Configuring group L2TP settings

1. To change group level L2TP settings, select ProfilesGroups, then click Edit for the associated group that you want to configure. The Edit Group screen appears.
2. Click Configure in the L2TP section of the screen. The GroupsEditL2TP screen appears.

Figure 11 ProfilesGroupsEditL2TP screen



3. Click the Configure button for a specific parameter to make changes to that parameter. Click Configure in the All Fields section to edit all parameters at the same time. Use the Inherited button to set all fields to their inherited values.
4. Select one or more of the L2TP Authentication methods.
5. Configure the compression setting. Click to enable the L2TP Microsoft Point-to-Point Compression (MPPC ) packet compression. Compression should be used when encryption is selected on analog modems. This is because encryption renders a modem's compression ineffective, and it can severely affect the performance of compressible applications. Also, data that is compressed before being transmitted makes more efficient use of lower speed network links.
   
   You should use data compression in most situations. Users with cable modems or xDSL connections to the ISP , or locally on the LAN, would find it is probably unnecessary to compress packets. This is because the speed of the link, relative to the rate of compression and the benefit of compressing before encrypting, might be negligible or might not increase performance.
   
   Also, some data cannot be compressed; for example, a previously compressed file does not lend itself well to additional compression.
6. Set the Use Client-Specified Address parameter. Click to enable use of a Client-Specified Address . This option allows the gateway to accept the IP address from a remote user's system during tunnel setup. This option is Disabled by default.
   
   When enabled and the client provides an IP address, this is the IP address that is used by the client for the duration of the tunneled session (it becomes the first or default choice).
7. Enter the Primary DNS. Enter the address of the Primary Domain Name System (DNS) server that is located on your private network. This DNS address is provided by the server to tunnel clients at setup and is used through the tunnel. The DNS server translates textual host names into IP addresses for the gateway. For example, DNS can translate the fully qualified host www.mycompany.com to its IP address 192.19.2.33.
   
   The Primary DNS server is the first one addressed for servicing name resolution requests from a remote user; if the Primary DNS server is unavailable, service is requested of the Secondary DNS server. Recent versions of Microsoft Windows operating systems can simultaneously query multiple DNS servers.
   
   Always use the IP address for setting a DNS server host instead of a domain name.
8. Enter the Secondary DNS. Enter an address for the Secondary Domain Name System (DNS) server. If the Primary DNS server is unavailable, service is requested of the Secondary DNS server.
9. Enter the Primary WINS. Enter an address for the primary Windows Internet Naming Service (WINS ) server. A WINS server resolves NetBIOS names (for Windows networking file and print services) to IP addresses. Using a WINS server enables normal Windows file and print services to be accessed correctly through a tunnel connection.
   
   Windows NT Server Version 4.0 and later supports a built-in WINS server. The WINS server eliminates the need to manually map NetBIOS names to IP addresses (for example, using the textual LMHOSTS file on Windows) by updating a name-to-address mapping file dynamically on the WINS server.
   
   The Primary WINS server is the first one addressed for servicing name resolution requests from a remote user; if the Primary WINS server is unavailable, service is requested of the Secondary WINS server. Always use the IP address for setting a WINS server host instead of a name.
   
   

   Note: If no WINS servers are specified, the client is forced to broadcast for NetBIOS names.

   
   
10. Enter an address for the Secondary Windows Internet Naming Service (WINS) server; if the Primary WINS server is unavailable, service is requested of the Secondary WINS server.