LCS60 Configuration and Connection for PPP Service

PPP

Reserved IP Address

The user requests a reserved IP address by omitting the -Doption on his/her data switch dialstring and by having a negotiable IP address administered in his/her client software package. The reserved IP address must be centrally administered by the LCS60 administrator prior to the user's call. To find that user's reserved IP address, the LCS60 searches its configuration database with both the IP network security group name and the user ID field. The latter value is extracted from the -uoption appended to the data switch dialstring by the NAC. In the absence of a NAC or an explicit -uoption, the user ID defaults to the value guest. If the LCS60 does not find a reserved IP address for the given combination of the IP network and user ID, then the session start up request is assigned a dynamic IP address.

If the reserved IP address is allocated when a second session setup attempt is made for the same user ID, the call is refused and an entry is placed in the ppp.log file. A given user ID can have multiple reserved IP addresses, one for each of the IP network security groups that has been configured on the LCS60.

Note: Reserved IP addresses can only be allocated by the system administrator or someone with root permissions.

To reserve specific addresses for users:

Use the ipas command (Screen 4-2)

Select option 2 to display the RESERVED IP ADDRESSES FOR SLIP AND PPP SERVICES menu

Select option 1 from this menu.

This will prompt for the login ID, group, and address as shown in Screen 4-2. If you are using a NAC, the User Login Id is the NAC ID, otherwise, enter your own unique login ID. In the example in Screen 4-2, user tbaker is assigned the address 154.12.23.7 in the group morse.

To request the reserved IP address allocated for your PC or Mac by the LCS60 administrator, enter zero for the client package's IP address and omit the -Doption from the data switch dialstring. The PPP software will then receive this address during IP negotiation with the LCS60 PPP server.

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Issue 3