Methods, architectures, apparatuses and systems directed to improved service continuity for out of range proximity wireless transmit/receive devices
Procedures, methods, architectures, apparatuses, systems, devices, and computer program products directed to improved service continuity in connection with wireless transmit/receive devices not remaining within proximity/range of each other to continue device-to-device (D2D) communications are provided.
1 . A method implemented in a first wireless transmit/receive unit, WTRU, the method comprising:
determining a state of sidelink communications between the first WTRU and a second WTRU;
transmitting first information to a first network element of a core network, wherein the first information indicates the state of the sidelink communications, a first identifier associated with the first WTRU and a second identifier associated with the second WTRU for sidelink communications;
transmitting second information to a second network element of the core network, wherein the second information indicates a description of a traffic flow associated with the sidelink communications and a request to establish a protocol data unit session;
transmitting outbound traffic of the traffic flow associated with the sidelink communications and an address of the first WTRU to an application server pursuant to the protocol data unit session; and
receiving inbound traffic of the traffic flow associated with the sidelink communications from the application server pursuant to the protocol data unit session.
2 . The method of claim 1 , wherein determining a state of sidelink communications between the first WTRU and the second WTRU comprises:
monitoring for keep alive transmissions; and
determining the state of the sidelink communications based on a number of keep alive transmissions received within a time period.
3 . The method of the claim 2 , wherein the state is a first value if the number of keep alive transmissions received within the time period fails to satisfy a first threshold, and wherein the state is a second value if the number of keep alive transmissions received within the time period satisfies one of the first threshold and a second threshold different from the first threshold.
4 . The method of claim 3 , wherein the first value indicates the sidelink communications with the second WTRU are not or no longer viable.
5 . The method of claim 1 , further comprising:
receiving an address of the second WTRU from the application server; and
transmitting outbound traffic of the traffic flow associated with the sidelink communications using the address of the second WTRU.
6 . The method of claim 1 , wherein at least one of:
the first and second network elements comprise an access and mobility management function and a session management function, respectively;
the first and second network elements are the same network element; and
each of the first and second network elements comprises one of a session management function and an access and mobility management function.
7 . The method of claim 1 , wherein the first identifier comprises any of an application layer identifier of the first WTRU and a layer-2 identifier of first the WTRU, and wherein the second identifier comprises any of an application layer identifier of the second WTRU and a layer-2 identifier of the second WTRU.
8 . The method claim 1 , wherein the description of a traffic flow associated with the sidelink communications comprises any of a PC5 quality of service flow identifier and one or more quality of service rules.
9 . The method of claim 1 , wherein at least one of:
the first information is transmitted as, or in, in a notification message; and
the first information is transmitted as, or in, any of a non-access stratum message and a radio resource control message.
10 . The method of claim 1 , further comprising:
receiving, from the second network element of the core network, information to trigger the WTRU to request to establish the protocol data unit session.
11 . A first wireless transmit/receive unit, WTRU, comprising circuitry, including a transmitter, receiver, a processor and memory, configured to:
determine a state of sidelink communications between the first WTRU and a second WTRU;
transmit first information to a first network element of a core network, wherein the first information indicates the state of the sidelink communications, a first identifier associated with the first WTRU and a second identifier associated with the second WTRU for sidelink communications;
transmit second information to a second network element of the core network, wherein the second information indicates a description of a traffic flow associated with the sidelink communications and a request to establish a protocol data unit session;
transmit outbound traffic of the traffic flow associated with the sidelink communications and an address of the first WTRU to the application server pursuant to the protocol data unit session; and
receive inbound traffic of the traffic flow associated with the sidelink from the application server pursuant to the protocol data unit session.
12 . The first WTRU of claim 11 , wherein the circuitry is configured to:
monitor for keep alive transmissions; and
determine the state of the sidelink communications based on a number of keep alive transmissions received within a time period.
13 . The first WTRU of claim 11 , wherein the circuitry is configured to:
receive an address of the second WTRU from the application server; and
transmit outbound traffic of the traffic flow associated with the sidelink communications using the address of the second WTRU.
14 . The first WTRU of claim 11 , wherein the state is a first value if the number of keep alive transmissions received within the time period fails to satisfy a first threshold, and wherein the state is a second value if the number of keep alive transmissions received within the time period satisfies one of the first threshold and a second threshold different from the first threshold.
15 . The first WTRU of claim 14 , wherein the first value indicates the sidelink communications with the second WTRU are not or no longer viable.
16 . The first WTRU of claim 11 , wherein at least one of:
the first and second network elements comprise an access and mobility management function and a session management function, respectively;
the first and second network elements are the same network element; and
each of the first and second network elements comprises one of a session management function and an access and mobility management function.
17 . The first WTRU of claim 11 , wherein the first identifier comprises any of an application layer identifier of the first WTRU and a layer-2 identifier of first the WTRU, and wherein the second identifier comprises any of an application layer identifier of the second WTRU and a layer-2 identifier of the second WTRU.
18 . The first WTRU of claim 11 , wherein the description of a traffic flow associated with the sidelink communications comprises any of a PC5 quality of service flow identifier and one or more quality of service rules.
19 . The first WTRU of claim 11 , wherein at least one of:
the first information is transmitted as, or in, a notification message; and
the first information is transmitted as, or in, any of a non-access stratum message and a radio resource control message.
20 . The first WTRU of claim 11 , wherein the circuitry is configured to:
receive, from the second network element of the core network, information to trigger the WTRU to request to establish the protocol data unit session.