A Common Public Radio Interface (CPRI) link involves using a protocol stack having a CPRI layer and an emulation layer to emulate a point to point link, to enable the CPRI link to operate over a packet switched network. The emulation layer can be a pseudowire emulation which encapsulates multiple CPRI frames in a packet with overhead. A multiplexing layer such as Internet Protocol (IP) or Multiprotocol Label Switching (MPLS) can be used, for sending the packet over an Ethernet network. The usual need for a point to point infrastructure for the CPRI link can be avoided and the CPRI link can be implemented over more complex but usually cheaper packet networks, thus reducing costs or enabling more widespread application over existing packet networks. This applies whether the packet network is dedicated to the CPRI link, or shared with other packets. It can be useful for distributed radio base stations.