This is the Relative Name (RN) of the communication-policy control object for the UCS domain, the single naming component that distinguishes this Communication instance from its sibling instances under the same parent object. UCS Manager appends this RN to the parent's DN to build the full path, so it is the piece an admin checks when several Communication instances exist side by side and need to be told apart, because its source field shows whether current communication settings came from local policy or an external controlling authority. For a domain where UCS Central, not the local administrator, is pushing communication policy, if two Communication instances share the same parent, this RN is the one field that tells an admin which of the two a given SNMP row is actually describing.