is incremented in multiples of 256 Tbps

0 0 0 1 0 1 0 1 value is incremented in multiples of 1 Pbps

0 0 0 1 0 1 1 0 value is incremented in multiples of 4 Pbps

0 0 0 1 0 1 1 1 value is incremented in multiples of 16 Pbps

0 0 0 1 1 0 0 0 value is incremented in multiples of 64 Pbps

0 0 0 1 1 0 0 1 value is incremented in multiples of 256 Pbps

Other values shall be interpreted as multiples of 256 Pbps in this version of the protocol.

Value of the guaranteed flow bit rate (octets 2 and 3)

Octets 2 and 3 represent the binary coded value of the guaranteed flow bit rate in units defined by the unit of the guaranteed flow bit rate.

When the parameter identifier indicates "GFBR downlink", the parameter contents field contains one octet indicating the unit of the guaranteed flow bit rate for downlink followed by two octets containing the value of the guaranteed flow bit rate for downlink.

When the parameter identifier indicates "MFBR ", the parameter contents field contains the one octet indicating the unit of the maximum flow bit rate followed by two octets containing the value of maximum flow bit rate.

Unit of the maximum flow bit rate (octet 1)

The coding is identical to that of the unit of the guaranteed flow bit rate.

Value of the maximum flow bit rate (octets 2 and 3)

Octets 2 and 3 represent the binary coded value of the maximum flow bit rate in units defined by the unit of the maximum flow bit rate.

When the parameter identifier indicates "averaging window", the parameter contents field contains the binary representation of the averaging window for both uplink and downlink in milliseconds and the parameter contents field is two octets in length.

When the parameter identifier indicates "resource type", the parameter contents field contains the binary representation of the resource type that is one octet in length.

Resource type:

Bits

8 7 6 5 4 3 2 1

0 0 0 0 0 0 0 0 Reserved

0 0 0 0 0 0 0 1 Non-GBR

0 0 0 0 0 0 1 0 GBR

0 0 0 0 0 0 1 1 Delay critical GBR

0 0 0 0 0 1 0 0

to Spare

1 1 1 1 1 1 1 1

When the parameter identifier indicates "default priority level", the parameter contents field contains the binary representation of the default priority level that is one octet in length.

Default priority level:

Bits

8 7 6 5 4 3 2 1

0 0 0 0 0 0 0 0 Reserved

0 0 0 0 0 0 0 1 1

0 0 0 0 0 0 1 0 2

0 0 0 0 0 0 1 1 3

0 0 0 0 0 1 0 0 4

0 0 0 0 0 1 0 1 5

0 0 0 0 0 1 1 0 6

0 0 0 0 0 1 1 1 7

0 0 0 0 1 0 0 0 8

0 0 0 0 1 0 0 1

to Spare

1 1 1 1 1 1 1 1

When the parameter identifier indicates "packet delay budget", the parameter contents field contains the binary representation of the packet delay budget for both uplink and downlink in milliseconds and the parameter contents field is two octets in length.

When the parameter identifier indicates "packet error rate", the parameter contents field contains the binary representation of the power of 10-1 for both uplink and downlink and the parameter contents field is one octet in length.

When the parameter identifier indicates "default maximum data burst volume", the parameter contents field contains the binary representation of the default maximum data burst volume for both uplink and downlink in bytes and the parameter contents field is two octets in length.

NOTE: The GFBR and MFBR apply to both directions of the PC5 unicast link.

8.4.6 IP address configuration

The purpose of the IP address configuration information element is to indicate the configuration options for IP address used by the UE over this direct link.

The IP address configuration is a type 3 information element with the length of 2 octets.

The IP address configuration information element is coded as shown in figure z.3.1.6.1 and table z.3.1.6.1.

8

7

6

5

4

3

2

1

IP address configuration IEI

octet 1

IP address configuration content

octet 2

Figure 8.4.6.1: IP address configuration information element

Table 8.4.6.1: IP address configuration information element

IP address configuration value (octet 2)

Bits

4

3

2

1

0

0

0

1

IPv6 Router

0

0

1

0

address allocation not supported

All other values are reserved.

Bit 5 to 8 of octet 2 are spare and shall be coded as zero.

8.4.7 Link local IPv6 address

The purpose of the Link local IPv6 address information element is to indicate the link local IPv6 address.

The Link local IPv6 address is a type 3 information element with the length of 17 octets.

The Link local IPv6 address information element is coded as shown in figure 8.4.7.1 and table 8.4.7.1.

8

7

6

5

4

3

2

1

Link local IPv6 address IEI

octet 1

Link local IPv6 address content

octet 2

octet 17

Figure 8.4.7.1: Link local IPv6 address information element

Table 8.4.7.1: Link local IPv6 address information element

Link local IPv6 address value (octet 2 to 17)

This contains the 128-bit IPv6 address. This IPv6 address is encoded as a 128-bit address according to IETF RFC 4291 [15].

8.4.8 Link modification operation code

The purpose of the Link modification operation code information element is to indicate what the operation of the PC5 unicast link modification procedure triggered by initiating UE is.

The Link modification operation code is a type 3 information element, with a length of 2 octets.

The Link modification operation code information element is coded as shown in figure 8.4.8.1 and table 8.4.8.1.

8

7

6

5

4

3

2

1

Link modification operation code IEI

octet 1

Link modification operation code

octet 2

Figure 8.4.8.1: Link modification operation code information element

Table 8.4.8.1: Link modification operation code information element

Link modification operation code (octet 2)

Bits

4

3

2

1

0

0

0

1

void

0

0

1

0

void

0

0

1

1

Add new PC5 QoS flow(s) to the existing PC5 unicast link

0

1

0

0

Modify PC5 QoS parameters of the existing PC5 QoS flow(s)

0

1

0

1

Remove existing PC5 QoS flow(s) from the existing PC5 unicast link

0

1

1

0

Associate new V2X service(s) with existing PC5 QoS flow(s)

0

1

1

1

Remove V2X service(s) from existing PC5 QoS flow(s)

1

0

0

0

to

Spare

1

1

1

0

1

1

1

1

Reserved

Bit 5 to 8 of octet 2 are spare and shall be coded as zero.

8.4.9 PC5 signalling protocol cause

The purpose of the PC5 signalling protocol cause information element is to indicate the cause used in the PC5 signalling protocol procedures.

The PC5 signalling protocol cause is a type 3 information element with a length of 2 octets.

The PC5 signalling protocol cause information element is coded as shown in figure 8.4.9.1 and table 8.4.9.1.

8

7

6

5

4

3

2

1

PC5 signalling protocol cause IEI

octet 1

PC5 signalling cause value

octet 2

Figure 8.4.9.1: PC5 signalling protocol cause information element

Table 8.4.9.1: PC5 signalling protocol cause information element

PC5 signalling cause value (octet 2)

Bits

8

7

6

5

4

3

2

1

0

0

0

0

0

0

0

1

Direct communication to the target UE not allowed

0

0

0

0

0

0

1

0

Direct communication to the target UE no longer needed

0

0

0

0

0

0

1

1

Conflict of layer-2 ID for unicast communication is detected

0

0

0

0

0

1

0

0

Direct connection is not available anymore

0

0

0

0

0

1

0

1

Lack of resources for PC5 unicast link

0

0

0

0

0

1

1

0

Authentication failure

0

0

0

0

0

1

1

1

Integrity failure

0

0

0

0

1

0

0

0

UE security capabilities mismatch

0

0

0

0

1

0

0

1

LBSs of KNRP-sess ID conflict

0

0

0

0

1

0

1

0

UE PC5 unicast signalling security policy mismatch

0

0

0

0

1

0

1

1

Required service not allowed

0

0

0

0

1

1

0

0

Security policy not aligned

0

1

1

0

1

1

1

1

Protocol error, unspecified

Any other value received by the UE shall be treated as 0110 1111, "protocol error, unspecified".

8.4.10 Keep-alive counter

The purpose of the Keep-alive counter information element is to indicate the keep-alive counter which is a 32-bit counter used for the PC5 unicast link keep-alive procedure.

The Keep-alive counter is a type 3 information element with a length of 5 octets.

The Keep-alive counter information element is coded as shown in figure 8.4.10.1 and table 8.4.10.1.

8

7

6

5

4

3

2

1

Keep-alive counter IEI

octet 1

Keep-alive counter contents

octet 2

octet 5

Figure 8.4.10.1: Keep-alive counter information element

Table 8.4.10.1: Keep-alive counter information element

Keep-alive counter contents (octet 2 to 5)

This field contains the 32-bit keep-alive counter.

8.4.11 Maximum inactivity period

The purpose of the Maximum inactivity period information element is to indicate the maximum inactivity period of the initiating UE during a PC5 unicast link keep-alive procedure.

The Maximum inactivity period is a type 3 information element, with a length of 5 octets.

The Maximum inactivity period information element is coded as shown in figure 8.4.11.1 and table 8.4.11.1.

8

7

6

5

4

3

2

1

Maximum inactivity period IEI

octet 1

Maximum inactivity period contents

octet 2

octet 5

Figure 8.4.11.1: Maximum inactivity period information element

Table 8.4.11.1: Maximum inactivity period information element

Maximum inactivity period contents (octet 2 to 5)

This field contains the binary encoding of the maximum inactivity period expressed in units of seconds.

8.4.12 Key establishment information container

The Key establishment information container information element contains information for PC5 unicast link key establishment.

The Key establishment information container is a type 6 information element with a minimum length of 4 octets.

The Key establishment information container information element is coded as shown in figure 8.4.12.1 and table 8.4.12.1.

8

7

6

5

4

3

2

1

Key establishment information container IEI

octet 1

Length of key establishment information container contents

octet 2

octet 3

Key establishment information container contents

octet 4

octet n

Figure 8.4.a.1: Key establishment information container information element

Table 8.4.a.1: Key establishment information container information element

Key establishment information container contents (octet 4 to n)

This field contains the key establishment information container.

8.4.13 Nonce

The Nonce information element contains a 128-bit nonce used during PC5 unicast link security establishment.

The Nonce information element is a type 3 information element, with a length of 17 octets.

The Nonce information element is coded as shown in figure 8.4.13.1 and table 8.4.13.1.

8

7

6

5

4

3

2

1

Nonce IEI

octet 1

Nonce contents

octet 2

octet 17

Figure 8.4.13.1: Nonce information element

Table 8.4.13.1: Nonce information element

Nonce contents (octet 2 to 17)

This field contains the 128-bit nonce value.

8.4.14 UE security capabilities

The UE security capabilities information element is used to indicate which security algorithms are supported by the UE.

The UE security capabilities is a type 4 information element with a minimum length of 4 octets and a maximum length of 10 octets.

The UE security capabilities information element is coded as shown in figure 8.4.14.1 and table 8.4.14.1.

8

7

6

5

4

3

2

1

UE security capabilities IEI

octet 1

Length of UE security capabilities contents

octet 2

5G-EA0

128-

5G-EA1

128-

5G-EA2

128-

5G-EA3

5G-EA4

5G-EA5

5G-EA6

5G-EA7

octet 3

5G-IA0

128-

5G-IA1

128-

5G-IA2

128-

5G-IA3

5G-IA4

5G-IA5

5G-IA6

5G-IA7

octet 4

0

0

0

0

0

0

0

0

Spare

octet 5* -10*

Figure 8.4.14.1: UE security capabilities information element

Table 8.4.14.1: UE security capabilities information element

5GS encryption algorithms supported (octet 3)

5GS encryption algorithm 5G-EA0 supported (octet 3, bit 8)

0

5GS encryption algorithm 5G-EA0 not supported

1

5GS encryption algorithm 5G-EA0 supported

5GS encryption algorithm 128-5G-EA1 supported (octet 3, bit 7)

0

5GS encryption algorithm 128-5G-EA1 not supported

1

5GS encryption algorithm 128-5G-EA1 supported

5GS encryption algorithm 128-5G-EA2 supported (octet 3, bit 6)

0

5GS encryption algorithm 128-5G-EA2 not supported

1

5GS encryption algorithm 128-5G-EA2 supported

5GS encryption algorithm 128-5G-EA3 supported (octet 3, bit 5)

0

5GS encryption algorithm 128-5G-EA3 not supported

1

5GS encryption algorithm 128-5G-EA3 supported

5GS encryption algorithm 5G-EA4 supported (octet 3, bit 4)

0

5GS encryption algorithm 5G-EA4 not supported

1

5GS encryption algorithm 5G-EA4 supported

5GS encryption algorithm 5G-EA5 supported (octet 3, bit 3)

0

5GS encryption algorithm 5G-EA5 not supported

1

5GS encryption algorithm 5G-EA5 supported

5GS encryption algorithm 5G-EA6 supported (octet 3, bit 2)

0

5GS encryption algorithm 5G-EA6 not supported

1

5GS encryption algorithm 5G-EA6 supported

5GS encryption algorithm 5G-EA7 supported (octet 3, bit 1)

0

5GS encryption algorithm 5G-EA7 not supported

1

5GS encryption algorithm 5G-EA7 supported

5GS integrity algorithms supported (octet 4)

5GS integrity algorithm 5G-IA0 supported (octet 4, bit 8)

0

5GS integrity algorithm 5G-IA0 not supported

1

5GS integrity algorithm 5G-IA0 supported

5GS integrity algorithm 128-5G-IA1 supported (octet 4, bit 7)

0

5GS integrity algorithm 128-5G-IA1 not supported

1

5GS integrity algorithm 128-5G-IA1 supported

5GS integrity algorithm 128-5G-IA2 supported (octet 4, bit 6)

0

5GS integrity algorithm 128-5G-IA2 not supported

1

5GS integrity algorithm 128-5G-IA2 supported

5GS integrity algorithm 128-5G-IA3 supported (octet 4, bit 5)

0

5GS integrity algorithm 128-5G-IA3 not supported

1

5GS integrity algorithm 128-5G-IA3 supported

5GS integrity algorithm 5G-IA4 supported (octet 4, bit 4)

0

5GS integrity algorithm 5G-IA4 not supported

1

5GS integrity algorithm 5G-IA4 supported

5GS integrity algorithm 5G-IA5 supported (octet 4, bit 3)

0

5GS integrity algorithm 5G-IA5 not supported

1

5GS integrity algorithm 5G-IA5 supported

5GS integrity algorithm 5G-IA6supported (octet 4, bit 2)

0

5GS integrity algorithm 5G-IA6 not supported

1

5GS integrity algorithm 5G-IA6 supported

5GS integrity algorithm 5G-IA7 supported (octet 4, bit 1)

0

5GS integrity algorithm 5G-IA7 not supported

1

5GS integrity algorithm 5G-IA7 supported

8.4.15 UE PC5 unicast signalling security policy

The purpose of the UE PC5 unicast signalling security policy information element is to indicate the UE’s configuration for integrity protection and ciphering of PC5 signalling messages.

The UE PC5 unicast signalling security policy is a type 3 information element with a length of 2 octets.

The UE PC5 unicast signalling security policy information element is coded as shown in figure 8.4.15.1.1 and table 8.4.15.1.

8

7

6

5

4

3

2

1

UE PC5 unicast signalling security policy IEI

octet 1

0

spare

Signalling ciphering policy

0

spare

Signalling integrity protection policy

octet 2

Figure 8.4.15.1: UE PC5 unicast signalling security policy information element

Table 8.4.15.1: UE PC5 unicast signalling security policy information element

Signalling integrity protection policy (octet 2, bit 1 to 3)

Bits

3

2

1

0

0

0

Signalling integrity protection not needed

0

0

1

Signalling integrity protection preferred

0

1

0

Signalling integrity protection required

0

1

1

to Spare

1

1

0

1

1

1

Reserved

If the UE receives a signalling integrity protection policy value that the UE does not understand, the UE shall interpret the value as 010 "Signalling integrity protection required".

Signaling ciphering policy (octet 2, bit 5 to 7)

Bits

7

6

5

0

0

0

Signalling ciphering not needed

0

0

1

Signalling ciphering preferred

0

1

0

Signalling ciphering required

0

1

1

to Spare

1

1

0

1

1

1

Reserved

If the UE receives a signalling ciphering policy value that the UE does not understand, the UE shall interpret the value as 010 "Signalling ciphering required".

Bit 4 and 8 of octet 2 are spare and shall be coded as zero.

8.4.16 MSBs of KNRP-sess ID

The purpose of the MSBs of KNRP-sess ID information element is to carry the 8 most significant bits of the KNRP-sess ID.

The MSBs of KNRP-sess ID information element is a type 3 information element with a length of 2 octets.

The MSBs of KNRP-sess ID information element is coded as shown in figure 8.4.16.1 and table 8.4.16.1.

8

7

6

5

4

3

2

1

MSBs of KNRP-sess ID IEI

octet 1

MSBs of KNRP-sess ID contents

octet 2

Figure 8.4.16.1: MSBs of KNRP-sess ID information element

Table 8.4.16.1: MSBs of KNRP-sess ID information element

MSBs of KNRP-sess ID contents (octet 2)

This field contains the 8 most significant bits of KNRP-sess ID.

NOTE: This field is set to all zeros if the KNRP-sess ID is not generated, i.e., the null integrity algorithm is used.

8.4.17 KNRP ID

The purpose of the KNRP ID information element is to carry the identity of the KNRP held by a UE.

The KNRP ID is a type 3 information element with a length of 5 octets.

The KNRP ID information element is coded as shown in figure 8.4.17.1 and table 8.4.17.1

8

7

6

5

4

3

2

1

KNRP ID IEI

octet 1

KNRP ID contents

octet 2

octet 5

Figure 8.4.17.1: KNRP ID information element

Table 8.4.17.1: KNRP ID information element

KNRP ID contents (octet 2 to 5)

This field contains the 32-bit identifier of a KNRP.

8.4.18 Selected security algorithms

The purpose of the Selected security algorithms information element is to indicate the algorithms to be used for ciphering and integrity protection.

The Selected security algorithms is a type 3 information element with a length of 2 octets.

The Selected security algorithms information element is coded as shown in figure 8.4.18.1.1 and table 8.4.18.1.

8

7

6

5

4

3

2

1

Selected security algorithms IEI

octet 1

0

spare

Type of ciphering algorithm

0

spare

Type of integrity protection algorithm

octet 2

Figure 8.4.18.1: Selected security algorithms information element

Table 8.4.18.1: Selected security algorithms information element

Type of integrity protection algorithm (octet 2, bit 1 to 3)

Bits

3

2

1

0

0

0

5GS integrity algorithm 5G-IA0 (null integrity protection algorithm)

0

0

1

5GS integrity algorithm 128-5G-IA1

0

1

0

5GS integrity algorithm 128-5G-IA2

0

1

1

5GS integrity algorithm 128-5G-IA3

1

0

0

5GS integrity algorithm 5G-IA4

1

0

1

5GS integrity algorithm 5G-IA5

1

1

0

5GS integrity algorithm 5G-IA6

1

1

1

5GS integrity algorithm 5G-IA7

Type of ciphering algorithm (octet 2, bit 5 to 7)

Bits

7

6

5

0

0

0

5GS encryption algorithm 5G-EA0 (null ciphering algorithm)

0

0

1

5GS encryption algorithm 128-5G-EA1

0

1

0

5GS encryption algorithm 128-5G-EA2

0

1

1

5GS encryption algorithm 128-5G-EA3

1

0

0

5GS encryption algorithm 5G-EA4

1

0

1

5GS encryption algorithm 5G-EA5

1

1

0

5GS encryption algorithm 5G-EA6

1

1

1

5GS encryption algorithm 5G-EA7

Bit 4 and 8 of octet 2 are spare and shall be coded as zero.

8.4.19 LSBs of KNRP-sess ID

The purpose of the LSBs of KNRP-sess ID information element is to carry the 8 least significant bits of the KNRP-sess ID.

The LSBs of KNRP-sess ID is a type 3 information element with a length of 2 octets.

The LSBs of KNRP-sess ID information element is coded as shown in figure 8.4.19.1 and table 8.4.19.1.

8

7

6

5

4

3

2

1

LSBs of KNRP-sess ID

octet 1

LSBs of KNRP-sess ID contents

octet 2

Figure 8.4.19.1: LSBs of KNRP-sess ID information element

Table 8.4.19.1: LSBs of KNRP-sess ID information element

LSBs of KNRP-sess ID contents (octet 2)

This field contains the 8 least significant bits of KNRP-sess ID.

8.4.20 MSBs of KNRP ID

The purpose of the MSBs of KNRP ID information element is to carry the 16 most significant bits of the KNRP ID.

The MSBs of KNRP ID is a type 3 information element with a length of 3 octets.

The MSBs of KNRP ID information element is coded as shown in figure 8.4.20.1 and table 8.4.20.1.

8

7

6

5

4

3

2

1

MSBs of KNRP ID IEI

octet 1

MSBs of KNRP ID contents

octet 2

octet 3

Figure 8.4.20.1: MSBs of KNRP ID information element

Table 8.4.20.1: MSBs of KNRP ID information element

MSBs of KNRP ID contents (octet 2 to 3)

This field contains the 16 most significant bits of KNRP ID.

8.4.21 LSBs of KNRP ID

The purpose of the LSBs of KNRP ID information element is to carry the 16 least significant bits of the KNRP ID.

The LSBs of KNRP ID is a type 3 information element with a length of 3 octets.

The LSBs of KNRP ID information element is coded as shown in figure 8.4.21.1 and table 8.4.21.1.

8

7

6

5

4

3

2

1

LSBs of KNRP ID IEI

octet 1

LSBs of KNRP ID contents

octet 2

octet 3

Figure 8.4.21.1: LSBs of KNRP ID information element

Table 8.4.21.1: LSBs of KNRP ID information element

LSBs of KNRP ID contents (octet 2 to 3)

This field contains the 16 least significant bits of KNRP ID.

8.4.22 UE PC5 unicast user plane security policy

The purpose of the UE PC5 unicast user plane security policy information element is to indicate the UE’s configuration for integrity protection and ciphering of PC5 user plane data.

The UE PC5 unicast user plane security policy is a type 3 information element with a length of 2 octets.

The UE PC5 unicast user plane security policy information element is coded as shown in figure 8.4.22.1.1 and table 8.4.22.1.

8

7

6

5

4

3

2

1

UE PC5 unicast user plane security policy IEI

octet 1

0

spare

User plane ciphering policy

0

spare

User plane integrity protection policy

octet 2

Figure 8.4.22.1: UE PC5 unicast user plane security policy information element

Table 8.4.22.1: UE PC5 unicast user plane security policy information element

User plane integrity protection policy (octet 2, bit 1 to 3)

Bits

3

2

1

0

0

0

User plane integrity protection not needed

0

0

1

User plane integrity protection preferred

0

1

0

User plane integrity protection required

0

1

1

to Spare

1

1

0

1

1

1

Reserved

If the UE receives a user plane integrity protection policy value that the UE does not understand, the UE shall interpret the value as 010 "user plane integrity protection required".

User plane ciphering policy (octet 2, bit 5 to 7)

Bits

7

6

5

0

0

0

User plane ciphering not needed

0

0

1

User plane ciphering preferred

0

1

0

User plane ciphering required

0

1

1

to Spare

1

1

0

1

1

1

Reserved

If the UE receives a user plane ciphering protection policy value that the UE does not understand, the UE shall interpret the value as 010 "user plane ciphering protection required".

Bit 4 and 8 of octet 2 are spare and shall be coded as zero.

8.4.23 Configuration of UE PC5 unicast user plane security protection

The purpose of the configuration of UE PC5 unicast user plane security protection information element is to indicate the agreed configuration for security protection of PC5 user plane data between UEs over the PC5 unicast link.

The configuration of UE PC5 unicast user plane security protection is a type 3 information element with a length of 2 octets.

The configuration of UE PC5 unicast user plane security protection information element is coded as shown in figure 8.4.23.1.1 and table 8.4.23.1.

8

7

6

5

4

3

2

1

configuration of UE PC5 unicast user plane security protection IEI

octet 1

0

spare

User plane ciphering configuration

0

spare

User plane integrity protection configuration

octet 2

Figure 8.4.23.1: Configuration of UE PC5 unicast user plane security protection information element

Table 8.4.23.1: Configuration of UE PC5 unicast user plane security protection information element

User plane integrity protection configuration (octet 2, bit 1 to 3)

Bits

3

2

1

0

0

0

Off

0

0

1

Off or On

0

1

0

On

0

1

1

to Spare

1

1

0

1

1

1

Reserved

User plane ciphering configuration (octet 2, bit 5 to 7)

Bits

7

6

5

0

0

0

Off

0

0

1

Off or On

0

1

0

On

0

1

1

to Spare

1

1

0

1

1

1

Reserved

Bit 4 and 8 of octet 2 are spare and shall be coded as zero.

8.4.24 Re-authentication indication

The purpose of the Re-authentication indication information element is to indication that KNRP needs to be refreshed.

The Re-authentication indication information element is a type 3 information element, with a length of 2 octets.

The Re-authentication indication information element is coded as shown in figure 8.4.24.1 and table 8.4.24.1.

8

7

6

5

4

3

2

1

Re-authentication indication IEI

octet 1

Re-authentication indication contents

octet 2

Figure 8.4.24.1: Re-authentication indication information element

Table 8.4.24.1: Re-authentication indication information element

Re-authentication indication contents (octet 2)

Bits

1

0 Reserved

1 KNRP is requested to be refreshed

Bits 2 to 8 of octet 2 are spare and shall be coded as zero.

8.4.25 Layer-2 ID

The purpose of the layer-2 ID information element is to indicate the layer-2 ID that is used by UE.

The layer-2 ID is a type 3 information element with a length of 4 octets.

The layer-2 ID information element is coded as shown in figure 8.4.25.1 and table 8.4.25.1.

8

7

6

5

4

3

2

1

Layer-2 ID IEI

octet 1

Layer-2 ID

octet 2

octet 4

Figure 8.4.25.1: Layer-2 ID information element

Table 8.4.25.1: Layer-2 ID information element

Layer-2 ID (octet 2 to 4)

This field contains the 24-bit layer-2 ID.