Warning

Interface whitelist will be deprecated in future versions of Fast DDS. The use of the new interfaces allowlist is recommended.

6.10. Interface Whitelist

Using Fast DDS, it is possible to limit the network interfaces used by TCP Transport and UDP Transport. This is achieved by adding the interfaces to the interfaceWhiteList field in the TCPTransportDescriptor or UDPTransportDescriptor. Thus, the communication interfaces used by the DomainParticipants whose TransportDescriptorInterface defines an interfaceWhiteList is limited to the interfaces’ addresses defined in that list, therefore avoiding the use of the rest of the network interfaces available in the system. The interfaces in interfaceWhiteList can be specified both by IP address or interface name. For example:

• Interface whitelist filled with IP address:

  C++XML

  DomainParticipantQos qos;
  
  // Create a descriptor for the new transport.
  auto tcp_transport = std::make_shared<TCPv4TransportDescriptor>();
  
  // Add loopback to the whitelist by IP address
  tcp_transport->interfaceWhiteList.emplace_back("127.0.0.1");
  
  // Link the Transport Layer to the Participant.
  qos.transport().user_transports.push_back(tcp_transport);
  
  // Avoid using the builtin transports
  qos.transport().use_builtin_transports = false;
  

• Interface whitelist filled with interface names:

  C++XML

  DomainParticipantQos qos;
  
  // Create a descriptor for the new transport.
  auto tcp_transport = std::make_shared<TCPv4TransportDescriptor>();
  
  // Add loopback to the whitelist by interface name
  tcp_transport->interfaceWhiteList.emplace_back("lo");
  
  // Link the Transport Layer to the Participant.
  qos.transport().user_transports.push_back(tcp_transport);
  
  // Avoid using the builtin transports
  qos.transport().use_builtin_transports = false;
  

Important

If none of the values in the transport descriptor’s whitelist match the interfaces on the host, then all the interfaces in the whitelist are filtered out and therefore no communication will be established through that transport.

Warning

The interface whitelist feature applies to network interfaces. Therefore, it is only available on TCP Transport and UDP Transport.