Your network contains an internal network and a perimeter network that are separated by a firewall. The perimeter network contains an Exchange Server 2010 Edge Transport server. 
You plan to deploy an internal Exchange Server 2010 organization that meets the following requirements：.Support EdgeSync synchronization
.Support encrypted delivery of outbound e-mail messages to the Edge Transport server .Minimize the attack surface of the internal network 
Which TCP ports should you allow from the internal network to the perimeter network？（）

Your network contains a single Active Directory domain. 
You have an Exchange Server 2010 organization that contains a Hub Transport server named Hub1. Hub1 receives all e-mail messages that are sent to your organization from the Internet. 
A new company security policy states that domain-joined servers must not be accessible directly from theInternet. 
You need to create a message hygiene solution to meet the following requirements：
.Comply with the new security policy
.Minimize the amount of spam that is delivered to the internal Exchange servers in the organization
What should you do first？（）