Procedures enabling privacy for WTRUs using PC5 communication
A method for changing layer 2 (L2) identifiers (ID)s during an ongoing vehicle-to-everything session between a source wireless transmit/receive unit (WTRU) and a peer WTRU includes communicating between the source and a peer WTRUs based on existing L2 IDs and an existing session ID. On a condition that a trigger event occurs, the source WTRU and the peer WTRU each generate new L2 IDs as well as respective portions of a new session ID. The new L2 IDs are subsequently used along with the new session ID to increase privacy of communication between the source WTRU and the peer WTRU.
1. A method for use in an ongoing vehicle-to-everything session, the method comprising:
communicating between a source wireless transmit/receive unit (WTRU) and a peer WTRU using an existing source WTRU layer 2 identifier (L2 ID), an existing peer WTRU L2 ID, and an existing session identifier (ID) for an existing session having an existing security context;
on a condition that a trigger event occurs:
generating, by the source WTRU, a new source WTRU L2 ID and a new most significant byte (MSB) of a new session ID;
transmitting, by the source WTRU to the peer WTRU, the new source WTRU L2 ID and the new MSB of the new session ID;
receiving, from the peer WTRU, a new peer L2 ID and a new least significant byte (LSB) of the new session ID;
transmitting, by the source WTRU to the peer WTRU, an acknowledgement of the new peer WTRU L2 ID and the new LSB of the new session ID; and
communicating with the peer WTRU using the new source WTRU L2 ID, the new peer WTRU L2 ID, and the new session ID that comprises the new MSB and the new LSB, wherein the communication with the peer WTRU occurs in the existing session using the existing security context.
2. The method of claim 1 , wherein communicating between the source WTRU and the peer WTRU comprises using the existing source WTRU L2 ID, the existing peer WTRU L2 ID, and the existing session ID until after transmitting the acknowledgement.
3. The method of claim 1 , wherein:
transmitting the new source WTRU L2 ID and the MSB of the new session ID to the peer WTRU comprises transmitting using one of a keepalive procedure, a privacy procedure, a PC5 link update procedure, or another communication procedure used between the source WTRU and the peer WTRU.
4. The method of claim 1 , wherein on condition that a trigger event occurs comprises any of:
on condition that a timer expires;
on condition that an upper layer or an application layer of a V2X application requests a new L2 ID;
on condition that the source WTRU moved into a new geographic area;
on condition that the source WTRU received new provisioning parameters from a V2X control function or a V2X application server; or
on condition that the source WTRU received a request from the peer WTRU to change an L2 ID.
5. The method of claim 1 , wherein the session ID is a security context session ID.
6. The method of claim 1 , wherein communicating with the peer (WTRU) comprises communicating on a PC5 reference link.
7. A source wireless transmit/receive unit WTRU comprising circuitry, including a transmitter, a receiver, a processor, and memory, the source WTRU configured to:
communicate, using the transmitter and receiver, between the source WTRU and a peer WTRU using an existing source WTRU layer 2 identifier (L2 ID), an existing peer WTRU L2 ID, and an existing session ID for an existing session having an existing security context;
on a condition that a trigger event occurs:
generate by the source WTRU, a new source WTRU L2 ID, and a new most significant byte (MSB) of a new session ID;
transmit, by the source WTRU to the peer WTRU, the new source WTRU L2 ID and the new MSB of the new session ID;
receive, from the peer WTRU, a new peer WTRU L2 ID and a new least significant byte (LSB) of the new session ID from the peer WTRU;
transmit, by the source WTRU to the peer WTRU, an acknowledgement of the new peer WTRU L2 ID and the new LSB of the new session ID; and
communicate with the peer WTRU using the new source WTRU L2 ID, the new peer WTRU L2 ID, and the new session ID that comprises the new MSB and the new LSB, wherein the communication with the peer WTRU occurs in the existing session using the existing security context.
8. The source WTRU of claim 7 , wherein communicating between the source WTRU and the peer WTRU comprises using the existing source WTRU L2 ID, the existing peer WTRU L2 ID and the existing session ID until after transmitting the acknowledgement.
9. The source WTRU of claim 8 , wherein:
the trigger event comprises at least one of:
an expiration of a timer;
a request for a new L2 ID from an upper layer or an application layer of a V2X application;
a movement of the source WTRU into a new geographic area;
a reception by the source WTRU of new provisioning parameters from a vehicle to everything (V2X) control function or a V2X application server; or
a reception of a request by the source WTRU from the peer WTRU to change an L2 ID.
10. The source WTRU of claim 7 , wherein the source WTRU is configured to:
communicate the new source WTRU L2 ID and the new MSB of the new session ID to the peer WTRU by communicating using one of a keepalive procedure, a privacy procedure, a PC5 link update procedure, or another communication procedure used between the source WTRU and the peer WTRU.
11. The source WTRU of claim 7 , wherein the session ID is a security context session ID.
12. The source WTRU of claim 7 , wherein the source WTRU communicates with the peer WTRU on a PC5 reference link.
13. A non-transitory computer-readable storage medium embodying instructions, which when executed by a computer, cause the computer to perform a method for use in an ongoing vehicle-to-everything (V2X) session, the method comprising:
communicating between a source wireless transmit/receive unit (WTRU) and a peer WTRU using an existing source WTRU layer 2 identifier (L2 ID), an existing peer WTRU L2 ID, and an existing session ID for an existing session having an existing security context;
on a condition that a trigger event occurs:
generating, by the source WTRU, a new source WTRU L2 ID and a new most significant byte (MSB) of a new session ID;
transmitting, by the source WTRU to the peer WTRU, the new source WTRU L2 ID and the new MSB of the new session ID;
receiving, from the peer WTRU, a new peer L2 ID and a new least significant byte (LSB) of the new session ID;
transmitting, by the source WTRU to the peer WTRU, an acknowledgement of the new peer WTRU L2 ID and the new LSB of the new session ID; and
communicating with the peer WTRU using the new source WTRU L2 ID, the new peer WTRU L2 ID, and the new session ID that comprises the new MSB and the new LSB, wherein the communication with the peer WTRU occurs in the existing session using the existing security context.
14. The non-transitory computer-readable storage medium of claim 13 , wherein communicating between the source WTRU and the peer WTRU comprises using the existing source WTRU L2 ID, the existing peer WTRU L2 ID, and the existing session ID until after transmitting the acknowledgement.
15. The non-transitory computer-readable storage medium of claim 13 , wherein:
transmitting the new source WTRU L2 ID and the MSB of the new session ID to the peer WTRU comprises transmitting using one of a keepalive procedure, a privacy procedure, a PC5 link update procedure, or another communication procedure used between the source WTRU and the peer WTRU.
16. The non-transitory computer-readable storage medium of claim 13 , wherein on condition that a trigger event occurs comprises any of:
on condition that a timer expires;
on condition that an upper layer or an application layer of a V2X application requests a new L2 ID;
on condition that the source WTRU moved into a new geographic area;
on condition that the source WTRU received new provisioning parameters from a V2X control function or a V2X application server; or
on condition that the source WTRU received a request from the peer WTRU to change an L2 ID.
17. The non-transitory computer-readable storage medium of claim 13 , wherein the session ID is a security context session ID.