While IPsec VPN tunnels are hardcoded and essentially "nailed up" between two locations, DMVPN builds tunnels between locations as needed. It does this using typical routers with no additional feature capability, as is the case with SD-WAN. DMVPN tunnels are designed as a mesh network, as opposed to hub and spoke. That means DMVPN can take a

IPsec can protect data flows between a pair of hosts (host-to-host), between a pair of security gateways (network-to-network), or between a security gateway and a host (network-to-host). IPsec uses cryptographic security services to protect communications over Internet Protocol (IP) networks. It supports network-level peer authentication, data Apr 17, 2018 · The CloudGen Firewall can establish IPsec VPN tunnels to any standard compliant third-party IKEv1 IPsec VPN gateway. The site-to-site IPsec VPN tunnel must be configured with identical settings on both the CloudGen Firewall and the third-party IPsec gateway. For more information, see How to Create a site-to-site IPsec VPN Tunnel. The following diagram shows the two tunnels of the Site-to-Site VPN connection. When you create a Site-to-Site VPN connection, you download a configuration file specific to your customer gateway device that contains information for configuring the device, including information for configuring each tunnel. Site-to-Site IPSec VPN Tunnels are used to allow the secure transmission of data, voice and video between two sites (e.g offices or branches). The VPN tunnel is created over the Internet public network and encrypted using a number of advanced encryption algorithms to provide confidentiality of the data transmitted between the two sites. The importance of using tunnels in a VPN environment is based on the fact that IPSec encryption only works on IP unicast frames. Tunneling allows for the encryption and the transportation of multiprotocol traffic across the VPN since the tunneled packets appear to the IP network as an IP unicast frame between the tunnel endpoints. Once past authentication, an IPsec VPN relies on protections in the destination network, including firewalls and applications for access control, rather than in the VPN itself. IPsec standards do

In your case the above output would mean that L2L VPN type connection has been formed 3 times since the last reboot or clearing of these statistics. All the formings could be from this same L2L VPN connection. EDIT: And yes, there is only 1 Active VPN connection when you issued that command on your firewall. - Jouni

When configuring a IPSec VPN tunnel, it is recommended to enable PFS, or Perfect Forward Secrecy if both side of the VPN devices support the technology. It provides a more secure VPN tunnel. What is IPSec VPN PFS Perfect Forward Secrecy? To understand how PFS works, let’s quickly recap how IPSec tunnel works. Basic IPSec VPN

In your case the above output would mean that L2L VPN type connection has been formed 3 times since the last reboot or clearing of these statistics. All the formings could be from this same L2L VPN connection. EDIT: And yes, there is only 1 Active VPN connection when you issued that command on your firewall. - Jouni

VPN gateway "A" encrypts the private IP packet and relays it over an ESP tunnel to a peer VPN gateway at the edge of network "B." VPN gateway "B" then decrypts the packet and delivers it to the destination host. Like GRE, it doesn't really matter how the two VPN gateways communicate with each other -- hops in between just pass along the ESP packet. Apr 28, 2015 · Problems establishing a VPN connection. If the problem occurs during phase 1, see steps for troubleshooting IKE-related failures. If the problem occurs during phase 2, see steps for troubleshooting IPsec-related failures. Problems maintaining a VPN connection. If you successfully establish both VPN tunnels but still experience connectivity