Question

A network technician configures a firewall’s ACL to allow outgoing traffic for several popular services such as email and web browsing. However, after the firewall’s deployment, users are still unable to retrieve their emails. Which of the following would BEST resolve this issue?A. Allow the firewall to accept inbound traffic to ports 25, 67, 179, and 3389B. Allow the firewall to accept inbound traffic to ports 80, 110, 143, and 443C. Set the firewall to operate in transparent modeD. Allow the firewall to accept inbound traffic to ports 21, 53, 69, and 123

Answer 1

Answer: (B) Allow the firewall to accept inbound traffic to ports 80, 110, 143, and 443

Explanation:

Port 80 is used by HTTP, 110 by pop3 to retrieve emails from web servers, 143 by imap for internet messaging and 443 is used for TCP for websites using SSL. So if the firewall is allowed to accept inbound traffic to these ports 80,110,143 and 443 then it would be possible to retrieve emails.