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Network+ Exam

Remote Access Ports and Protocols

October 29, 2025

  • #network+

Remote Access Ports and Protocols

Build an manage systems and networks from across the network. Allows admins and users to run progras from afar

SSH : Secure shell - protocol used for secure remote logn over a secure netork. Operates over port 22.

SSH is creating a secure encrypted tunnel that cna operate text based commands from a remote server.

Telnet - Operates oer port 23, allows one computer to longin remotly to another computer. Telnet lacks encryption. SSH replaced Telnet. never use it.

RDP: Propritary protocol that was developed by ‘Microsoft to provide users with a GUI to to connect to another computer over a network onnection. 3389

data encrption smart card authentication, bandwidth reduction mechanisims.

RDP and SSh are critical to managing modern networks.

What these do (in one line)

  • SSH (Secure Shell) — secure CLI remote login/tunneling over 22/TCP.
  • Telnet — legacy, insecure CLI remote login over 23/TCP (don’t use on real networks).
  • RDP (Remote Desktop Protocol) — Microsoft GUI remote access over 3389/TCP with encryption, smart‑card auth, bandwidth reduction.

Must Know (Ports show up a lot)

  • SSH = 22, Telnet = 23, RDP = 3389. (All listed under N10‑009 1.4 ports table.)

Key Differences (fast compare)

  • Security
    • SSH: Encrypted channel + strong auth.
    • Telnet: Plain text (credentials and data). Avoid.
    • RDP: Encrypted session; supports smart cards and bandwidth reduction.
  • Use case
    • SSH: Admin CLI on Linux/Unix/network gear; can tunnel SFTP/port‑forwarding.
    • Telnet: Only for labs/legacy when encryption isn’t required (exam will flag it as wrong in prod).
    • RDP: Full Windows GUI remote control.

Exam Tips

  • Ports: If the question smells like “secure CLI,” pick SSH/22; “legacy CLI,” Telnet/23; “Windows GUI,” RDP/3389.
  • Security: “Plain‑text remote login?” → Telnet (bad). “Encrypted remote management?” → SSH or RDP depending on CLI vs GUI.
  • Association: SFTP rides SSH on port 22 (often paired in questions).

Memory Tricks

  • “22 is secure too (SSH)”, “23 is dirty (Telnet)”, “RDP has 3–3–8–9 windows” (think Windows GUI boxes).

Quick Checks (Common Questions)

  • Q: Which protocol gives you a secure terminal into a router over the internet?

    A: SSH (22).

  • Q: A packet capture shows user/pass in clear text during remote login—what protocol?

    A: Telnet (23).

  • Q: Need full desktop on a remote Windows Server with smart‑card login—what/port?

    A: RDP (3389).

Flashcards (optional)

  • Front: SSH default port

    Back: 22/TCP (secure CLI/tunnel).

  • Front: Telnet default port + risk

    Back: 23/TCP; plain text/insecure.

  • Front: RDP default port + two features

    Back: 3389/TCP; encryption, smart‑card auth (also bandwidth reduction mechanisms).

30‑Second Drill

  • SSH 22 ✅
  • Telnet 23 ❌ (insecure)
  • RDP 3389 🪟 (GUI, encrypted)

Want me to turn this into a one‑page cram sheet with a mini port map?