On the use of network coding as a virtual network function in satellite-terrestrial CDNs

This paper describes network coding as a network function. It also discusses how network coding can be easily virtualized and integrated within latest generation architectures dealing with virtual network functions. Network coding actually introduces a new perspective in the field of network function virtualization since it departs from the traditional interpretation of virtual network functions as a generalization of functionality typically implemented in dedicated hardware. It rather refers to a novel network functionality that generalizes and extends classic packet-level end-to-end coding by enabling in-network optimized re-encoding of the transmitted data. This helps improve throughput gains, but can also prove fundamental in the provisioning of non-functional requirements like security and reliability. The paper also focuses on the application of the proposed virtual network coding function to a specific use case related to caching-aided multicast transmissions in hybrid satellite-terrestrial Content Delivery Networks.