# US 2025/0098013 A1 · Method for ue-to-ue relay reselection security and privacy

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 2025/0098013 A1
- Document ID: US20250098013A1
- Status: Published application
- Kind: A1
- Application number: 18/958,981
- Filed: 2024-11-25
- Published: 2025-03-20
- Earliest claimed: 2023-04-04
- Assignees: InterDigital Patent Holdings, Inc.
- Applicants: InterDigital Patent Holdings, Inc.
- Inventors: Samir FERDI; Michelle PERRAS; Ulises OLVERA-HERNANDEZ
- Web page: https://patentgrep.com/patent/US20250098013A1

## CPC

- H04W 12/041: Key generation or derivation
- H04W 76/20: Manipulation of established connections
- H04W 12/02: Protecting privacy or anonymity, e.g. protecting personally identifiable information [PII]
- H04W 12/0471: Key exchange
- H04W 12/069: using certificates or pre-shared keys
- H04W 12/106: Packet or message integrity
- H04W 76/14: Direct-mode setup
- H04W 76/15: Setup of multiple wireless link connections
- H04L 69/14: Multichannel or multilink protocols
- H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72)
- H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M)

## Abstract

A relay WTRU may establish a connection between a first and a second WTRU. The relay WTRU may include sending, to the second WTRU, a LMR message received from the first WTRU, the LMR message including a request for a release of the connection, and sending, to the first WTRU, a LMA message received from the second WTRU, where the LMA message includes an acceptance of the release of the connection, The relay WTRU may include sending, to the second WTRU, a link release request message received from the first WTRU including one or more new MSBs of a new KNRP ID and sending, to the first WTRU, a link release response message received from the second WTRU, the link release response message including one or more new LSBs of the new KNRP ID, where the new KNRP ID is formed by combining the new MSBs and the new LSBS.

## Claims

### Claim 1

A method performed by a relay wireless transmit receive unit (WTRU), the method comprising:
establishing a unicast connection between a first WTRU and a second WTRU;
sending, to the second WTRU, a link modification request (LMR) message received from the first WTRU, the LMR message including a request for a coordinated release of the unicast connection between the first WTRU and the second WTRU;
sending, to the first WTRU, a link modification accept (LMA) message received from the second WTRU, the LMA message including an acceptance of the coordinated release of the unicast connection between the first WTRU and the second WTRU;
sending, to the second WTRU, a link release request message received from the first WTRU, the link release request message including one or more new most significant bytes (MSBs) of a new Key NR ProSe identifier (KNRP ID); and
sending, to the first WTRU, a link release response message received from the second WTRU, the link release response message including one or more new least significant bytes (LSBs) of the new KNRP ID, wherein the new KNRP ID is formed by combining the one or more new MSBs and the one or more new LSBs.

### Claim 2 (depends on 1)

The method of claim 1, further comprising establishing the unicast connection between the first WTRU and the second WTRU based on an existing KNRP ID, and wherein the existing KNRP ID is different from the new KNRP ID.

### Claim 3 (depends on 2)

The method of claim 2, wherein the existing KNRP ID is the same at the first WTRU and the second WTRU.

### Claim 4 (depends on 2)

The method of claim 2, wherein the existing KNRP ID is discarded once the new KNRP ID is formed.

### Claim 5 (depends on 1)

The method of claim 1, further comprising determining to maintain an initial connection between the first WTRU and the second WTRU based on a configuration parameter that controls usage of simultaneous connections, wherein the configuration parameter includes a maximum number of simultaneous connections allowed for a ProSe service.

### Claim 6

A relay wireless transmit receive unit (WTRU) comprising:
processor circuitry; and
a transceiver operatively coupled to the processor circuitry and configured to:
establish a unicast connection between a first WTRU and a second WTRU;
send, to the second WTRU, a link modification request (LMR) message received from the first WTRU, the LMR message including a request for a coordinated release of the unicast connection between the first WTRU and the second WTRU;
send, to the first WTRU, a link modification accept (LMA) message received from the second WTRU, the LMA message including an acceptance of the coordinated release of the unicast connection between the first WTRU and the second WTRU;
send, to the second WTRU, a link release request message received from the first WTRU, the link release request message including one or more new most significant bytes (MSBs) of a new Key NR ProSe identifier (KNRP ID); and
send, to the first WTRU, a link release response message received from the second WTRU, the link release response message including one or more new least significant bytes (LSBs) of the new KNRP ID, wherein the new KNRP ID is formed by combining the one or more new MSBs and the one or more new LSBs.

### Claim 7 (depends on 6)

The first WTRU of claim 6, wherein the transceiver is further configured to establish the unicast connection between the first WTRU and the second WTRU based on an existing KNRP ID, and wherein the existing KNRP ID is different from the new KNRP ID.

### Claim 8 (depends on 7)

The relay WTRU of claim 7, wherein the existing KNRP ID is the same at the first WTRU and the second WTRU.

### Claim 9 (depends on 7)

The relay WTRU of claim 7, wherein the existing KNRP ID is discarded once the new KNRP ID is formed.

### Claim 10 (depends on 6)

The relay WTRU of claim 6, wherein the processor circuitry is further configured to maintain an initial connection between the first WTRU and the second WTRU based on a configuration parameter that controls usage of simultaneous connections, wherein the configuration parameter includes a maximum number of simultaneous connections allowed for a ProSe service.