You are the messaging engineer for your company. Your company has a main office and five branch offices.

Each office has three Exchange Server 2007 servers. Two Mailbox servers are configured as a single copy cluster. The third server is configured a Hub Transport server.

During a recent Hub Transport server failure, some Microsoft Office Outlook users reported that they were unable to send or receive messages.

You need to design an Exchange organization that meets the following requirements:

Ensure that the failure of a Hub Transport server on the network does not prevent message delivery.

Load balance the delivery of messages between multiple Hub Transport servers in each office.

What should you do?