-.IR ifconfig :
-.TP 15
-.B up
-Mark an interface ``up''.
-This may be used to enable an interface after an ``ifconfig down.''
-It happens automatically when setting the first address on an interface.
-If the interface was reset when previously marked down,
-the hardware will be re-initialized.
-.TP 15
-.B down
+.Nm ifconfig :
+.Bl -tag -width dest_addressxx
+.It Cm alias
+Establish an additional network address for this interface.
+This is sometimes useful when changing network numbers, and
+one wishes to accept packets addressed to the old interface.
+.It Cm arp
+Enable the use of the Address Resolution Protocol in mapping
+between network level addresses and link level addresses (default).
+This is currently implemented for mapping between
+.Tn DARPA
+Internet
+addresses and 10Mb/s Ethernet addresses.
+.It Fl arp
+Disable the use of the Address Resolution Protocol.
+.It Cm broadcast
+(Inet only)
+Specify the address to use to represent broadcasts to the
+network.
+The default broadcast address is the address with a host part of all 1's.
+.It Cm debug
+Enable driver dependent debugging code; usually, this turns on
+extra console error logging.
+.It Fl debug
+Disable driver dependent debugging code.
+.It Cm delete
+Remove the network address specified.
+This would be used if you incorrectly specified an alias, or it
+was no longer needed.
+If you have incorrectly set an NS address having the side effect
+of specifying the host portion, removing all NS addresses will
+allow you to respecify the host portion.
+.It Cm dest_address
+Specify the address of the correspondent on the other end
+of a point to point link.
+.It Cm down