+.B require\-mppe\-40
+Require the use of MPPE, with 40-bit encryption.
+.TP
+.B require\-mppe\-128
+Require the use of MPPE, with 128-bit encryption.
+.TP
+.B require\-mschap
+Require the peer to authenticate itself using MS\-CHAP [Microsoft Challenge
+Handshake Authentication Protocol] authentication.
+.TP
+.B require\-mschap\-v2
+Require the peer to authenticate itself using MS\-CHAPv2 [Microsoft Challenge
+Handshake Authentication Protocol, Version 2] authentication.
+.TP
+.B require\-eap
+Require the peer to authenticate itself using EAP [Extensible
+Authentication Protocol] authentication.
+.TP
+.B require\-pap
+Require the peer to authenticate itself using PAP [Password
+Authentication Protocol] authentication.
+.TP
+.B set \fIname\fR=\fIvalue
+Set an environment variable for scripts that are invoked by pppd.
+When set by a privileged source, the variable specified by \fIname\fR
+cannot be changed by options contained in an unprivileged source. See
+also the \fIunset\fR option and the environment described in
+\fISCRIPTS\fR.
+.TP
+.B show\-password
+When logging the contents of PAP packets, this option causes pppd to
+show the password string in the log message.
+.TP
+.B silent
+With this option, pppd will not transmit LCP packets to initiate a
+connection until a valid LCP packet is received from the peer (as for
+the `passive' option with ancient versions of pppd).
+.TP
+.B srp\-interval \fIn
+If this parameter is given and pppd uses EAP SRP\-SHA1 to authenticate
+the peer (i.e., is the server), then pppd will use the optional
+lightweight SRP rechallenge mechanism at intervals of \fIn\fR
+seconds. This option is faster than \fBeap\-interval\fR
+reauthentication because it uses a hash\-based mechanism and does not
+derive a new session key.
+.TP
+.B srp\-pn\-secret \fIstring
+Set the long-term pseudonym-generating secret for the server. This
+value is optional and if set, needs to be known at the server
+(authenticator) side only, and should be different for each server (or
+poll of identical servers). It is used along with the current date to
+generate a key to encrypt and decrypt the client's identity contained
+in the pseudonym.
+.TP
+.B srp\-use\-pseudonym
+When operating as an EAP SRP\-SHA1 client, attempt to use the pseudonym
+stored in ~/.ppp_pseudonym first as the identity, and save in this
+file any pseudonym offered by the peer during authentication.
+.TP
+.B sync
+Use synchronous HDLC serial encoding instead of asynchronous.
+The device used by pppd with this option must have sync support.
+Currently supports Microgate SyncLink adapters
+under Linux and FreeBSD 2.2.8 and later.
+.TP
+.B unit \fInum
+Sets the ppp unit number (for a ppp0 or ppp1 etc interface name) for outbound
+connections. If the unit is already in use a dynamically allocated number will
+be used.
+.TP
+.B ifname \fIstring
+Set the ppp interface name for outbound connections. If the interface name is
+already in use, or if the name cannot be used for any other reason, pppd will
+terminate.
+.TP
+.B unset \fIname
+Remove a variable from the environment variable for scripts that are
+invoked by pppd. When specified by a privileged source, the variable
+\fIname\fR cannot be set by options contained in an unprivileged
+source. See also the \fIset\fR option and the environment described
+in \fISCRIPTS\fR.
+.TP
+.B updetach
+With this option, pppd will detach from its controlling terminal once
+it has successfully established the ppp connection (to the point where
+the first network control protocol, usually the IP control protocol,
+has come up).
+.TP
+.B up_sdnotify
+Use this option to run pppd in systemd service units of Type=notify
+(\fBup_sdnotify\fR implies \fBnodetach\fR).
+When \fBup_sdnotify\fR is enabled, pppd will notify systemd once
+it has successfully established the ppp connection (to the point where
+the first network control protocl, usually the IP control protocol,
+has come up). This option is only availble when pppd is compiled with
+systemd support.
+.TP
+.B usehostname
+Enforce the use of the hostname (with domain name appended, if given)
+as the name of the local system for authentication purposes (overrides
+the \fIname\fR option). This option is not normally needed since the
+\fIname\fR option is privileged.
+.TP
+.B usepeerdns
+Ask the peer for up to 2 DNS server addresses. The addresses supplied
+by the peer (if any) are passed to the /etc/ppp/ip\-up script in the
+environment variables DNS1 and DNS2, and the environment variable
+USEPEERDNS will be set to 1. In addition, pppd will create an
+/etc/ppp/resolv.conf file containing one or two nameserver lines with
+the address(es) supplied by the peer.
+.TP
+.B user \fIname
+Sets the name used for authenticating the local system to the peer to
+\fIname\fR.
+.TP
+.B vj\-max\-slots \fIn