  We introduce a XOR-based source routing (XSR) scheme as a novel approach to
enable fast forwarding and low-latency communications. XSR uses linear encoding
operation to both 1)~build the path labels of unicast and multicast data
transfers; 2)~perform fast computational efficient routing decisions compared
to standard table lookup procedure without any packet modification all along
the path. XSR specifically focuses on decreasing the complexity of forwarding
router operations. This allows packet switches (e.g, link-layer switch or
router) to perform only simple linear operations over a binary vector label
which embeds the path. XSR provides the building blocks to speed up the
forwarding plane and can be applied to different data planes such as MPLS or
IPv6. Compared to recent approaches based on modular arithmetic, XSR computes
the smallest label possible and presents strong scalable properties allowing to
be deployed over any kind of core vendor or datacenter networks. At last but
not least, the same computed label can be used interchangeably to cross the
path forward or reverse in the context of unicast communication.
