19.2.3.4. Domains 
It may be necessary to subdivide a very large enterprise network into
several areas (domains) where DMC is only possible within a domain and
not between domains.
In order to achieve this an LCR mark has to be set at each domain
end. When this mark is set DMCs are not established beyond this point.
AMO command:
CHANGE-LDAT:LROUTE=<route number>,LATTR=<existing attributes>&DMCEND;