Before R80.10, Check Point "Maintrain" Security Gateways did not support initiating IKE propositions over NAT-T. A Security Gateway will accept and support proposals for industry UDP encapsulation behind port 4500, but will never initiate a proposal, unlike 600, 1100, 1200R and VPN-1 Edge Appliances that do support initiating IKE propositions

Network address translator traversal (NAT-T, česky průchod skrze NAT) je v počítačových sítích způsob navázání a správy spojení pomocí IP protokolu přes síťové prvky, které provádějí NAT (překlad síťových adres).Za standardních okolností totiž není možné navázat spojení s počítačem, který je umístěn za dynamickým NAT (tzv. „maškaráda“). Client Settings - Shrew The Firewall Options settings are used to define what features will be enabled to prevent problems from occurring when a Firewall or NAT router exists between the Client and a Gateway. NAT Traversal Mode. Set this value to Enable or Force if you want the VPN Client IPSEC Daemon to use the IKE and ESP NAT Traversal protocol extensions. Site to Site VPN R80.10 - Check Point Software For IPsec to work with NAT traversal, these protocols must be allowed through the NAT interface(s): IKE - UDP port 500; IPsec NAT-T - UDP port 4500; Encapsulating Security Payload (ESP) - IP protocol number 50; Authentication Header (AH) - IP protocol number 51; Configuring NAT-Traversal. To configure NAT-T for site-to-site VPN:

Configure IPSec VPN Phase 1 Settings NAT Traversal, or UDP Encapsulation, enables traffic to get to the correct destinations. In the Keep-alive Interval text box, type or select the number of seconds that pass before the next NAT keep-alive message is sent. To have the Firebox send messages to the IKE peer to keep the VPN tunnel open, select the IKE Keep-alive check box. How To Establish a Dial Out IPSec VPN from a Draytek Vigor

Jan 25, 2018 · IKE Phase 2 Negotiation NAT Traversal Decision. While IKE phase 1 detects NAT support and NAT existence along the network path, IKE phase 2 decides whether or not the peers at both ends will use NAT traversal. Quick Mode (QM) security association (SA) payload in QM1 and QM2 is used to for NAT traversal negotiation.

By default nat-traversal (NAT-T) is enabled for IKE gateways. The default NAT-T keepalive is 5 seconds. Therefore unless explicitly showing that NAT-T was disabled in the configuration, then the IKE phase 1 will attempt to use NAT-T if a NAT device is detected in the path between two peers. NAT-Traversal: Result using draft-ietf-ipsec-nat-t-ike-02 Is the Microsoft LT2P VPN (MSL2TP) NAT-Traversal supposed to work with FreeS/WAN? The default behaviour we experienced with NAT-T 0.5a + X.509 ended with: NAT-Traversal: Result using draft-ietf-ipsec-nat-t-ike-02/03: peer is NATed protocol/port in Phase 1 … IKE Gateway Advanced Options Tab Click to have UDP encapsulation used on IKE and UDP protocols, enabling them to pass through intermediate NAT devices. Enable NAT Traversal if Network Address Translation (NAT) is configured on a device between the IPSec VPN terminating points.