IoT promises a world where physical objects are continuously reachable and addressable over the Internet. In supply chain management, RFID technology has become a cornerstone for tracking goods as they move between locations. However, a fundamental gap exists between the physical movement of tagged objects and their persistent network presence. When a passive RFID tag moves between readers, any associated network state is lost, making it impossible to maintain a continuous, addressable identity for the object.

This project proposes that a VM acting as the network counterpart of a physical object should migrate along with the object as it moves through the supply chain. A key motivation is that latency-critical local decisions can be made by the VM at the point of reader encounter, without incurring the round-trip delay of consulting a central server. Crucially, when the VM computes a decision or issues a compliance certificate at a checkpoint, it can instruct the local reader to write that result back onto the physical tag. The tag thereby becomes a physically embodied audit trail, carrying verified state from each checkpoint independently of network infrastructure. The VM and the tag act as complementary state carriers: the VM provides rich networked computation, while the tag provides a physically resilient record that survives even if network continuity is interrupted.

Passive RFID tags cannot host a network stack. However, as established in prior work, a reader can assign an IPv6 address to a VM acting as the tag's network counterpart, constructing the address from the tag's EPC using CGAs. The challenge arises when the object moves to a new reader: the network prefix changes, the old address becomes unreachable, and network continuity is lost.

This project addresses the following core research question: Can a live VM migration, triggered by and synchronised with the physical movement of an RFID-tagged object between readers, maintain continuous network reachability and preserve computational state across subnet boundaries, while using write-to-tag operations to maintain a physically embodied audit trail on the tag itself?

Three interrelated problems must be solved. How can the VM's network identity be cryptographically bound to the tag's EPC such that the identity remains stable as the VM migrates? How can reader events trigger VM migration in a timely manner, given that a passive tag can only report data at the moment of a reader encounter? And how can the underlying network, using SDN techniques such as OpenFlow, ensure that the VM's IP address remains routable after migration to a host on a different subnet?

The project will proceed in three phases, building on preliminary work already undertaken in constructing IPv6 addresses from EPC identifiers using CGA techniques.

• In the first phase, a testbed will be designed consisting of at least two RFID readers connected to separate network subnets, each associated with a hypervisor host running Xen. An SDN layer using Open vSwitch and an OpenFlow controller will provide a virtual L2 overlay across the subnets, ensuring the VM's IP address remains routable regardless of which host it resides on. The VM's IPv6 address will be constructed using the CGA scheme derived from the object's EPC, cryptographically binding the network identity to the physical tag. Tags with write capability, such as EPC Class 1 Generation 2 tags, will be used to support write-back operations.
• In the second phase, a triggering and orchestration mechanism will be implemented. When the tagged object enters the field of a new reader, a reader event will signal the orchestration layer to initiate a live Xen migration of the VM to the host associated with the new reader. Upon successful migration, the VM will perform any pending local computation and write a signed checkpoint record back onto the tag, updating the physically embodied audit trail.
• In the third phase, the end-to-end system will be evaluated. Success will be measured by the ability to continuously ping the object's IPv6 address throughout its physical journey, with computational state and audit trail integrity preserved across reader handovers. Metrics of interest will include migration latency, decision response time compared to a centralised server baseline, and the completeness and integrity of the audit trail written to the tag. Results will be discussed in the context of Mobile IPv6 and HIP based alternatives as identified in the related literature.