Intel ER8100STUS - Express 8100 Router, Справочное руководство

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Reference.bok : Chapter02 13 Wed Apr 22 10:58:08 1998
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Point-to-Point Protocol (PPP)
Leased Lines Links
Use of passwords
For the correct operation of PPP links using CHAP, the passwords must be con-
figured as follows:
If Device 1 has Password A configured for CHAP requests on the PPP link, De-
vice 2 must reply to the request using Password A. That is, Password A must be
defined in Device 2 for CHAP replies to Device 1.
Similarly, if Device 2 has Password B configured for CHAP requests on the PPP
link, Device 1 must reply to the request using Password B. That is, Password B
must be defined in Device 1 for CHAP replies to Device 2.
Global (all PPP links)
and Local replies to
CHAP requests
A device always tries to reply to a request for authentication from a peer, using
the password defined for the User ID of the peer.
In the Intel Express 8100 Router, a list of passwords for User IDs can be defined
for both the router (global) and for individual PPP links. The passwords in the
global list can be used in reply to CHAP requests from peers on any of the PPP
links to the router. The passwords in the local list can only be used for peers on
the PPP link for which they are defined. The router first tries to find the User ID
of the peer requesting authentication in the local password list and then in the glo-
bal password list.
In some devices, a common User ID with different passwords are used for com-
munications over a PPP link. In these cases, local User IDs and password should
be defined. Otherwise, global User IDs and passwords can generally be used.
CHAP requests from the
router
When CHAP requests are enabled, the Intel Express 8100 Router authenticates
the peer over the PPP link whenever the link is established. For on-demand
(switched) PPP links including ISDN links, the router authenticates the peer
whenever the link is brought up.
Password A
used for
CHAP requests
Device 1 (User ID1)
Request
Request
Reply
Reply
Device 2 (User ID2)
Password A
used in reply
to CHAP requests
from User ID1
Password B
used for
CHAP requests
Password B
used in reply to
CHAP requests
from User ID2
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