A network administrator is troubleshooting an issue where hosts on the management subnet cannot establish secure web connections to a server at . Upon reviewing the inbound interface settings on the router, the administrator inspects the following Access Control List (ACL):
text 10 permit tcp 10.10.10.0 0.0.0.255 host 10.20.30.50 eq 80 20 deny ip any any
When attempting to access the server's web control portal via `https://10.20.30.50`, connection attempts time out. Which of the following identifies the root cause of this failure?
- The ACL permits HTTP traffic on port 80 rather than HTTPS traffic on port 443, causing HTTPS packets to match the deny rule.Answer
- BThe workstations on the management subnet are configured with a default gateway residing on a different IP subnet.
- CThe router requires a separate statutory outbound ACL to allow TCP port 22 traffic before port 443 traffic can be processed.
- DThe switch infrastructure is missing an IP helper address to route Layer 2 broadcast frames across VLAN boundaries.
Answer
The ACL rule permits TCP port 80 (HTTP) instead of TCP port 443 (HTTPS), causing secure web connections to be blocked by the subsequent deny rule.
The correct option correctly identifies that HTTPS uses TCP port 443. Because rule 10 specifically matches `eq 80` (HTTP), packets destined for port 443 skip rule 10 and hit rule 20 (`deny ip any any`), resulting in a connection timeout.
Step-by-Step Solution
Key Concept
ACL Port Filtering and Sequence Evaluation
Estimated Time:1m 30s