See 4.3.18 for a description of this threat. Several of the resulting threats are covered in their own sections, but a key counter measure is to utilise encryption as described in 5.2.5. The denial of service is difficult to counter, but OPC UA supports IPv6, which can counter many of the network infrastructure attacks. It is important that network security features are utilized and that network infrastructure be part of regular security Audits and network configuration is reviewed.