Selecting SSH's standard port | LinuC Level 1 102 Exam original practice question

1.07.1Basic

Connect to an SSH server listening on its standard TCP port.

The server port has not been changed.

Which destination port is used?

Hint 1: Focus on protocol roles

Separate reliable transport, datagram transport, IP control messages, and name resolution before comparing the choices.

Hint 2: Key terms

Review the short definitions of transport protocols, control messages, and name resolution involved.

SSH: A protocol for encrypted remote login and secure forwarding.
Telnet: An older remote-terminal protocol that does not encrypt the session.
FTP: A protocol for transferring files.
TCP port: A numbered endpoint that delivers traffic to a TCP service.

Detailed explanation

Incorrect21

Incorrect. 21/tcp is FTP control.

Incorrect23

Incorrect. 23/tcp is Telnet.

Correct22

Correct. 22/tcp is SSH's standard port.

Incorrect25

Incorrect. 25/tcp is SMTP.

An example you can run in a temporary verification environment.

getent services ssh | sed -n '1p'

ssh 22/tcpを示すサービスデータベース行

Foundation review

The part of an IP address that identifies the network rather than a host.

TCP and UDP provide different delivery, reliability, and connection semantics.

A numbered endpoint used to deliver traffic to a network service.

Question IDKL-102-947

EnvironmentLinux NSS servicesデータベース / 外部通信なし

Last technical review2026-08-13

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