Dell S4820T, Configuration Manual

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The following example shows the
show ipv6 ospf database grace-lsa
command.
Dell#show ipv6 ospf database grace-lsa
!
Type-11 Grace LSA (Area 0)
LS Age : 10
Link State ID : 6.16.192.66
Advertising Router : 100.1.1.1
LS Seq Number : 0x80000001
Checksum : 0x1DF1
Length : 36
Associated Interface : Te 5/3
Restart Interval : 180
Restart Reason : Switch to Redundant Processor
OSPFv3 Authentication Using IPsec
OSPFv3 uses IPsec to provide authentication for OSPFv3 packets. IPsec authentication ensures security in
the transmission of OSPFv3 packets between IPsec-enabled routers.
IPsec is a set of protocols developed by the internet engineering task force (IETF) to support secure
exchange of packets at the IP layer. IPsec supports two encryption modes: transport and tunnel.
• Transport mode — encrypts only the data portion (payload) of each packet, but leaves the header
untouched.
• Tunnel mode — is more secure and encrypts both the header and payload. On the receiving side, an
IPsec-compliant device decrypts each packet.
NOTE: Dell Networking OS supports only Transport Encryption mode in OSPFv3 authentication with
IPsec.
With IPsec-based authentication, Crypto images are used to include the IPsec secure socket application
programming interface (API) required for use with OSPFv3.
To ensure integrity, data origin authentication, detection and rejection of replays, and confidentiality of
the packet, RFC 4302 and RFC 4303 propose using two security protocols — authentication header (AH)
and encapsulating security payload (ESP). For OSPFv3, these two IPsec protocols provide interoperable,
high-quality cryptographically-based security.
• HA — IPsec authentication header is used in packet authentication to verify that data is not altered
during transmission and ensures that users are communicating with the intended individual or
organization. Insert the authentication header after the IP header with a value of 51. AH provides
integrity and validation of data origin by authenticating every OSPFv3 packet. For detailed information
about the IP AH protocol, refer to RFC 4302 .
• ESP — encapsulating security payload encapsulates data, enabling the protection of data that follows
in the datagram. ESP provides authentication and confidentiality of every packet. The ESP extension
header is designed to provide a combination of security services for both IPv4 and IPv6. Insert the ESP
header after the IP header and before the next layer protocol header in Transport mode. It is possible
to insert the ESP header between the next layer protocol header and encapsulated IP header in
Tunnel mode. However, Tunnel mode is not supported in Dell Networking OS. For detailed
information about the IP ESP protocol, refer to RFC 4303 .
In OSPFv3 communication, IPsec provides security services between a pair of communicating hosts or
security gateways using either AH or ESP. In an authentication policy on an interface or in an OSPF area,
AH and ESP are used alone; in an encryption policy, AH and ESP may be used together. The difference
Open Shortest Path First (OSPFv2 and OSPFv3)
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