goatwu1993
Taiwan. Backend/DevOps. Python.
OSI 7 Layres
- Application Layer (Layer 7)
- Presentation Layer (Layer 6)
- Session Layer (Layer 5)
- Transport Layer (Layer 4)
- Network Layer (Layer 3)
- IP Address
- Router, Layer 3 Switch
- Data Link Layer (Layer 2)
- Ethernet, 802.11(Wi-Fi), MAC Address
- Layer 2 Switch
- Physical Layer (Layer 1)
TCP/IP protocols
- HTTP
- Hyper Text Transport Protocol
- TCP Port 80
- HTTPS
- Hyper Text Transport Protocol Secure
- TCP Port 443
- FTP
- File Transfer Protocol
- TCP Port 21
- Telnet
- Telecommunication Protocol
- TCP Port 23
- SMTP
- Simple Mail Transfer Protocol
- TCP port 25
- For email
- DNS
- TFTP
- Trivial File Transfer Protocol
- UDP port 69
- Not secure. Should only be used in private net.
- RADIUS
- Remote Authentication Dial-In User Service
- UDP Port : 1812 (authentication) & 1813(accounting)
- Code
- Access-Request
- Access-Accept
- Access-Reject
- Access-Challenge