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In which two ways can an IP packet be cryptographically protected?
The IP Security Architecture (IPsec) provides cryptographic protection for IP datagrams in IPv4 and IPv6 network packets. The protection can include confidentiality, strong integrity of the data, partial sequence integrity (replay protection), and data authentication.
Why is IPsec important?
IPsec is used for protecting sensitive data, such as financial transactions, medical records and corporate communications, as it’s transmitted across the network. It’s also used to secure virtual private networks (VPNs), where IPsec tunneling encrypts all data sent between two endpoints.
What is an advantage of applying ESP before AH in IPsec?
Encapsulating Security Payload ESP also provides the services that AH provides. However, ESP only provides its protections over the part of the datagram that ESP encapsulates. ESP provides optional authentication services to ensure the integrity of the protected packet.
Which mode is used for IP security?
The IPsec standards define two distinct modes of IPsec operation, transport mode and tunnel mode. The key difference between transport and tunnel mode is where policy is applied. In tunnel mode, the original packet is encapsulated in another IP header. The addresses in the other header can be different.
Why do we need SAS between IPsec peers?
The SAs between IPSec peers enable the configured IPSec policy. When a system sends a packet that requires IPSec protection, it looks up the SA in its database, applies the specified processing, and then inserts the SPI from the SA into the IPSec header.
When to perform the output action in SAS?
If both an OUTPUT and a REPLACE or REMOVE statement execute on a given observation, perform the OUTPUT action last to keep the position of the observation pointer correct. This line of code writes the current observation to a SAS data set.
What happens when SAS encounters a compound with multiple expressions?
When SAS encounters a compound WHERE expression (multiple conditions), the software follows rules to determine the order in which to evaluate each expression. When WHERE expressions are combined, SAS processes the conditions in a specific order: The NOT expression is processed first. Then the expressions joined by AND are processed.
What does SAS stand for in security category?
Each SA consists of values such as destination address, a security parameter index (SPI), the IPSec transforms used for that session, security keys, and additional attributes such as IPSec lifetime. The SAs in each peer have unique SPI values that will be recorded in the Security Parameter Databases of the devices.