Configuring L2TP Services

6.In the L2TP Tunneling Security window, enable tunnel authentication.

Parameter Name

Value

 

 

Enable Tunnel Authentication

Enable

 

 

Tunnel Authentication Password

LAC1

 

 

7.In the L2TP IP Interface window, enter the L2TP IP address.

Parameter Name

Value

 

 

L2TP IP Interface Address

192.32.68.2

 

 

Subnet Mask

255.255.255.0

 

 

During the L2TP session, the RADIUS server assigns the following IP addresses:

jsmart@baynetworks.com: 192.32.40.1

mmark@baynetworks.com: 192.32.40.2

These addresses are stored in the RADIUS server database.

Data Path Through the Network

After all components of the network are configured, jsmart can place a call to the local ISP. The LAC that receives this call sends the user name to the TMS, which verifies the domain name and address and sends this information back to the LAC so that it can forward the data.

The LAC then negotiates the initiation of the tunnel with the LNS, and the tunnel is brought up. The LNS then authenticates jsmart@baynetworks.com with the RADIUS server. After the RADIUS server grants access, it assigns the address

192.32.40.1to jsmart, to include the remote host (jsmart’s PC) in the virtual private network.

Data now passes through the tunnel from jsmart’s PC to the LNS for the duration of the L2TP session. When jsmart disconnects the call, the session is terminated. If no other active sessions are using the tunnel, the tunnel is brought down.

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Nortel Networks manual Data Path Through the Network, L2TP IP Interface window, enter the L2TP IP address

L2TP specifications

Nortel Networks L2TP, or Layer 2 Tunneling Protocol, is a widely recognized networking protocol that enables the tunneling of data over various networks. Initially developed as an extension of the Point-to-Point Tunneling Protocol (PPTP), L2TP integrates components from both PPTP and Layer 2 Forwarding (L2F). Nortel Networks played a significant role in the development and implementation of L2TP, making it a prominent choice for service providers and enterprise networks seeking secure and efficient connectivity.

One of the primary features of L2TP is its ability to encapsulate data packets, allowing the transport of PPP (Point-to-Point Protocol) frames without necessitating the traditional point-to-point connections. This means L2TP can operate across different networks, facilitating remote access connections and VPNs (Virtual Private Networks). As a result, organizations can achieve greater flexibility in managing their communications infrastructure.

Another key characteristic of L2TP is its support for both IPv4 and IPv6, ensuring compatibility with current and future networking environments. L2TP operates at the link layer of the OSI model, which means it functions between the data link and network layers, making it versatile for various applications. By using UDP (User Datagram Protocol) as a transport protocol, L2TP ensures efficient data transmission while maintaining lower latencies.

Security is a critical aspect of L2TP. While L2TP itself does not provide encryption, it is often paired with IPSec (Internet Protocol Security) for enhanced security protocols. This combination offers both tunneling and encryption, creating a secure framework for transmitting sensitive information across potentially insecure networks, such as the Internet.

L2TP also features various authentication methods, allowing for robust access control. It supports various schemes like PAP (Password Authentication Protocol) and CHAP (Challenge Handshake Authentication Protocol), giving network administrators a range of options to ensure the legitimacy of users accessing the network.

In summary, Nortel Networks L2TP is a powerful tunneling protocol known for its flexibility, compatibility, and security features. Its ability to encapsulate data for efficient transport makes it ideal for remote access and VPN applications. As organizations continue to demand secure, seamless connectivity, L2TP remains a resilient choice within the shifting landscape of networking technologies.