Example of Transaction Replication with Immediate Updating Subcribers

Figure 32-9 shows a transactional replication with immediate updating subscriber topology
in a trading environment.

Because all the SQL Server 2005 instances are located on the same fast, reliable LAN,
we can take advantage of the (DTC) technology.
In this scenario, a user making a change to the back office subscribers database
invokes a distributed transaction with the front office publisher.
This transaction then remains to be replicated to the middle office subscriber.

Source: Microsoft SQL 2005 Administrator's Companion,
Page 1105