Image Gallery: TCP/IP Protocol Suite and Security

OSI and DoD Reference Model

Relationship between application layer protocols and services

• HTTP uses TCP port 80 by default
• FTP uses TCP port 21 by default.
• SMTP uses TCP port 25 by default.
• POP3 uses TCP port 110 by default.
• HTTPS uses TCP port 443 by default
• DNS uses UDP port 53
• The Remote Desktop Protocol (RDP) uses TCP port 3389 by default.
• Telnet uses TCP port 23. Windows uses TCP port 445 to access shared resources.

View local listening ports and processes

 Netstat –a

What Windows Firewall does

Prevent ARP spoofing arp firewall

 Arp –a
 Arp –s 192.168.80.1 C8-60-00-2E-6E-1B

AR parsing process:

ICMP is (Internet Control Message Protocol) Internet Control Message Protocol:

• Ping
• pathping

Computer communication process

Network layer header

Using IPSec to protect server security