More and more devices are becoming connected. These connected devices can be MTC devices such as smart meters, but increasingly all kinds of consumer electronic devices (e.g. photo cameras, navigation devices, e-books, hifi equipment, TVs) are connected. Where Machine-Type Communication is generally client server based, many consumer electronic devices also communicate with other consumer electronic devices. For example a photo camera can communicate with a printer, or a media server can communicate with hi-fi equipment. It may be of interest for the cellular industry to support infrastructure based discovery and communications between connected devices, i.e. without the need for intermediate network servers. In this context, the objective of the present document is to study:

• Potential enhancements to support secure discovery of Ues of interest
• Potential enhancements to support secure optimized end-to-end data communication between Ues via the 3GPP infrastructure
• Potential enhancements derived from user requirements for identification in communication between Ues
• Potential interactions of data communication between devices with LIPA and SIPTO

UEs may represent functions/capabilities provided by non-3GPP devices in order to support interworking. However, discovery of, or end-to-end data communication with, non-3GPP devices themselves is out of scope. Potential enhancements will be studied through the definition of use cases. From these use cases, potential requirements are identified. For potential requirements identified, if any, it will be determined what is the best way to approach normative specification.

The following documents contain provisions which, through reference in this text, constitute provisions of the present document.

• References are either specific (identified by date of publication, edition number, version number, etc.) or non specific.
• For a specific reference, subsequent revisions do not apply.
• For a non-specific reference, the latest version applies. In the case of a reference to a 3GPP document (including a GSM document), a non-specific reference implicitly refers to the latest version of that document in the same Release as the present document.