ADTRAN Express L768 Owner's Manual page 121

Appendix B. Log Messages
IPXCP <X> up
level 5
IPX Control Protocol port <X> has been successfully negotiated be-
tween Express L768 and PPP peer.
LCP <X> down
level 5
Link Control Protocol port <X> has been dropped between Express
L768 and PPP peer.
LCP <X> up
level 5
Link Control Protocol port <X> has been successfully negotiated be-
tween Express L768 and PPP peer.
Link is looped back
level 3
The Express L768 has dialed a location which is looping back all data.
Essentially, it has negotiated PPP with itself.
Negot not converging
level 2
Negotiation of the LCP layer is unattainable due to misconfiguration
or the Express L768 or PPP peer is requiring authentication and the
other is refusing.
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