|
Transport Agents The Transport Agents is found in the Edge Transport Agents and Hub Transport Agents roles, and has fundamental importance in the message security, regulation and hygienic process of Exchange Server 2007. The Exchange Server 2007 Transport Agents architecture allows all the flow of messages that pass through the Transport Agents pipeline to be processed by Transport Agents. The Transport Agents uses APIs that are available to vendors and the same APIs were used by Microsoft to deliver the standard Transport Agents which comes with Exchange 2007. Instead, in Exchange Server 2007 we use Transport Agents. When a message arrives in an Exchange Server organization, it is moved through the Transport Agent pipeline SMTP (Figure 01) and each SMTP Event may have Transport Agent that access the messages during this process and may perform some actions. The Transport Agent are used within Exchange Transport Agent Service and the only two roles where this service is available are Edge Transport Agent and Hub Transport roles. We are going to summarize all the built-in Transport Agent role by role, its priority and the SMTP Events associated an each Transport Agent. These standard Transport Agent were developed using the same APIs that can be used by 3rd party vendors. We can get a good example of the usefulness of Transport Agent when we have a single machine containing the three roles (Mailbox, Hub Transport Agent and Client Access) and that machine is responsible for all the Internet message traffic. In this case, the Transport Agent are responsible for the clean-up process (such as Anti-spam, content filter and so on). They are very useful in the Hub Transport role. Although the Hub Transport role has only two Transport Agent by default, we can use the script Install-AntiSpamAgents.ps1 which allows us to install some Anti-Spam Transport Agent, such as Connection Filtering, Content Filter agent, Sender ID agent, Sender Filter agent, Recipient Filter agent, and Protocol Analysis. By default, they are found only on the Edge Transport Agent Role. To install anti-spam Agent in the Hub Transport role, we must follow these steps:
|
