Allied Telesis AR440S manual Background NAT-T and policies, Internet

Page 4

Background: NAT-T and policies

NAT-TNAT Traversal (NAT-T) can be enabled on any of our IPsec VPN links. It automatically allows IPsec VPNs to traverse any NAT gateways that may be in the VPN path. This is likely to occur with the VPNs from the roaming VPN clients—they are likely to use a LAN at a remote site that is behind a NAT gateway.

NAT-T may also be applicable for a site-to-site VPN, if one of the routers is behind a NAT gateway, such as some ADSL devices. Note that AR44xS series routers provide an ADSL interface, which removes the need for a separate ADSL device. Therefore, the examples in this How To Note do not include NAT-T for the site-to-site VPNs.

The following figure shows how the addresses in the IPsec headers change as a packet from a roaming client traverses NAT gateways in the VPN pathway. The figure illustrates IPsec transport mode with L2TP.

roaming VPN

client

192.168.200.1

192.168.200.254

Encrypted

NAT gateway

211.211.211.1

hotel

Encrypted

Internet

headquarters

200.200.200.1

VPN access

concentrator

192.168.140.254

192.168.140.27

 

 

hotel

 

 

 

 

Source Addr

Dest Addr

IP

192.168.143.1

192.168.140.27

PPP

N/A

N/A

L2TP

N/A

N/A

IPsec

N/A

N/A

IP

192.168.200.1

200.200.200.1

ETH

N/A

N/A

 

 

 

 

Source Addr

Dest Addr

IP

192.168.143.1

192.168.140.27

PPP

N/A

N/A

L2TP

N/A

N/A

IPsec

N/A

N/A

IP

211.211.211.1

200.200.200.1

ETH

N/A

N/A

 

 

 

headquarters

 

Source Addr

Dest Addr

IP

192.168.143.1

192.168.140.27

 

 

 

ETH

N/A

N/A

 

 

 

vpn-nat-t.eps

Page 4 AlliedWare™ OS How To Note: VPNs for Corporate Networks

Image 4
Contents Contents IntroductionRelated How To Notes About IPsec modes tunnel and transport L2TPBackground NAT-T and policies Internet5 AlliedWare OS How To Note VPNs for Corporate Networks How to configure VPNs in typical corporate networks VlanBefore you start ATM DslamHow to configure the headquarters VPN access concentrator Configure general system and user settingsConfigure IP for internet access Configure remote management access, if desiredConfigure dynamic PPP over L2TP connections Capture status information remotely, if desiredCheck feature licences Enable Isakmp Configure the firewall’s basic settings Configure the firewall’s access rules Save your configuration How to configure the AR440S router at branch office Configure PPP for PPPoA Configure Adsl for internet accessConfigure IP 18 AlliedWare OS How To Note VPNs for Corporate Networks Create ip pool=roaming ip=192.168.144.1-192.168.144.50 Create ipsec pol=internet int=ppp0 ac=permit Add firewall policy=branch1 int=vlan1 type=private 22 AlliedWare OS How To Note VPNs for Corporate Networks 23 AlliedWare OS How To Note VPNs for Corporate Networks Set system name=Branch2 Configure PPP for PPPoE 26 AlliedWare OS How To Note VPNs for Corporate Networks Configure the VPNs for connecting to the headquarters office Enable isakmp 29 AlliedWare OS How To Note VPNs for Corporate Networks How to make voice traffic high priority Create classifiers Reduce the MTUFor site-to-site VPNs, apply the SQoS policy to the tunnels For roaming clients, set L2TP TOS reflectionSet int=ppp0 mtu=256 34 AlliedWare OS How To Note VPNs for Corporate Networks Apply the SQoS policy to the tunnel How to test your VPN solution LANs areConfiguration scripts for headquarters and branch offices Before you use these scriptsHeadquarters VPN access concentrators configuration # Dhcp configuration # SSH configuration# Log configuration # Ipsec configuration# Isakmp Configuration # Firewall configuration # INT configuration if prioritising VoIP # Classifier configuration if prioritising VoIP# Software QoS configuration if prioritising VoIP # Trigger configuration if prioritising VoIP# Adsl configuration # ATM configuration# PPP configuration for PPPoA 44 AlliedWare OS How To Note VPNs for Corporate Networks 45 AlliedWare OS How To Note VPNs for Corporate Networks 46 AlliedWare OS How To Note VPNs for Corporate Networks Set int=ppp0 mtu=256 Set int=ppp0 frag=yes # ETH configuration # PPP configuration for PPPoE49 AlliedWare OS How To Note VPNs for Corporate Networks 50 AlliedWare OS How To Note VPNs for Corporate Networks 51 AlliedWare OS How To Note VPNs for Corporate Networks # PPP templates configuration ISPs PPPoE access concentrator configuration# PPP configuration Hotels NAT gateway firewall configuration # Firewall configuration enable firewall
Related manuals
Manual 54 pages 52.17 Kb

AR440S specifications

Allied Telesis offers a range of advanced routers designed to meet the connectivity and operational needs of modern enterprises. Among its extensive lineup, the AR450S, AR441S, AR415S, AR442S, and AR440S models stand out for their robust features and technologies, making them ideal solutions for various networking environments.

The Allied Telesis AR450S is a high-performance router tailored for service providers and large enterprises. It supports advanced routing protocols, including IPv4 and IPv6, ensuring compatibility with both legacy and modern networks. The AR450S boasts substantial throughput capabilities, making it suitable for bandwidth-intensive applications. Its versatile WAN options, including Ethernet and cellular connectivity, allow seamless integration into diverse network architectures.

Next in the lineup is the AR441S, which focuses on providing enhanced security and reliability. With built-in firewall capabilities and VPN support, this model ensures secure communication over the internet. The AR441S also features numerous Ethernet ports for flexible connectivity, enabling organizations to scale their networks as needed. Its user-friendly interface facilitates straightforward configuration and management.

The AR415S is designed for branch offices and small to medium-sized enterprises. This router offers a balance of performance and affordability, equipped with essential features like Quality of Service (QoS) and traffic shaping. The AR415S supports multiple WAN connections, which helps in maintaining reliable internet access by auto-failing to backup connections when necessary.

The AR442S incorporates advanced networking technologies, including dynamic routing protocols and deep packet inspection. This model enhances performance by optimizing traffic flow and improving bandwidth utilization. Its support for VoIP and other multimedia applications makes it an excellent choice for organizations seeking to maximize their communication capabilities.

Lastly, the AR440S is engineered for high availability and redundancy. It includes dual power supplies and hot-swappable components, ensuring that network services remain uninterrupted during maintenance. The AR440S is particularly valuable in mission-critical environments where downtime can lead to significant business disruption.

In summary, the Allied Telesis AR series routers—AR450S, AR441S, AR415S, AR442S, and AR440S—offer a rich set of features tailored to various operational needs. With their advanced routing capabilities, security features, and reliable performance, these routers represent the cutting edge of networking technology for businesses looking to enhance their connectivity and operational efficiency.