+.B ipv6 \fI<local_interface_identifier>\fR,\fI<remote_interface_identifier>
+Set the local and/or remote 64-bit interface identifier. Either one may be
+omitted. The identifier must be specified in standard ascii notation of
+IPv6 addresses (e.g. ::dead:beef). If the
+\fIipv6cp-use-ipaddr\fR
+option is given, the local identifier is the local IPv4 address (see above).
+On systems which supports a unique persistent id, such as EUI-48 derived
+from the Ethernet MAC address, \fIipv6cp-use-persistent\fR option can be
+used to replace the \fIipv6 <local>,<remote>\fR option. Otherwise the
+identifier is randomized.
+.TP
+.B active-filter \fIfilter-expression
+Specifies a packet filter to be applied to data packets to determine
+which packets are to be regarded as link activity, and therefore reset
+the idle timer, or cause the link to be brought up in demand-dialling
+mode. This option is useful in conjunction with the
+\fBidle\fR option if there are packets being sent or received
+regularly over the link (for example, routing information packets)
+which would otherwise prevent the link from ever appearing to be idle.
+The \fIfilter-expression\fR syntax is as described for tcpdump(1),
+except that qualifiers which are inappropriate for a PPP link, such as
+\fBether\fR and \fBarp\fR, are not permitted. Generally the filter
+expression should be enclosed in single-quotes to prevent whitespace
+in the expression from being interpreted by the shell. This option
+is currently only available under NetBSD, and then only
+if both the kernel and pppd were compiled with PPP_FILTER defined.
+.TP
+.B allow-ip \fIaddress(es)
+Allow peers to use the given IP address or subnet without
+authenticating themselves. The parameter is parsed as for each
+element of the list of allowed IP addresses in the secrets files (see
+the AUTHENTICATION section below).
+.TP