Dell S3048-ON, Configuration Manual

Page: 570 / 1036

You decide the set of IPsec protocols that are employed for authentication and encryption and the ways in which they are employed. When
you correctly implement and deploy IPsec, it does not adversely affect users or hosts. AH and ESP are designed to be cryptographic
algorithm-independent.
OSPFv3 Authentication Using IPsec: Configuration Notes
OSPFv3 authentication using IPsec is implemented according to the specifications in RFC 4552.
• To use IPsec, configure an authentication (using AH) or encryption (using ESP) security policy on an interface or in an OSPFv3 area.
Each security policy consists of a security policy index (SPI) and the key used to validate OSPFv3 packets. After IPsec is configured for
OSPFv3, IPsec operation is invisible to the user.
•
You can only enable one security protocol (AH or ESP) at a time on an interface or for an area. Enable IPsec AH with the
ipv6
ospf authentication
command; enable IPsec ESP with the
ipv6 ospf encryption
command.
• The security policy configured for an area is inherited by default on all interfaces in the area.
• The security policy configured on an interface overrides any area-level configured security for the area to which the interface is
assigned.
• The configured authentication or encryption policy is applied to all OSPFv3 packets transmitted on the interface or in the area. The
IPsec security associations (SAs) are the same on inbound and outbound traffic on an OSPFv3 interface.
• There is no maximum AH or ESP header length because the headers have fields with variable lengths.
• Manual key configuration is supported in an authentication or encryption policy (dynamic key configuration using the internet key
exchange [IKE] protocol is not supported).
• In an OSPFv3 authentication policy:
•
AH is used to authenticate OSPFv3 headers and certain fields in IPv6 headers and extension headers.
• MD5 and SHA1 authentication types are supported; encrypted and unencrypted keys are supported.
• In an OSPFv3 encryption policy:
•
Both encryption and authentication are used.
• IPsec security associations (SAs) are supported only in Transport mode (Tunnel mode is not supported).
• ESP with null encryption is supported for authenticating only OSPFv3 protocol headers.
• ESP with non-null encryption is supported for full confidentiality.
• 3DES, DES, AES-CBC, and NULL encryption algorithms are supported; encrypted and unencrypted keys are supported.
NOTE: To encrypt all keys on a router, use the
service password-encryption
command in Global Configuration mode.
However, this command does not provide a high level of network security. To enable key encryption in an IPsec security policy at
an interface or area level, specify
7
for
[key-encryption-type]
when you enter the
ipv6 ospf authentication
ipsec
or
ipv6 ospf encryption ipsec
command.
• To configure an IPsec security policy for authenticating or encrypting OSPFv3 packets on a physical, port-channel, or VLAN interface
or OSPFv3 area, perform any of the following tasks:
•
Configuring IPsec Authentication on an Interface
• Configuring IPsec Encryption on an Interface
• Configuring IPsec Authentication for an OSPFv3 Area
• Configuring IPsec Encryption for an OSPFv3 Area
• Displaying OSPFv3 IPsec Security Policies
Configuring IPsec Authentication on an Interface
To configure, remove, or display IPsec authentication on an interface, use the following commands.
Prerequisite : Before you enable IPsec authentication on an OSPFv3 interface, first enable IPv6 unicast routing globally, configure an IPv6
address and enable OSPFv3 on the interface, and assign it to an area (refer to Configuration Task List for OSPFv3 (OSPF for IPv6) ).
The SPI value must be unique to one IPsec security policy (authentication or encryption) on the router. Configure the same authentication
policy (the same SPI and key) on each OSPFv3 interface in a link.
570 Open Shortest Path First (OSPFv2 and OSPFv3)