Scitags: An Initiative to Improve R&E Networking Visibility

Networking is a key scientific resource, but visibility into R&E network use is challenging. Large users of the R&E network tend to be international collaborations, with data flows that regularly cross international boundaries. This means no single NREN can monitor the flows from end to end. Without this visibility, it is difficult to understand who is using the network and analyze traffic patterns. 

The Scitags initiative, an international project involving the University of Victoria and led by the Research Networking Technical Working Group at CERN, aims to address this situation. The goal is to allow major users of the network to inject information at the packet level defining the purpose of the traffic and the experiment responsible. This is done by using the extended Berkeley Packet Filter (eBPF) to overwrite the flow label field in the IPv6 header. In addition to the direct marking, there is another approach, in which side-channels carrying information about network flows are opened to a dedicated collector machine. Both techniques will be described in detail, along with the motivation, current status, and future plans.