EPICS process variables in different subnetworks and different IOCs   without the use of the CaGateway
  This technical document describes the comparison of the EPICS PV gateway and a new solution based on relay of UDP packets using the UDP-HELPER switch feature, iptables and a C program. The solution can be applied on environments that contain multiple sub-networks and a number of IOCs on the same host or multiple IOCs on the same sub-network. 
Rodrigo Bongers
cs.NI