220-1101 Question 59
Single answer22 – Secure Shell (SSH)A technician needs to securely manage a Linux server at a remote branch office over the internet. The branch firewall team reports that they have allowed only the standard port required for encrypted remote terminal access. The technician can ping the server's public IP address, but a remote desktop client will not connect. Which tool should the technician use to access the server's command line securely?
- A
SSH client
- B
Telnet client
- C
RDP client
- D
FTP client
Show answer and explanation
Correct answer: A
Explanation
The best answer is an SSH client because SSH is the standard secure protocol for remote command-line administration and uses TCP port 22 by default. In real-world support environments, technicians commonly use SSH to manage Linux and network devices remotely when secure shell access is required. This aligns with common best practices to avoid insecure protocols such as Telnet for administrative access over untrusted networks. Vendor and standards documentation consistently identifies SSH as the secure replacement for Telnet for remote shell access, while RDP is intended for remote GUI sessions and FTP is intended for file transfers rather than terminal administration.
- A. Correct.
Correct. SSH (Secure Shell) uses TCP port 22 by default and is designed to provide encrypted remote command-line access to systems such as Linux servers. In this scenario, the firewall allows the standard port for encrypted remote terminal access, which matches SSH.
- B. Incorrect.
Incorrect. Telnet can provide remote command-line access, but it is not secure because it transmits data, including credentials, in plaintext. Telnet commonly uses TCP port 23, not the secure standard port referenced in the scenario.
- C. Incorrect.
Incorrect. RDP is used for remote graphical desktop access, typically to Windows systems, and uses TCP port 3389 by default. The scenario specifically points to encrypted remote terminal access on the standard SSH port rather than a graphical remote desktop connection.
- D. Incorrect.
Incorrect. FTP is used for file transfers rather than interactive remote command-line administration. Standard FTP also does not provide secure terminal access and typically uses TCP ports 20 and 21, so it does not fit the scenario.