Security+ ยท 3.0 Security Architecture
TCP three-way handshake
How TCP connections establish: client sends SYN, server answers SYN+ACK, client acknowledges with ACK. Until the handshake completes, no data flows.
How this shows up at NCAE
`nmap -Pn -p 80` sends SYNs and looks at responses. 'Connection refused' = you got a RST (there's no service). 'Timeout' = you got nothing (firewall dropped). Different symptoms, different fixes.
Error patterns associated with this term
Competition failures where this Security+ concept applies.
| Pts missed | Count | Service | Status | Message | Teams | |
|---|---|---|---|---|---|---|
| 26.4 | 19 | SMB Read | partial | SMB operation failed: Failed to retrieve backslide.data on files: Unable to ope. | 4/13 | details |