.PS 6i .ps 20 ## figure 3a B1: box "TCP/IP-only" B2: box invis with .w at (B1.e.x+linewid, B1.e.y) B3: box "``DUAL''" "" "TCP/IP" "" "FULL ISO" with .n at (B1.s.x, B1.s.y-lineht) B4: box "ISO-only" with .w at (B3.e.x+linewid, B3.e.y) ## line from B1.s to B3.n ## .PE