Internet layer security protocol Functions of Internet layer Types of Protocols of Internet layer Architecture of IPsec Modes of IP sec IPsec IKE Protocol Implementation of IKE

1. InternetLayer
Security
Protocol
By Prof. Kirti Ahirrao

2. Index:
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3. Internet Layer Security Protocol :
• It derives its name from its function facilitating internetworking, which is the concept of
connecting multiple networks with each other through gateways.
• Internet Layer is used to provide internetworking.
• It provides group of internetworking methods, protocols and specifications in IP suite
• It is used for transport network packets.
• Internet-layer protocols use IP-based packets.
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4. Function of Internet Layer:
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5. Types of
Protocol in
Internet Layer:
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6. IP sec : Internet
Protocol
Security
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7. IP sec : Internet
Protocol
Security
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8. Architecture of
IP sec:
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9. Architecture of
IP sec:
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10. Architecture of
IP sec:
3.
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11. Modes of Operations (IP sec Operations):
• It is divided into two modes :
1. Transport Mode
2. Tunnel Mode
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12. 1. Transport Mode
• In transport mode, only the payload of the IP packet is usually encrypted or authenticated.
• The routing is intact, since the IP header is neither modified nor encrypted; however, when
the authentication header is used, the IP addresses cannot be modified by network address
translation, as this always invalidates the hash value.
• The transport and application layers are always secured by a hash, so they cannot be
modified in any way, for example by translating the port numbers.
• A means to encapsulate IPsec messages for NAT traversal has been defined
by RFC documents describing the NAT-T mechanism.
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13. 2. Tunnel Mode
• In tunnel mode, the entire IP packet is encrypted and authenticated. It is then
encapsulated into a new IP packet with a new IP header. Tunnel mode is used to
create virtual private networks for network-to-network communications (e.g. between
routers to link sites), host-to-network communications (e.g. remote user access) and host-
to-host communications (e.g. private chat).
• Tunnel mode supports NAT traversal.
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14. Internet Key
Exchange (IKE)
Protocol :
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15. Implementations
of IKE Protocol:
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16. Implementations
of IKE Protocol:
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17. Reference :
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18. Thankyou
Prof. Kirti Ahirrao 18