On the Host side, inheritance and overrides are involved but straightforward:
If a host transaction profile parameter setting is not explicitly overridden, then: settings for its business parameters are inherited from the host business action; settings for its delivery parameters are inherited from the host delivery action; and settings for its transport parameters are inherited directly from the host transport.
If a host business or delivery action setting is not explicitly overridden, then settings for its parameters are inherited from its host action group.
If a host business or delivery action group setting is not explicitly overridden, then settings for its parameters are inherited from its host business or delivery protocol.
If a host transport/business/delivery protocol setting is not explicitly overridden, then settings for its parameters are determined by the attribute definitions built into B2B Host in Enterprise Designer.
Host transport settings inherited from the B2B Host built in Enterprise Designer are also affected by eWay configuration settings. If an eWay configuration parameter is not set, its value is determined by the configuration settings for the corresponding external system in the Environment.