The Juniper SRX Services Gateway VPN must terminate all network connections associated with a communications session at the end of the session.

Idle TCP sessions can be susceptible to unauthorized access and hijacking attacks. IKE Dead Peer Detection (DPD) is a protocol that verifies the availability of IPsec peer devices by sending encrypted IKE Phase 1 notification payloads to peers.

Note: For dynamic (remote access) VPN, the TCP keep-alive for remote access is implemented in the Juniper SRX Firewall STIG.

Navigate to the IKE configuration.

[edit] show security ike gateway <ike-peer-name>

If the DPD options are not configured, this is a finding.

For site-to-site VPN, configure an Internet Key Exchange (IKE) gateway that includes DPD parameters such as in the following example.

set security ike gateway IKE-PEER ike-policy IKE-POLICY set security ike gateway IKE-PEER address <Peer IP Address> set security ike gateway IKE-PEER dead-peer-detection always-send set security ike gateway IKE-PEER dead-peer-detection interval 10 set security ike gateway IKE-PEER dead-peer-detection threshold 2 set security ike gateway IKE-PEER local-identity inet <IPv4 Address in Certificate> set security ike gateway IKE-PEER remote-identity inet <IPv4 Address in Remote Certificate> set security ike gateway IKE-PEER external-interface <interface name> set security ike gateway IKE-PEER version v2-only