This paper presents the popular backup/archival service developed and operated in Poland by members of the PIONIER network consortium and its example application for outsourcing of the archival of the network traffic in the national academic network. The service is built upon the National Data Storage (NDS) system architecture deployed in the redundant, high-end, geographically distributed infrastructure of servers, network and data storage systems built within the confines of the PLATON project. The details of the NDS architecture and its features are discussed in the paper including the system components, their functionality and the system scalability aspects. The paper also presents how the NDS architecture is deployed in the data storage infrastructure of the PLATON project, with an extensive usage of servers and storage virtualization technologies. We discuss how the NDS system instantiation allows for flexible set up of the multiple instances of the popular backup/archival service, which can address various, often contradictory requirements of the service users, while sharing a common pool of physical resources. As an example the system set up for outsourcing the archival of the PIONIER network traffic is presented.