-in the set [-A-Z0-9_] in any order. Optionally, for extra routing to
-a specific end point (node or user), it may have another 12 character
-field in the same set, concatenated with the string, separated by a ':'
-character.
-
-This field is used either to indicate particular node destination
-or to differentiate this broadcast in some way by making this
-message as a member of a L</Group>. Any message can be sent
-down any L</Group>. The names of L</Group>s and their usage
-is entirely up to the implementor.
-
-It is assumed that node names can be differentiated from user
-names and L</Group> names.
-
-If the field is set to a particular node destination, it will
-be routed (rather than broadcast) to that node. However, any
-intervening nodes are free to duplicate the message and send
-it down more than one, likely looking, interface - depending on any
-network policies that may pertain.
+in the set [-A-Z0-9_/] in any order.
+
+Optionally, for extra routing to
+a particular L</Terminal> connected at a specific L</Node>, or even a
+particular L</Terminal> in a L</Group>,
+it may have another 12 character
+string in the same set, concatenated with the first string. The two strings are separated by a ':'
+character. For example:
+
+ DX # the DX group
+ GB7DJK # the node GB7DJK
+ G1TLH # the user or endpoint G1TLH
+ GB7DJK:G1TLH # the user G1TLH at GB7DJK
+ DX:G1TLH # the user G1TLH in the DX group
+
+This field can contain either a L</Terminal> or some other string which is interpreted
+as broadcastable group address. Any message that has a L</Group> that is not recognised as a L</Terminal> must
+be broadcast.
+
+This means that messages to callsigns, for whom no specific routing information is available,
+will be found by means of a broadcast. Hopefully this will cause some kind of activity o.b.o
+that callsign will allow routing tables to be gathered that narrow down the scope of any future
+message to that callsign through the network.
+
+Remember that not all L</Node>s may pass every L</Group> field, depending on local policy.