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SSL VPN by Joseph Steinberg, Tim Speed

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Appendix A. A Review of TCP, IP, and Ports

DARPA and OSI

Overall, there is no formal correlation between the TCP protocol model and the OSI model. But, they are roughly equivalent in the services that are provided. The following diagram shows a comparison between the models:

Protocol Implementation

     

DARPA Layer

   

OSI

 

Process/

Application

FTP

SMTP

TELNET

RFC: 959, 821, 854

TFTP

NFS

SNMP

RFC: 783, 1094

 

Application

Presentation

Session

 

Transport

Transmission Protocol

(TCP) RFC793

User Datagram Protocol (UDP) RFC768

 

Transport

 

Internet

(ARP) Address Resolution

RFC826, 903

(IP) Internet Protocol

RFC791

Internet Control Message Protocol

RFC792

Network

 

Network Interface

Network Interface Cards:

Ethernet, Token Ring

RFC894 ...

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