Q. I’m using Fedora Core Linux. Recently I changed my ISP. Now I get error as follows when I try to start PPP:
PPP authorization failed
Machine not authorized to use this PPP address
How do I fix this problem?
A. PPP is the protocol used for establishing internet links over dial-up modems, DSL connections, and many other types of point-to-point links. The pppd daemon works together with the kernel PPP driver to establish and maintain a PPP link with another system (called the peer) and to negotiate Internet Protocol (IP) addresses for each end of the link. Pppd can also authenticate the peer and/or supply authentication information to the peer. PPP can be used with other network protocols besides IP, but such use is becoming increasingly rare.
Auth option require the peer to authenticate itself before allowing network packets to be sent or received. This option is the default if the system has a default route.
By adding noauth option you can get rid of this problem. It means ppp do not require the peer to authenticate itself. Open /etc/ppp/options file:
# vi /etc/ppp/options
Save and close the file. Now run ppp and you should able to connect.