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The interoperable object group references contain profiles that address server object groups. This section illustrates the
use of these profiles according to one of two modes:
• Profiles that address object group members.
• Profiles that address gateways (technically generic in-line bridges of the type described in the Building Inter-ORB Bridges chapter of the CORBA specification).
The choice of addressing mode is influenced by the Replication Style of the object group.
23.2.4.1 Profiles That Address Object Group Members
When using profiles that address members of an object group, the object group reference for a server object group contains
one TAG_INTERNET_IOP profile for each member of that group. Each profile contains a member reference that can be used to reach
an individual member of the object group.
23.2.4.2 Profiles That Address Gateways
When using profiles that address gateways, the object group reference for a server object group contains one TAG_INTERNET_IOP
profile for each of several alternative gateways to that group. Each profile contains a reference to a gateway that can forward
messages to all members of the server object group possibly using a proprietary multicast group communication protocol. The
group communication protocol may be used for server object groups that support any of the Replication Styles.
23.2.4.3 Choice of Profile Addressing Mode
For a server object group having the STATELESS, COLD_PASSIVE, or WARM_PASSIVE
Replication Styles (Section 23.3, “Replication Management,? on
page 23-31), the Fault Tolerance Infrastructure at the server may create either an object
group reference that contains member profiles, or alternatively, an object group reference that contains gateway profiles.
For a server object group having the ACTIVE and ACTIVE_WITH_VOTING (
Section 23.3.2, “Fault Tolerance Properties,? on page 23-32) Replication Styles, the
client must invoke all of the members of the server object group simultaneously so that the members are treated as, and behave
as, peers in executing the methods invoked on the object group. Therefore, for the ACTIVE and ACTIVE_WITH_VOTING Replication
Styles, the Fault Tolerance Infrastructure at the server can create an object group reference that contains profiles for gateways
that multicast the request to all of the members of the object group.