On a 10Base2 (thin Ethernet) LAN, your client PC can access several servers but cannot access the server named RED, while other clients can. What is the most likely cause of this selective connectivity problem?

Introduction / Context:
Connectivity issues that affect only a single remote server, while other servers remain reachable, often point to software or configuration mismatches rather than physical-layer faults. On legacy Ethernet like 10Base2, shared-media problems usually impact many or all devices, not just one target.

Given Data / Assumptions:

• Your client can reach several servers on the same LAN segment.
• Only the server named RED is unreachable from your client, but others can reach it.
• The cabling is 10Base2 (coaxial bus topology), where breaks generally disrupt many nodes downstream.

Concept / Approach:
If physical issues (cable break, termination) existed, multiple systems would typically lose connectivity. An IRQ or NIC hardware fault would likely prevent all network access. High collision rates would degrade the entire segment, not a single client-server pair. A protocol mismatch (for example, your client only has NetBEUI, while RED only speaks TCP/IP) explains why other servers (which support your protocol) work, but RED (which requires a different protocol) does not.

Step-by-Step Solution:

Verification / Alternative check:
Run protocol-specific tests (for example, ping for TCP/IP). If ping fails but NetBIOS browsing works only for other servers, it reinforces a protocol mismatch diagnosis.

Why Other Options Are Wrong:

• IRQ misconfiguration would likely break all network access, not just one server.
• A cable break or poor termination would affect many hosts on the bus segment.
• Excessive collisions slow everyone, not a single destination.

Common Pitfalls:
Assuming any single-host issue must be physical. Always compare installed protocol stacks across client and target server.

Final Answer:
There is a protocol mismatch between your client computer and RED.