quick notes

📝 Syslog Severity Levels (0–7)

Order (0 = highest severity, 7 = lowest):

0 – Emergency

1 – Alert

2 – Critical

3 – Error

4 – Warning

5 – Notice

6 – Informational

7 – Debug

🔑 Mnemonic:

👉 “Every Awesome Cat Eats Wet Noodles In Dens.”

• Every → Emergency (0)
• Awesome → Alert (1)
• Cat → Critical (2)
• Eats → Error (3)
• Wet → Warning (4)
• Noodles → Notice (5)
• In → Informational (6)
• Dens → Debug (7)

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🛡️ Zero Trust Architecture (ZTA)

Core Components:

• Policy Engine → Decides if access should be allowed (brains of ZTA).
• Policy Administrator → Sets up and manages the rules.
• Policy Enforcement Point (PEP) → Executes the decision (enforces allow/deny).
• Subject System → The user/device trying to connect.

🔑 Memory Trick:

👉 “Engine Decides, Admin Writes, Enforcement Executes, Subject Requests.”

• Engine = Policy Engine (decision-maker).
• Admin = Policy Administrator (rule-setter).
• Enforcement = Enforcement Point (gatekeeper).
• Subject = User/Device making the request.

🔌 Common Ports (Network+ Must Know)

| Port | Protocol / Service | Notes | | --- | --- | --- | | 20/21 | FTP (File Transfer Protocol) | 20 = data, 21 = control. Cleartext. | | 22 | SSH / SFTP / SCP | Encrypted remote login & file transfer. | | 23 | Telnet | Remote login, insecure (plaintext). | | 25 | SMTP (Simple Mail Transfer Protocol) | Mail transfer (legacy). | | 53 | DNS (Domain Name System) | UDP = queries, TCP = zone transfers. | | 67/68 | DHCP (Dynamic Host Config Protocol) | 67 = server, 68 = client. | | 69 | TFTP (Trivial File Transfer Protocol) | Lightweight, no authentication. | | 80 | HTTP | Unencrypted web. | | 110 | POP3 (Post Office Protocol v3) | Retrieve mail (legacy). | | 143 | IMAP (Internet Message Access Protocol) | Retrieve/sync mail. | | 161/162 | SNMP (Simple Network Management Protocol) | 161 = requests, 162 = traps. | | 389 | LDAP (Lightweight Directory Access Protocol) | Directory services (AD, etc.). | | 443 | HTTPS (HTTP Secure) | Encrypted web traffic. | | 445 | SMB (Server Message Block) | Windows file/printer sharing. | | 514 | Syslog | Log forwarding (UDP). | | 636 | LDAPS | Secure LDAP (TLS/SSL). | | 1433 | Microsoft SQL Server | Database connections. | | 3306 | MySQL | Database connections. | | 3389 | RDP (Remote Desktop Protocol) | Windows remote GUI. | | 5060/5061 | SIP (Session Initiation Protocol) | VoIP signaling (5060 = UDP/TCP, 5061 = TLS). |

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✅ Exam Tips

• Memorize mail protocols (25 = SMTP, 110 = POP3, 143 = IMAP).
• SSH vs Telnet: 22 = secure, 23 = insecure.
• DNS (53) = UDP mostly, TCP sometimes.
• RDP = 3389, HTTPS = 443 (most commonly tested).
• DHCP = 67/68 (server/client).

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🔑 Memory Trick (for big ones):

👉 “Some People Feel That Sending Data Helps Improve Security.”

• SSH – 22
• POP3 – 110
• FTP – 20/21
• Telnet – 23
• SMTP – 25
• DNS – 53
• HTTP – 80
• IMAP – 143
• SNMP – 161

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⚡ Sample Question:

A user reports they cannot connect via RDP to a remote server. Which port should the administrator check is open?

→ 3389