Triangular inter-user equipment coordination for new radio sidelink communications

An apparatus, comprising:

• at least one processor;
• and
• at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus at least to:
• receive, from a first device, a request for inter-user equipment coordination, causing an inter-user equipment coordination (IUC) timer to set a time-period for a response, the IUC timer is set by a side link latency bound inter-UE-coordination (sl-LatencyBoundIUC) report ranging from 3 to 160 slots;
• determine at least one second device to which to forward the request,
• wherein determining the at least one second device is based on:
• a distance between the apparatus and the at least one second device;
• a mobility of the apparatus relative to the at least one second device;
• one or more capabilities of the at least one second device;
• a type of the at least one second device;
• a similarity in an interference situation of the apparatus and the at least one second device;
• a communication state between the apparatus and the at least one second device;
• explicit consent from the at least one second device to receive requests from the apparatus;
• and
• an explicit recommendation of the at least one second device to the apparatus from another device;
• after expiry of the IUC timer, modify the request and forward the modified request to the at least one second device for the second device to provide a response to the request to the first device, the request being modified by an indication related to the forwarding to the at least one second device, wherein the indication comprises:
• transmission information indicating identifiers of the apparatus and the first device;
• information indicating an inability of the apparatus to provide the response to the request from the first device;
• and
• information indicating that the modified request was forwarded from the apparatus to the at least one second device;
• and
• determine to change a cast transmission type of the request to be forwarded, the cast transmission type comprising one of unicast, groupcast, or broadcast,
• wherein the forwarding of the modified request uses the changed cast transmission type, which is different than the cast transmission type used to transmit the request from the first device, and wherein the modified request when forwarded by groupcast or broadcast is restricted to recipients within a configurable range, the configurable range is a distance between the at least one second device and the first device.