Does Exchange 2013 need an edge transport server?

Though server roles were consolidated in Exchange 2013, one reader wonders if an edge transport server should still be included. Our expert weighs in.

I'm considering migrating to Exchange Server 2013. I understand that the Exchange server role structure has changed to the point that now, only the client access server and mailbox server roles are left. I've done a bit of research and am curious to see if Exchange 2013 actually needs an edge transport server. Can you please advise?

You're right in that Microsoft simplified the concept of server roles in Exchange Server 2013. Where Exchange 2007 and Exchange 2010 had five server roles -- the client access server (CAS), unified messaging server, hub transport server, mailbox server and edge transport server -- Exchange Server 2013 only has two: the client access server role and the mailbox server role.

As you know, the edge transport server helps protect an Exchange organization from viruses and spam, so I can see why you're wary about Exchange 2013 lacking an edge. Depending on your configuration, you may still need to provide edge security to your Exchange 2013 deployment. It all depends on if your deployment consists solely of Exchange 2013 servers, or if you still plan on having Exchange 2007 or Exchange 2010 servers in your organization.

If you still plan on using your Exchange 2007 or Exchange 2010 edge transport server, you must make sure that your edge transport servers are connected to a hub transport server.

If you're planning on a pure Exchange 2013 deployment, external email enters the Exchange organization through a CAS. The CAS does preliminary filtering -- which was previously handled by the edge -- before routing the message to the transport service, which now runs on mailbox servers.

About the author
Brien Posey is a ten-time Microsoft MVP with two decades of IT experience. Before becoming a freelance technical writer, Brien worked as a chief information officer at a national chain of hospitals and health care facilities. He has also served as a network administrator for some of the nation's largest insurance companies and for the Department of Defense at Fort Knox.

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