You will be automatically enrolled in Medicare Parts A and B effective the month you turn 65. If you do not receive Social Security benefits, then you will need to sign up for Medicare by calling the Social Security Administration at 800-772-1213 or online at http://www.socialsecurity.gov/medicareonly/ .
The Client Access Server (CAS) is installed by default. Plan to have a Client Access server in each site that has an Exchange 2010 mailbox server. Your main clients will probably be desktop machines running Microsoft Outlook. Other client types include POP3, IMAP4, Exchange ActiveSync, Web, and Outlook Anywhere.
Exchange Server 5.5 uses two ports, one each for the information store and the directory. Microsoft Exchange 2000 Server and Exchange Server 2003 use three ports, one for the information store and two for the system attendant, respectively. Alternatively, Microsoft Outlook 2003 can use RPC over HTTP to connect to servers running Exchange Server 2003.