Palo Alto Networks Certified Cybersecurity Entry-level Technician (PCCET)Network SecurityEasy
A network administrator is troubleshooting connectivity issues between two internal subnets. The administrator observes that devices on subnet A can ping devices on subnet B, but devices on subnet B cannot initiate connections to services on subnet A. Further investigation reveals that a stateless firewall is separating the two subnets. What is the most likely reason for this one-way communication issue?
- AThe DHCP server is misconfigured for subnet B.
- BA routing loop exists between the two subnets.
- CThe stateless firewall is blocking return traffic from subnet A.
- DIncorrect IP addressing on subnet B devices.
Show answer & explanationAnswer & explanation
Correct answer: C. The stateless firewall is blocking return traffic from subnet A.
Stateless firewalls only inspect individual packets and do not maintain information about the state of a connection. If a rule allows traffic from A to B but no explicit rule allows return traffic from B to A, the return packets will be dropped.
Why the other options are wrong
- A. DHCP misconfiguration would affect IP assignment, not necessarily create one-way communication after IPs are obtained.
- B. A routing loop would typically result in packet loss or delays for traffic in both directions, not just one-way blocking.
- D. Incorrect IP addressing would likely prevent any communication, not just one-way.
Stateless Firewall
A firewall that examines each packet individually, without regard to the state of the connection to which the packet belongs.
- Does not track active connections.
- Requires explicit rules for both inbound and outbound traffic.
- Less resource-intensive but less secure and flexible than stateful firewalls.
Memory trick: Stateless walls see packets, not conversations. Stateful walls remember the chat.