Dell S3048-ON, Configuration Manual

Page: 358 / 1036

Internet Protocol Security (IPSec)
Internet protocol security (IPSec) is an end-to-end security scheme for protecting IP communications by authenticating and encrypting all
packets in a communication session. Use IPSec between hosts, between gateways, or between hosts and gateways.
IPSec is compatible with Telnet and FTP protocols. It supports two operational modes: Transport and Tunnel.
• Transport mode — (default) Use to encrypt only the payload of the packet. Routing information is unchanged.
• Tunnel mode — Use to encrypt the entire packet including the routing information of the IP header. Typically used when creating virtual
private networks (VPNs).
NOTE: Due to performance limitations on the control processor, you cannot enable IPSec on all packets in a communication
session.
IPSec uses the following protocols:
• Authentication Headers (AH) — Disconnected integrity and origin authentication for IP packets
• Encapsulating Security Payload (ESP) — Confidentiality, authentication, and data integrity for IP packets
• Security Associations (SA) — Necessary algorithmic parameters for AH and ESP functionality
IPSec supports the following authentication and encryption algorithms:
• Authentication only:
•
MD5
• SHA1
• Encryption only:
•
3DES
• CBC
• DES
• ESP Authentication and Encryption:
•
MD5 & 3DES
• MD5 & CBC
• MD5 & DES
• SHA1 & 3DES
• SHA1 & CBC
• SHA1 & DES
Configuring IPSec
The following sample configuration shows how to configure FTP and telnet for IPSec.
1 Define the transform set.
CONFIGURATION mode
crypto ipsec transform-set myXform-seta esp-authentication md5 esp-encryption des
2 Define the crypto policy.
CONFIGURATION mode
20
358 Internet Protocol Security (IPSec)