The L2F (Layer 2 Forwarding) tunneling protocol is supported by Nortel Networks and other vendors. L2F tunneling allows remote access to corporate networks across the public Internet. L2F tunnels are generally established between the network access server at the ISP and the gateway.
There is no direct client software required for L2F beyond the PPP dialer software, such as the dial-up networking utility provided with Windows 95 and Windows 98. L2F tunnels are actually made from the ISP to the corporate gateway on behalf of the user. These connections depend on the domain associated with the dial-in username. Therefore, ISPs must offer services that are based on L2F; currently, L2F is available on a limited basis. L2F provides IP address translation using encapsulation and support for IPX tunneling, but it does not perform encryption. L2F offers the following features: