+The remote name is set as follows:
+.TP 3
+if the \fBremotename\fR option is given,
+then use the argument of the last \fBremotename\fR option seen
+.TP 3
+else if the remote IP address is specified with a hostname,
+then use that host name
+.TP 3
+else the remote name is the null string "".
+.LP
+Secrets are selected from the PAP secrets file as follows:
+.TP 2
+*
+For authenticating the peer, look for a secret with client ==
+username specified in the PAP authenticate-request, and server ==
+local name.
+.TP 2
+*
+For authenticating ourselves to the peer, look for a secret with
+client == our username, server == remote name.
+.LP
+When authenticating the peer with PAP, a secret of "" matches any
+password supplied by the peer. If the password doesn't match the
+secret, the password is encrypted using crypt() and checked against
+the secret again; thus secrets for authenticating the peer can be
+stored in encrypted form. If the \fBlogin\fR option was specified, the
+username and password are also checked against the system password
+database. Thus, the system administrator can set up the pap-secrets
+file to allow PPP access only to certain users, and to restrict the
+set of IP addresses that each user can use.
+.LP
+Secrets are selected from the CHAP secrets file as follows:
+.TP 2
+*
+For authenticating the peer, look for a secret with client == name
+specified in the CHAP-Response message, and server == local name.
+.TP 2
+*
+For authenticating ourselves to the peer, look for a secret with
+client == local name, and server == name specified in the
+CHAP-Challenge message.
+.LP
+Authentication must be satisfactorily completed before IPCP (or any
+other Network Control Protocol) can be started. If authentication
+fails, \fIpppd\fR will terminated the link (by closing LCP). If IPCP
+negotiates an unacceptable IP address for the remote host, IPCP will
+be closed. IP packets can only be sent or received when IPCP is open.
+.SH ROUTING
+.LP
+When IPCP negotiation is completed successfully,
+.I pppd
+will inform the kernel of the local and remote IP addresses for the
+ppp interface. This is sufficient to create a
+host route to the remote end of the link, which will enable the peers
+to exchange IP packets. Communication with other machines generally
+requires further modification to routing tables and/or ARP (Address
+Resolution Protocol) tables. In some cases this will be done
+automatically through the actions of the \fIrouted\fR or \fIgated\fR
+daemons, but in most cases some further intervention is required.
+.LP
+Sometimes it is desirable
+to add a default route through the remote host, as in the case of a
+machine whose only connection to the Internet is through the ppp
+interface. The \fBdefaultroute\fR option causes \fIpppd\fR to create such a
+default route when IPCP comes up, and delete it when the link is
+terminated.
+.LP
+In some cases it is desirable to use proxy ARP, for example on a
+server machine connected to a LAN, in order to allow other hosts to
+communicate with the remote host. The \fBproxyarp\fR option causes \fIpppd\fR
+to look for a network interface on the same subnet as the remote host
+(an interface supporting broadcast and ARP, which is up and not a
+point-to-point or loopback interface). If found, \fIpppd\fR creates a
+permanent, published ARP entry with the IP address of the remote host
+and the hardware address of the network interface found.
+.SH EXAMPLES
+.LP
+In the simplest case, you can connect the serial ports of two machines
+and issue a command like
+.IP
+pppd /dev/ttya 9600 passive
+.LP
+to each machine, assuming there is no \fIgetty\fR running on the
+serial ports. If one machine has a \fIgetty\fR running, you can use
+\fIkermit\fR or \fItip\fR on the other machine to log in to the first
+machine and issue a command like
+.IP
+pppd passive
+.LP
+Then exit from the communications program (making sure the connection
+isn't dropped), and issue a command like
+.IP
+pppd /dev/ttya 9600
+.LP
+The process of logging in to the other machine and starting \fIpppd\fR
+can be automated by using the \fBconnect\fR option to run \fIchat\fR,
+for example:
+.IP
+pppd /dev/ttya 38400 connect 'chat "" "" "login:" "username"
+"Password:" "password" "% " "exec pppd passive"'
+.LP
+If your serial connection is any more complicated than a piece of
+wire, you may need to arrange for some control characters to be
+escaped. In particular, it is often useful to escape XON (^Q) and
+XOFF (^S), using \fBasyncmap a0000\fR. If the path includes a telnet,
+you probably should escape ^] as well (\fBasyncmap 200a0000\fR).
+Don't use an rlogin in the path - many implementations are not
+transparent; they will remove the sequence [0xff, 0xff, 0x73, 0x73,
+followed by any 8 bytes] from the stream.
+.SH DIAGNOSTICS
+.LP
+Messages are sent to the syslog daemon using facility
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