4-5
VPN Acceleration Module 2+ (VAM2+) Installation and Configuration Guide
OL-5979-03
Chapter 4 Configuring the SA-VAM2+
Configuration Tasks
Defining a Transform Set
A transform set is a combination of security protocols and algorithms. During the IPSec security
association negotiation, peers agree to use a specific transform set to protect a particular data flow.
To define a transform set, use the following commands, starting in global configuration mode:
Table 4-1
shows allowed transform combinations for the AH and ESP protocols.
Command
Purpose
Step 1
Router(config)#
crypto ipsec
transform-set
transform-set-name
transform1
[
transform2
[
transform3
]]
Defines a transform set and enters crypto transform configuration
mode.
•
transform-set-name
—Specifies the name of the transform set
to create (or modify).
•
transform1
[
transform2
[
transform3
]
[
transform4
]]—Defines the IPSec security protocols and
algorithms. Accepted transform values are described in
Table 4-1
.
Step 2
Router(cfg-crypto-tran)#
mode
[
tunnel
|
transport
]
(Optional) Changes the mode associated with the transform set.
The mode setting is only applicable to traffic whose source and
destination addresses are the IPSec peer addresses; it is ignored
for all other traffic. (All other traffic is in tunnel mode only.)
Step 3
end
Exits the crypto transform configuration mode to enabled mode.
Step 4
clear crypto sa
or
clear crypto sa peer
{
ip-address
|
peer-name
}
or
clear crypto sa map
map-name
or
clear crypto sa spi
destination-address
protocol spi
Clears existing IPSec security associations so that any changes to
a transform set take effect on subsequently established security
associations (SAs). (Manually established SAs are reestablished
immediately.)
Using the
clear crypto sa
command without parameters clears
out the full SA database, which clears out active security sessions.
You may also specify the
peer
,
map
, or
entry
keywords to clear
out only a subset of the SA database.
Table 4-1
Allowed Transform Combinations
Transform type
Transform
Description
AH Transform
(Pick up to one.)
ah-md5-hmac
ah-sha-hmac
AH with the MD5 (Message Digest 5)
(HMAC variant) authentication algorithm
AH with the SHA (Secure Hash Algorithm)
(HMAC variant) authentication algorithm