Introducing TCP/IP Networks ICSSCADA Practice Questions (Page 2)

Questions 6–10

1. 6application · easy

   A new historian server is added to the OT network. The server's hostname is 'historian-01', but when engineers try to connect using that hostname, the connection fails. They can connect using the server's IP address. Which service is most likely misconfigured?

   • ADHCP
   • BNAT
   • CARP
   • DDNS
   Reveal Solution Discussion Select an answer first
2. 7expert · hard

   An OT network uses a private IP range (10.0.0.0/8) and connects to the corporate IT network through a firewall that performs NAT. A new application on the OT side needs to receive unsolicited inbound connections from a specific IT host. The security team wants to minimize the attack surface. Which NAT configuration should be used?

   • AUse port address translation (PAT) to map the OT application's private IP and port to a single public IP, but allow all inbound traffic on that port from any source.
   • BDisable NAT and route the OT private IP directly through the firewall to the IT host.
   • CUse dynamic NAT with a pool of public addresses, and allow any IT host to connect to the OT application.
   • DCreate a static one-to-one NAT mapping for the OT application's IP address, and restrict the firewall rule to the specific IT host's IP and the required port.
   Reveal Solution Discussion Select an answer first
4. 8application · medium

   A SCADA engineer needs to transfer a large firmware update file to a PLC over an unreliable wireless link. The update must be verified for integrity. Which transport protocol should be used and why?

   • ATCP, because it uses a fixed header size of 20 bytes, which reduces overhead.
   • BUDP, because it is faster and has lower overhead for large file transfers.
   • CUDP, because it supports multicast, which is needed for firmware updates.
   • DTCP, because it provides reliable delivery and error checking through sequence numbers and checksums.
   Reveal Solution Discussion Select an answer first
5. 9foundation · easy

   In IP routing, what does a routing metric represent?

   • AThe IP address of the next hop
   • BThe number of packets forwarded
   • CThe MAC address of the destination
   • DThe cost or preference of a route
   Reveal Solution Discussion Select an answer first
6. 10application · medium

   A utility company uses a NAT device to allow a remote engineer to access a historian server on the SCADA network. The historian has a private IP address. The engineer initiates a connection from the corporate network. Which NAT type is required for this inbound connection?

   • AStatic NAT with a one-to-one mapping to a public IP address
   • BOverlapping NAT to translate the historian's private address to another private address
   • CDynamic NAT with a pool of public IP addresses
   • DPort Address Translation (PAT) with an outbound-only rule
   Reveal Solution Discussion Select an answer first