R3166-R3206-HP High-End Firewalls VPN Configuration Guide-6PW101

14. The RADIUS server authenticates the access request and returns a response if the user passes

authentication.

15. The LNS assigns an internal IP address to the remote user. The user can now access the internal

resources of the enterprise network.

L2TP features

1. Flexible identity authentication mechanism and high security

L2TP itself does not provide security for connections. However, it has all the security features of PPP for it

allows for PPP authentication (CHAP or PAP). L2TP can also cooperate with IPsec to guarantee data

security, making tunneled data more resistant to attacks. In addition, tunnel encryption, end-to-end data

encryption, and end-to-end application-layer data encryption technologies can be used together with

L2TP for higher data security as required.

2. Multi-protocol transmission

L2TP tunnels PPP frames, which can be used to encapsulate packets of multiple network layer protocols.

3. RADIUS authentication

An LAC can send the username and password of a remote user to a RADIUS server for authentication.

4. Private address allocation

An LNS can reside behind the firewall of a corporate network, dynamically allocating private addresses

to remote users and managing the corporate private addresses (RFC 1918). This facilitates address

management and improves security.

5. Accounting flexibility

Accounting can be carried out on the LAC and LNS simultaneously, allowing bills to be generated on the

ISP side and charging and auditing to take place on the enterprise gateway. L2TP can provide such

accounting data as statistics on inbound and outbound traffic (in packets and bytes) and connection start

time and end time. All these enable flexible accounting.

6. Reliability

L2TP supports LNS backup. When the connection to the primary LNS is torn down, an LAC can establish

a new one to a secondary LNS. This redundancy enhances the reliability and fault tolerance of VPN

services.

Protocols and standards

• RFC 1661, The Point-to-Point Protocol (PPP)

• RFC 1918, Address Allocation for Private Internets

• RFC 2661, Layer Two Tunneling Protocol "L2TP"

Configuring L2TP in the web interface

NOTE:

You can perform only the LNS configuration in through web.