Fortinet FortiGate 1000A, Руководство администратора

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Manual key VPN
Manual key
If required, you can manually define cryptographic keys for establishing an IPSec VPN
tunnel. You would define manual keys in situations where:
• Prior knowledge of the encryption and/or authentication key is required (that is,
one of the VPN peers requires a specific IPSec encryption and/or authentication
key).
• Encryption and authentication needs to be disabled.
In both cases, you do not specify IPSec phase 1 and phase 2 parameters; you define
manual keys on the
VPN > IPSEC > Manual Key tab instead.
If one of the VPN peers uses specific authentication and encryption keys to establish
a tunnel, both VPN peers must be configured to use the same encryption and
authentication algorithms and keys.
It is essential that both VPN peers be configured with matching encryption and
authentication algorithms, matching authentication and encryption keys, and
complementary Security Parameter Index (SPI) settings.
Each SPI identifies a Security Association (SA). The value is placed in ESP
datagrams to link the datagrams to the SA. When an ESP datagram is received, the
recipient refers to the SPI to determine which SA applies to the datagram. An SPI
must be specified manually for each SA. Because an SA applies to communication in
one direction only, you must specify two SPIs per configuration (a local SPI and a
remote SPI) to cover bidirectional communications between two VPN peers.
To specify manual keys for creating a tunnel
1 Go to VPN > IPSEC > Manual Key and select Create New.
Internet
browsing Select the FortiGate interface to the local private network if the FortiGate unit
has to support an Internet-browsing configuration. Do not select this option on
FortiGate units that act as dialup clients.
Quick Mode
Identities Enter the method for choosing selectors for IKE negotiations:
• To choose a selector from a firewall encryption policy, select Use selectors
from policy.
• To disable selector negotiation, select Use wildcard selectors.
• To specify the firewall encryption policy source and destination IP
addresses, select Specify a selector and then select the names of the
source and destination addresses from the Source address and Dest
address lists. You may optionally specify source and destination port
numbers and/or a protocol number.
Note: It may not be safe or practical to define manual keys because network administrators
must be trusted to keep the keys confidential, and propagating changes to remote VPN peers in
a secure manner may be difficult.
!
Caution: If you are not familiar with the security policies, SAs, selectors, and SA databases for
your particular installation, do not attempt the following procedure without qualified assistance.