TCP/IP Networking Guide
Table of Contents
Introduction to TCP/IP
TCP/IP (Transmission Control Protocol/Internet Protocol) is the fundamental suite of protocols that enables communication across networks, including the Internet. It provides end-to-end connectivity and defines how data should be formatted, addressed, transmitted, routed, and received.
Key Features:
- Platform and hardware independent
- Standardized application interfaces
- Connectionless packet delivery
- End-to-end error control
Protocol Stack
TCP/IP Layers
| Layer |
Function |
Protocols |
| Application |
End-user services |
HTTP, FTP, SMTP, DNS |
| Transport |
End-to-end communication |
TCP, UDP |
| Internet |
Addressing and routing |
IP, ICMP, ARP |
| Network Access |
Physical transmission |
Ethernet, Wi-Fi |
IP Addressing
IPv4 Addressing
# IPv4 Address Classes
Class A: 0.0.0.0 to 127.255.255.255 (/8)
Class B: 128.0.0.0 to 191.255.255.255 (/16)
Class C: 192.0.0.0 to 223.255.255.255 (/24)
Subnetting
# Common Subnet Masks
/24 - 255.255.255.0 (256 addresses)
/25 - 255.255.255.128 (128 addresses)
/26 - 255.255.255.192 (64 addresses)
/27 - 255.255.255.224 (32 addresses)
IPv6 Addressing
IPv6 uses 128-bit addresses, written in eight groups of four hexadecimal digits:
2001:0db8:85a3:0000:0000:8a2e:0370:7334
IPv6 Address Types:
- Unicast: Single interface
- Multicast: Group of interfaces
- Anycast: Nearest interface in a group
Common Protocols
TCP (Transmission Control Protocol)
- Connection-oriented protocol
- Reliable data delivery
- Flow control and error checking
- Common ports: 80 (HTTP), 443 (HTTPS), 22 (SSH)
UDP (User Datagram Protocol)
- Connectionless protocol
- Fast, lightweight transmission
- No guaranteed delivery
- Common ports: 53 (DNS), 67/68 (DHCP)
Common Application Protocols
| Protocol |
Port |
Function |
| HTTP |
80 |
Web browsing |
| HTTPS |
443 |
Secure web browsing |
| FTP |
20/21 |
File transfer |
| SSH |
22 |
Secure shell |
| SMTP |
25 |
Email sending |
| DNS |
53 |
Name resolution |
Networking Concepts
Network Types
- LAN (Local Area Network)
- WAN (Wide Area Network)
- MAN (Metropolitan Area Network)
- VPN (Virtual Private Network)
Network Components
- Routers
- Switches
- Firewalls
- Load Balancers
Troubleshooting
Common Tools
# Ping - Test connectivity
ping 8.8.8.8
# Traceroute - Trace packet path
tracert www.google.com
# Netstat - Network statistics
netstat -an
# NSLOOKUP - DNS query
nslookup www.example.com
Common Issues:
- IP address conflicts
- DNS resolution failures
- Routing problems
- Firewall blocking
Best Practices
Network Security
- Implement proper firewall rules
- Use secure protocols (HTTPS, SSH)
- Regular security updates
- Network segmentation
Performance Optimization
- Proper network design
- QoS implementation
- Bandwidth management
- Regular monitoring
Documentation Best Practices:
- Maintain network diagrams
- Document IP addressing scheme
- Keep configuration backups
- Update security policies