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The TCP/IP Guide  9  TCP/IP Lower-Layer (Interface, Internet and Transport) Protocols (OSI Layers 2, 3 and 4)       9  TCP/IP Internet Layer (OSI Network Layer) Protocols            9  Internet Protocol (IP/IPv4, IPng/IPv6) and IP-Related Protocols (IP NAT, IPSec, Mobile IP)                 9  IP Security (IPSec) Protocols

IP Security (IPSec) Protocols 1 2 3 IPSec General Operation, Components and Protocols

Overview of IPSec Services and Functions

IPSec is not a single protocol, but rather a set of services and protocols that provide a complete security solution for an IP network. These services and protocols combine to provide various types of protection. Since IPSec works at the IP layer, it can provide these protections for any higher layer TCP/IP application or protocol without the need for additional security methods, which is a major strength. Some of the kinds of protection services offered by IPSec include:

• Encryption of user data for privacy.
  
  
• Authentication of the integrity of a message to ensure that it is not changed en route.
  
  
• Protection against certain types of security attacks, such as replay attacks.
  
  
• The ability for devices to negotiate the security algorithms and keys required to meet their security needs.
  
  
• Two security modes, tunnel and transport, to meet different network needs.

IP Security (IPSec) Protocols 1 2 3 IPSec General Operation, Components and Protocols