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    6.0.0
    6.0.0

    GRE over IPsec (Cisco VPN)

    GRE over IPsec (Cisco VPN)

    This section describes how to configure a FortiGate VPN that is compatible with Cisco-style VPNs that use GRE in an IPsec tunnel.

    Cisco products that include VPN support often use Generic Routing Encapsulation (GRE) protocol tunnel over IPsec encryption. This chapter describes how to configure a FortiGate unit to work with this type of Cisco VPN.

    Cisco VPNs can use either transport mode or tunnel mode IPsec. Before FortiOS 4.0 MR2, the FortiGate unit was compatible only with tunnel mode IPsec.

    For information about configuring the FortiGate unit and Cisco router, see Configuration overview.

    Example FortiGate to Cisco GRE-over-IPsec VPN

    In this example, users on LAN1 are provided access to LAN2.

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    GRE over IPsec (Cisco VPN)

    GRE over IPsec (Cisco VPN)

    This section describes how to configure a FortiGate VPN that is compatible with Cisco-style VPNs that use GRE in an IPsec tunnel.

    Cisco products that include VPN support often use Generic Routing Encapsulation (GRE) protocol tunnel over IPsec encryption. This chapter describes how to configure a FortiGate unit to work with this type of Cisco VPN.

    Cisco VPNs can use either transport mode or tunnel mode IPsec. Before FortiOS 4.0 MR2, the FortiGate unit was compatible only with tunnel mode IPsec.

    For information about configuring the FortiGate unit and Cisco router, see Configuration overview.

    Example FortiGate to Cisco GRE-over-IPsec VPN

    In this example, users on LAN1 are provided access to LAN2.

    Previous
    Next