  The Segment Routing (SR) architecture is based on loose source routing. A
list of instructions, called segments can be added to the packet headers, to
influence the forwarding and the processing of the packets in an SR enabled
network. In SRv6 (Segment Routing over IPv6 data plane) the segments are
represented with IPv6 addresses, which are 16 bytes long. There are some SRv6
service scenarios that may require to carry a large number of segments in the
IPv6 packet headers. This can be inefficient due to the overheads of the
segment list, or can even cause processing issues in the crossed nodes due to
the very large header to be processed. In this paper we present the Micro SID
solution for the efficient representation of segment identifiers. With this
solution, the length of the segment list can be drastically reduced.
