---
name: "fast_ipsec"
section: "4"
platform: "linux"
package: "freebsd-manpages"
version: "6.0-5"
release: "Debian 4.0 (Etch)"
platforms: ["linux"]
url: "https://new.carta.tech/fast_ipsec"
---

# fast\_ipsec(4)

hardware-accelerated IP Security Protocols

## NAME

**Fast IPsec** – hardware-accelerated IP Security Protocols

## SYNOPSIS

**options FAST\_IPSEC** **device crypto**

-

  *net.inet.esp.enable*

-

  *net.inet.ah.enable*

-

  *net.inet.ipcomp.enable*

## DESCRIPTION

IPsec is a set of protocols, ESP (for Encapsulating Security Payload) AH (for Authentication Header), and IPComp (for IP Payload Compression Protocol) that provide security services for IP datagrams. **Fast IPsec** is an experimental implementation of these protocols that uses the [crypto(4)](/crypto/4.md) subsystem to carry out cryptographic operations. This means, in particular, that cryptographic hardware devices are employed whenever possible to optimize the performance of these protocols.

In general, the **Fast IPsec** implementation is intended to be compatible with the KAME IPsec implementation. This documentation concentrates on differences from that software. The user should refer to [ipsec(4)](/ipsec/4.md) for basic information on setting up and using these protocols.

System configuration requires the [crypto(4)](/crypto/4.md) subsystem. When the **Fast IPsec** protocols are configured for use, all protocols are included in the system. To selectively enable/disable protocols, use [sysctl(8)](/sysctl/8.md).

## DIAGNOSTICS

To be added.

## SEE ALSO

[crypto(4)](/crypto/4.md), [ipsec(4)](/ipsec/4.md), [setkey(8)](/setkey/8.md), [sysctl(8)](/sysctl/8.md)

## HISTORY

The protocols draw heavily on the OpenBSD implementation of the IPsec protocols. The policy management code is derived from the KAME implementation found in their IPsec protocols. The **Fast IPsec** protocols first appeared in FreeBSD 5.0.

## BUGS

There is presently no support for IPv6.

The IPcomp protocol support does not work.

Certain legacy authentication algorithms are not supported because of issues with the [crypto(4)](/crypto/4.md) subsystem.

This documentation is incomplete.