7 Message functional definition and contents

24.5873GPPProtocol aspectsRelease 17Stage 3TSVehicle-to-Everything (V2X) services in 5G System (5GS)

7.1 Overview

This clause contains the definition and contents of the messages used in the procedures described in the present document.

7.2 Provisioning of parameters for V2X configuration signalling messages

7.2.1 UE policy provisioning request

7.2.1.1 Message definition

The UE POLICY PROVISIONING REQUEST message is sent by the UE to the PCF to request the PCF to manage V2XP, ProSeP or both, see table 7.2.1.1.1

Message type: UE POLICY PROVISIONING REQUEST

Significance: dual

Direction: UE to network

Table 7.2.1.1.1: UE POLICY PROVISIONING REQUEST message content

IEI

Information Element

Type/Reference

Presence

Format

Length

PTI

Procedure transaction identity

TS 24 501 [4] clause 9.6

M

V

1

UE POLICY PROVISIONING REQUEST message identity

UE policy delivery service message type

TS 24 501 [4] clause D.6.1

M

V

1

Requested UE policies

Requested UE policies

8.3.2

M

LV

2-3

7.2.2 UE policy provisioning reject

7.2.2.1 Message definition

The UE POLICY PROVISIONING REJECT message is sent by the PCF to the UE to report that the PCF rejects reques, ProSeP or both t to manage V2XP, see table 7.2.2.1.1

Message type: UE POLICY PROVISIONING REJECT

Significance: dual

Direction: network to UE

Table 7.2.2.1.1: UE POLICY PROVISIONING REJECT message content

IEI

Information Element

Type/Reference

Presence

Format

Length

PTI

Procedure transaction identity

TS 24 501 [4] clause 9.6

M

V

1

UE POLICY PROVISIONING REJECT message identity

UE policy delivery service message type

TS 24 501 [4] clause D.6.1

M

V

1

UPDS cause

UPDS cause

8.3.1

M

V

1

7.3 V2X communication over PC5 signalling messages

7.3.1 Direct link establishment request

7.3.1.1 Message definition

This message is sent by a UE to another peer UE to establish a direct link. See table 7.3.1.1.1.

Message type: DIRECT LINK ESTABLISHMENT REQUEST

Significance: dual

Direction: UE to peer UE

Table 7.3.1.1.1: DIRECT LINK ESTABLISHMENT REQUEST message content

IEI

Information Element

Type/Reference

Presence

Format

Length

DIRECT LINK ESTABLISHMENT REQUEST message identity

PC5 signalling message type

8.4.1

M

V

1

Sequence number

Sequence number

8.4.2

M

V

1

V2X service identifiers

V2X service identifier

8.4.3

M

LV

5-253

Source user info

Application layer ID

8.4.4

M

LV

3-253

UE security capabilities

UE security capabilities

8.4.14

M

LV

3-9

UE PC5 unicast signalling security policy

UE PC5 unicast signalling security policy

8.4.15

M

V

1

74

Key establishment information container

Key establishment information container

8.4.12

O

TLV-E

4-n

53

Nonce_1

Nonce

8.4.13

O

TV

17

54

MSBs of KNRP-sess ID

MSBs of KNRP-sess ID

8.4.16

O

TV

2

28

Target user info

Application layer ID

8.4.4

O

TLV

4-254

52

KNRP ID

KNRP ID

8.4.17

O

TV

5

7.3.1.2 Target user info

The UE shall include this IE if it has received the target UE’s application layer ID from upper layers or if the destination layer-2 ID is the unicast layer-2 ID of target UE.

7.3.1.3 Key establishment information container

The UE shall include this IE if the UE PC5 unicast signalling security policy is set to "signalling integrity protection required" or "signalling integrity protection preferred".

7.3.1.4 Nonce_1

The UE shall include this IE if the UE PC5 unicast signalling security policy is set to "signalling integrity protection required" or "signalling integrity protection preferred".

7.3.1.5 MSBs of KNRP-sess ID

The UE shall include this IE if the UE PC5 unicast signalling security policy is set to "signalling integrity protection required" or "signalling integrity protection preferred".

7.3.1.6 KNRP ID

The UE may include this IE if it has an existing KNRP for the target UE.

7.3.2 Direct link establishment accept

7.3.2.1 Message definition

This message is sent by a UE to another peer UE to accept the received DIRECT LINK ESTABLISHMENT REQUEST message. See table 7.3.2.1.1.

Message type: DIRECT LINK ESTABLISHMENT ACCEPT

Significance: dual

Direction: UE to peer UE

Table 7.3.2.1.1: DIRECT LINK ESTABLISHMENT ACCEPT message content

IEI

Information Element

Type/Reference

Presence

Format

Length

DIRECT LINK ESTABLISHMENT ACCEPT message identity

PC5 signalling message type

8.4.1.

M

V

1

Sequence number

Sequence number

8.4.2

M

V

1

Source user info

Application layer ID

8.4.4

M

LV

3-253

QoS flow descriptions

PC5 QoS flow descriptions

8.4.5

M

LV-E

5-65537

Configuration of UE PC5 unicast user plane security protection

Configuration of UE PC5 unicast user plane security protection

8.4.23

M

V

1

57

IP address configuration

IP address configuration

8.4.6

O

TV

2

58

Link local IPv6 address

Link local IPv6 address

8.4.7

O

TV

17

7.3.2.2 IP address configuration

The UE shall include this IE if IP communication is used.

7.3.2.3 Link local IPv6 address

The UE shall include this IE if IP communication is used and the IP address configuration is set to "IPv6 address allocation not supported".

7.3.3 Void

7.3.4 Direct link modification request

7.3.4.1 Message definition

This message is sent by the UE to another peer UE to initiate the direct link modification procedure. See table 7.3.4.1.1.

Message type: DIRECT LINK MODIFICATION REQUEST

Significance: dual

Direction: UE to peer UE

Table 7.3.4.1.1: DIRECT LINK MODIFICATION REQUEST message content

IEI

Information Element

Type/Reference

Presence

Format

Length

DIRECT LINK MODIFICATION REQUEST message identity

PC5 signalling message type

8.4.1

M

V

1

Sequence number

Sequence number

8.4.2

M

V

1

Link modification operation code

Link modification operation code

8.4.8

M

V

1

QoS flow descriptions

PC5 QoS flow descriptions

8.4.5

M

LV-E

5-65537

7.3.5 Direct link modification accept

7.3.5.1 Message definition

This message is sent by the UE to another peer UE to indicate that the link modification request is accepted. See table 7.3.5.1.1

Message type: DIRECT LINK MODIFICATION ACCEPT

Significance: dual

Direction: UE to peer UE

Table 7.3.5.1.1: DIRECT LINK MODIFICATION ACCEPT message content

IEI

Information Element

Type/Reference

Presence

Format

Length

DIRECT LINK MODIFICATION ACCEPT message identity

PC5 signalling message type

8.4.1

M

V

1

Sequence number

Sequence number

8.4.2

M

V

1

79

QoS flow descriptions

PC5 QoS flow descriptions

8.4.5

O

TLV-E

6-65538

7.3.5.2 QoS flow descriptions

The UE shall include this IE if the PC5 unicast link modification procedure is to:

a) add new PC5 QoS flow(s) to the existing PC5 unicast link;

b) modify PC5 QoS parameters of the existing PC5 QoS flow(s);

c) associate new V2X service(s) with existing PC5 QoS flow(s); or

d) remove V2X service(s) from existing PC5 QoS flow(s).

7.3.6 Direct link release request

7.3.6.1 Message definition

This message is sent by the UE to another peer UE to initiate the direct link release procedure. See table 7.3.6.1.1.

Message type: DIRECT LINK RELEASE REQUEST

Significance: dual

Direction: UE to peer UE

Table 7.3.6.1.1: DIRECT LINK RELEASE REQUEST message content

IEI

Information Element

Type/Reference

Presence

Format

Length

DIRECT LINK RELEASE REQUEST message identity

PC5 signalling message type

8.4.1

M

V

1

Sequence number

Sequence number

8.4.2

M

V

1

PC5 signalling protocol cause

PC5 signalling protocol cause

8.4.9

M

V

1

MSB of KNRP ID

MSB of KNRP ID

8.4.20

M

V

2

7.3.7 Direct link release accept

7.3.7.1 Message definition

This message is sent by the UE to another peer UE to indicate that the link release request is accepted. See table 7.3.7.1.

Message type: DIRECT LINK RELEASE ACCEPT

Significance: dual

Direction: UE to peer UE

Table 7.3.7.1: DIRECT LINK RELEASE ACCEPT message content

IEI

Information Element

Type/Reference

Presence

Format

Length

DIRECT_LINK_RELEASE ACCEPT message identity

PC5 signalling message type

8.4.1

M

V

1

Sequence number

Sequence number

8.4.2

M

V

1

LSB of KNRP ID

LSB of KNRP ID

8.4.21

M

V

2

7.3.8 Direct link keepalive request

7.3.8.1 Message definition

This message is sent by a UE to another peer UE when a PC5 unicast link keep-alive procedure is initiated. See table 7.3.8.1.1.

Message type: DIRECT LINK KEEPALIVE REQUEST

Significance: dual

Direction: UE to peer UE

Table 7.3.8.1.1: DIRECT LINK KEEPALIVE REQUEST message content

IEI

Information Element

Type/Reference

Presence

Format

Length

DIRECT LINK KEEPALIVE REQUEST message identity

PC5 signalling message type

8.4.1.

M

V

1

Sequence number

Sequence number

8.4.2

M

V

1

Keep-alive counter

Keep-alive counter

8.4.10

M

V

4

55

Maximum inactivity period

Maximum inactivity period

8.4.11

O

TV

5

7.3.8.2 Maximum inactivity period

The UE may include this IE to indicate its maximum inactivity period to the peer UE.

7.3.9 Direct link keepalive response

7.3.9.1 Message definition

This message is sent by a UE to another peer UE to respond to a DIRECT LINK KEEPALIVE REQUEST message. See table 7.3.9.1.1.

Message type: DIRECT LINK KEEPALIVE RESPONSE

Significance: dual

Direction: UE to peer UE

Table 7.3.9.1.1: DIRECT LINK KEEPALIVE RESPONSE message content

IEI

Information Element

Type/Reference

Presence

Format

Length

DIRECT LINK KEEPALIVE RESPONSE message identity

PC5 signalling message type

8.4.1.

M

V

1

Sequence number

Sequence number

8.4.2

M

V

1

Keep-alive counter

Keep-alive counter

8.4.10

M

V

4

7.3.10 Direct link authentication request

7.3.10.1 Message definition

This message is sent by a UE to another peer UE when a PC5 unicast link authentication procedure is initiated. See table 7.3.10.1.1.

Message type: DIRECT LINK AUTHENTICATION REQUEST

Significance: dual

Direction: UE to peer UE

Table 7.3.10.1.1: DIRECT LINK AUTHENTICATION REQUEST message content

IEI

Information Element

Type/Reference

Presence

Format

Length

DIRECT LINK AUTHENTICATION REQUEST message identity

PC5 signalling message type

8.4.1.

M

V

1

Sequence number

Sequence number

8.4.2

M

V

1

Key establishment information container

Key establishment information container

8.4.12

M

LV-E

3-n

7.3.11 Direct link authentication response

7.3.11.1 Message definition

This message is sent by a UE to another peer UE to respond to a DIRECT LINK AUTHENTICATION REQUEST message. See table 7.3.11.1.1.

Message type: DIRECT LINK AUTHENTICATION RESPONSE

Significance: dual

Direction: UE to peer UE

Table 7.3.11.1.1: DIRECT LINK AUTHENTICATION RESPONSE message content

IEI

Information Element

Type/Reference

Presence

Format

Length

DIRECT LINK AUTHENTICATION RESPONSE message identity

PC5 signalling message type

8.4.1.

M

V

1

Sequence number

Sequence number

8.4.2

M

V

1

Key establishment information container

Key establishment information container

8.4.12

M

LV-E

3-n

7.3.12 Direct link authentication reject

7.3.12.1 Message definition

This message is sent by a UE to another peer UE to reject a DIRECT LINK AUTHENTICATION REQUEST message. See table 7.3.12.1.1.

Message type: DIRECT LINK AUTHENTICATION REJECT

Significance: dual

Direction: UE to peer UE

Table 7.3.12.1.1: DIRECT LINK AUTHENTICATION REJECT message content

IEI

Information Element

Type/Reference

Presence

Format

Length

DIRECT LINK AUTHENTICATION REJECT message identity

PC5 signalling message type

8.4.1.

M

V

1

Sequence number

Sequence number

8.4.2

M

V

1

PC5 signalling protocol cause value

PC5 signalling protocol cause value

8.4.9

M

V

1

7.3.13 Direct link security mode command

7.3.13.1 Message definition

This message is sent by a UE to another peer UE when a PC5 unicast link security mode control procedure is initiated. See table 7.3.13.1.1.

Message type: DIRECT LINK SECURITY MODE COMMAND

Significance: dual

Direction: UE to peer UE

Table 7.3.13.1.1: DIRECT LINK SECURITY MODE COMMAND message content

IEI

Information Element

Type/Reference

Presence

Format

Length

DIRECT LINK SECURITY MODE COMMAND message identity

PC5 signalling message type

8.4.1.

M

V

1

Sequence number

Sequence number

8.4.2

M

V

1

Selected security algorithms

Selected security algorithms

8.4.18

M

V

1

UE security capabilities

UE security capabilities

8.4.14

M

LV

3-9

59

UE PC5 unicast signalling security policy

UE PC5 unicast signalling security policy

8.4.15

O

TV

2

55

Nonce_2

Nonce

8.4.13

O

TV

17

52

LSBs of KNRP-sess ID

LSBs of KNRP-sess ID

8.4.19

O

TV

2

74

Key establishment information container

Key establishment information container

8.4.12

O

TLV-E

4-n

62

MSBs of KNRP ID

MSBs of KNRP ID

8.4.20

O

TV

3

7.3.13.2 Nonce_2

The UE shall include this IE if the selected integrity protection algorithms is not the null integrity protection algorithm.

7.3.13.3 LSBs of KNRP-sess ID

The UE shall include this IE if the selected integrity protection algorithms is not the null integrity protection algorithm.

7.3.13.4 Key establishment information container

The UE shall include this IE if the UE has derived a new KNRP and the authentication method used to generate KNRP requires sending information to complete the authentication procedure.

7.3.13.5 MSBs of KNRP ID

The UE shall include this IE if the UE has derived a new KNRP.

7.3.13.6 UE PC5 unicast signalling security policy

The UE shall include this IE if the DIRECT LINK SECURITY MODE COMMAND message is triggered by the DIRECT LINK ESTABLISHMENT REQUEST message. The content of the IE is the same as the content of UE PC5 unicast signalling security policy IE in the received DIRECT LINK ESTABLISHMENT REQUEST message in order to provide protection against bidding down attacks.

7.3.14 Direct link security mode complete

7.3.14.1 Message definition

This message is sent by a UE to another peer UE to respond to a DIRECT LINK SECURITY MODE COMMAND message. See table 7.3.14.1.1.

Message type: DIRECT LINK SECURITY MODE COMPLETE

Significance: dual

Direction: UE to peer UE

Table 7.3.14.1.1: DIRECT LINK SECURITY MODE COMPLETE message content

IEI

Information Element

Type/Reference

Presence

Format

Length

DIRECT LINK SECURITY MODE COMPLETE message identity

PC5 signalling message type

8.4.1.

M

V

1

Sequence number

Sequence number

8.4.2

M

V

1

QoS flow descriptions

PC5 QoS flow descriptions

8.4.5

M

LV-E

6-n

UE PC5 unicast user plane security policy

UE PC5 unicast user plane security policy

8.4.22

M

V

1

57

IP address configuration

IP address configuration

8.4.6

O

TV

2

58

Link local IPv6 address

Link local IPv6 address

8.4.7

O

TV

17

52

LSBs of KNRP ID

LSBs of KNRP ID

8.4.21

O

TV

3

7.3.14.2 IP address configuration

The UE shall include this IE if IP communication is used and the PC5 unicast link security mode control procedure was triggered during a PC5 unicast link establishment procedure.

7.3.14.3 Link local IPv6 address

The UE shall include this IE if IP communication is used, the IP address configuration is set to "IPv6 address allocation not supported" and the PC5 unicast link security mode control procedure was triggered during a PC5 unicast link establishment procedure.

7.3.14.4 LSBs of KNRP ID

The UE shall include this IE if a new KNRP was derived.

7.3.15 Direct link security mode reject

7.3.15.1 Message definition

This message is sent by a UE to another peer UE to reject a DIRECT LINK SECURITY MODE COMMAND message. See table 7.3.15.1.1.

Message type: DIRECT LINK SECURITY MODE REJECT

Significance: dual

Direction: UE to peer UE

Table 7.3.15.1.1: DIRECT LINK SECURITY MODE REJECT message content

IEI

Information Element

Type/Reference

Presence

Format

Length

DIRECT LINK SECURITY MODE REJECT message identity

PC5 signalling message type

8.4.1.

M

V

1

Sequence number

Sequence number

8.4.2

M

V

1

PC5 signalling protocol cause

PC5 signalling protocol cause

8.4.9

M

V

1

7.3.16 Direct link rekeying request

7.3.16.1 Message definition

This message is sent by a UE to another peer UE when a PC5 unicast link re-keying procedure is initiated. See table 7.3.16.1.1.

Message type: DIRECT LINK REKEYING REQUEST

Significance: dual

Direction: UE to peer UE

Table 7.3.16.1.1: DIRECT LINK REKEYING REQUEST message content

IEI

Information Element

Type/Reference

Presence

Format

Length

DIRECT LINK REKEYING REQUEST message identity

PC5 signalling message type

8.4.1.

M

V

1

Sequence number

Sequence number

8.4.2

M

V

1

UE security capabilities

UE security capabilities

8.4.14

M

LV

3-9

74

Key establishment information container

Key establishment information container

8.4.12

O

TLV-E

4-n

53

Nonce_1

Nonce

8.4.13

O

TV

17

54

MSBs of KNRP-sess ID

MSBs of KNRP-sess ID

8.4.16

O

TV

2

56

Re-authentication indication

Re-authentication indication

8.4.24

O

TV

2

7.3.16.2 Key establishment information container

The UE shall include this IE if the null integrity protection algorithm is not in use.

7.3.16.3 Nonce_1

The UE shall include this IE if the null integrity protection algorithm is not in use.

7.3.16.4 MSBs of KNRP-sess ID

The UE shall include this IE if the null integrity protection algorithm is not in use.

7.3.16.5 Re-authentication indication

The UE shall include this IE if the UE wants to derive a new KNRP.

7.3.17 Direct link rekeying response

7.3.17.1 Message definition

This message is sent by a UE to another peer UE to respond to a DIRECT LINK REKEYING REQUEST message. See table 7.3.17.1.1.

Message type: DIRECT LINK REKEYING RESPONSE

Significance: dual

Direction: UE to peer UE

Table 7.3.17.1.1: DIRECT LINK REKEYING RESPONSE message content

IEI

Information Element

Type/Reference

Presence

Format

Length

DIRECT LINK REKEYING RESPONSE message identity

PC5 signalling message type

8.4.1.

M

V

1

Sequence number

Sequence number

8.4.2

M

V

1

7.3.18 Direct link identifier update request

7.3.18.1 Message definition

This message is sent by a UE to another peer UE to initiate the direct link identifier procedure. See table 7.3.18.1.1.

Message type: DIRECT LINK IDENTIFIER UPDATE REQUEST

Significance: dual

Direction: UE to peer UE

Table 7.3.18.1.1: DIRECT LINK IDENTIFIER UPDATE REQUEST message content

IEI

Information Element

Type/Reference

Presence

Format

Length

DIRECT LINK IDENTIFIER UPDATE REQUEST message identity

PC5 signalling message type

8.4.1

M

V

1

Sequence number

Sequence number

8.4.2

M

V

1

MSB of KNRP-sess ID

MSB of KNRP-sess ID

8.4.16

M

V

1

Source layer-2 ID

Layer-2 ID

8.4.25

M

V

3

57

Source user info

Application layer ID

8.4.4

O

TLV

4-254

58

Source link local IPv6 address

Link local IPv6 address

8.4.7

O

TV

17

7.3.18.2 Source user info

This IE is included when the initiating UE receives a new application layer ID.

7.3.18.3 Source link local IPv6 address

This IE is included when the link local IPv6 address changes at the initiating UE.

7.3.19 Direct link identifier update accept

7.3.19.1 Message definition

This message is sent by the UE to another peer UE to indicate that the link identifier update request is accepted. See table 7.3.19.1.1.

Message type: DIRECT LINK IDENTIFIER UPDATE ACCEPT

Significance: dual

Direction: UE to peer UE

Table 7.3.19.1.1: DIRECT LINK IDENTIFIER UPDATE ACCEPT message content

IEI

Information Element

Type/Reference

Presence

Format

Length

DIRECT LINK IDENTIFIER UPDATE ACCEPT message identity

PC5 signalling message type

8.4.1

M

V

1

Sequence number

Sequence number

8.4.2

M

V

1

LSB of KNRP-sess ID

LSB of KNRP-sess ID

8.4.19

M

V

1

MSB of KNRP-sess ID

MSB of KNRP-sess ID

8.4.16

M

V

1

Source layer-2 ID

Layer-2 ID

8.4.25

M

V

3

Target layer-2 ID

Layer-2 ID

8.4.25

M

V

3

28

Target user info

Application layer ID

8.4.4

O

TLV

4-254

59

Target link local IPv6 address

Link local IPv6 address

8.4.7

O

TV

17

57

Source user info

Application layer ID

8.4.4

O

TLV

4-254

58

Source link local IPv6 address

Link local IPv6 address

8.4.7

O

TV

17

7.3.19.2 Target user info

This IE is included if the target UE receives the Source user info IE in the DIRECT LINK IDENTIFIER UPDATE REQUEST message.

7.3.19.3 Target link local IPv6 address

This IE is included if the target UE receives the Source link local IPv6 address IE in the DIRECT LINK IDENTIFIER UPDATE REQUEST message.

7.3.19.4 Source user info

This IE is included when the application layer ID changes at the target UE and the target UE receives a new application layer ID from the upper layers.

7.3.19.5 Source link local IPv6 address

This IE is included when the link local IPv6 address changes at the target UE and the target UE receives a new Link local IPv6 address from the upper layers.

7.3.20 Direct link identifier update ack

7.3.20.1 Message definition

This message is sent by the initiating UE to target UE to indicate that the initiating UE has received target UE’s accept message. See table 7.3.20.1.1.

Message type: DIRECT LINK IDENTIFIER UPDATE ACK

Significance: dual

Direction: UE to peer UE

Table 7.3.20.1.1: DIRECT LINK IDENTIFIER UPDATE ACK message content

IEI

Information Element

Type/Reference

Presence

Format

Length

DIRECT LINK IDENTIFIER UPDATE ACK message identity

PC5 signalling message type

8.4.1

M

V

1

Sequence number

Sequence number

8.4.2

M

V

1

LSB of KNRP-sess ID

LSB of KNRP-sess ID

8.4.19

M

V

1

Target layer-2 ID

Layer-2 ID

8.4.25

M

V

3

28

Target user info

Application layer ID

8.4.4

O

TLV

4-254

59

Target link local IPv6 address

Link local IPv6 address

8.4.7

O

TV

17

7.3.20.2 Target user info

This IE is included when the initiating UE receives the Source user info IE in the DIRECT LINK IDENTIFIER UPDATE ACCEPT message.

7.3.20.3 Target link local IPv6 address

This IE is included when the initiating UE receives the Source link local IPv6 address IE in the DIRECT LINK IDENTIFIER UPDATE ACCEPT message.

7.3.21 Direct link identifier update reject

7.3.21.1 Message definition

This message is sent by the target UE to initiating UE to indicate that the link identifier update request is not accepted. See table 7.3.21.1.1.

Message type: DIRECT LINK IDENTIFIER UPDATE REJECT

Significance: dual

Direction: UE to peer UE

Table 7.3.21.1.1: DIRECT LINK IDENTIFIER UPDATE REJECT message content

IEI

Information Element

Type/Reference

Presence

Format

Length

DIRECT LINK IDENTIFIER UPDATE REJECT message identity

PC5 signalling message type

8.4.1

M

V

1

Sequence number

Sequence number

8.4.2

M

V

1

PC5 signalling protocol cause

PC5 signalling protocol cause

8.4.9

M

V

1

7.3.22 Direct link modification reject

7.3.22.1 Message definition

This message is sent by the UE to another peer UE to indicate that the link modification request is not accepted. See table 7.3.22.1.1.

Message type: DIRECT LINK MODIFICATION REJECT

Significance: dual

Direction: UE to peer UE

Table 7.3.22.1.1: DIRECT LINK MODIFICATION REJECT message content

IEI

Information Element

Type/Reference

Presence

Format

Length

DIRECT LINK MODIFICATION REJECT message identity

PC5 signalling message type

8.4.1

M

V

1

Sequence number

Sequence number

8.4.2

M

V

1

PC5 signalling protocol cause

PC5 signalling protocol cause

8.4.9

M

V

1

7.3.23 Direct link establishment reject

7.3.23.1 Message definition

This message is sent by the UE to another peer UE to indicate that the link establishment request is not accepted. See table 7.3.23.1.1.

Message type: DIRECT LINK ESTABLISHMENT REJECT

Significance: dual

Direction: UE to peer UE

Table 7.3.23.1.1: DIRECT LINK ESTABLISHMENT REJECT message content

IEI

Information Element

Type/Reference

Presence

Format

Length

DIRECT LINK ESTABLISHMENT REJECT message identity

PC5 signalling message type

8.4.1

M

V

1

Sequence number

Sequence number

8.4.2

M

V

1

PC5 signalling protocol cause

PC5 signalling protocol cause

8.4.9

M

V

1

7.3.24 Direct link authentication failure

7.3.24.1 Message definition

This message is sent by a UE to another peer UE to reject a DIRECT LINK AUTHENTICATION RESPONSE message. See table 7.3.24.1.1.

Message type: DIRECT LINK AUTHENTICATION FAILURE

Significance: dual

Direction: UE to peer UE

Table 7.3.24.1.1: DIRECT LINK AUTHENTICATION FAILURE message content

IEI

Information Element

Type/Reference

Presence

Format

Length

DIRECT LINK AUTHENTICATION FAILURE message identity

PC5 signalling message type

8.4.1.

M

V

1

Sequence number

Sequence number

8.4.2

M

V

1

74

Key establishment information container

Key establishment information container

8.4.12

O

TLV-E

4-n

7.3.24.2 Key establishment information container

The UE shall include this IE if it is provided by upper layers.