# IPSec IPSec (Internet Protocol Security) is a protocol used for securing Internet Protocol (IP) communications by authenticating and encrypting each IP packet in a communication session. IPSec can provide confidentiality, integrity, and authentication for IP datagrams by using cryptographic techniques. It operates at the network layer, and can be used to secure communication between two network endpoints, such as between two routers, two hosts, or between a remote access client and a VPN gateway. IPSec can be used in tunnel mode or transport mode, and supports various encryption and authentication algorithms. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.console.zenlayer.com/glossary/i/ipsec.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.