Getting Smart (Smarthosts that is)

No matter what version of Exchange Server you’re using – or even if you don’t use Exchange at all – you need to perform message hygiene on all mail in your organization.  Virus files, spam, phishing schemes and tons of other attacks are thrown at every email domain, every day.  If you’re not ready to deal with them, you’re dead in the water.  Smaller companies often just make due with hygiene software on the Exchange Server itself, but all sized firms need solution sets, and even smaller firms can take advantage of Smarthosts in a few different ways.

Smarthosts are servers or hosted solutions that are dedicated to performing message hygiene on all mail coming and going from your organization.  They come in many flavors, but tend to center around three types:

1 – Fully hosted solutions.  This method has no Smarthost hardware on-site, but instead contains everything at a hosting provider’s location.  Lowest up front cost, but highest ongoing (monthly, quarterly, etc.) costs.

2 – Hybrid solutions.  Here, you host a small appliance on-site to handle some of the workload, with the rest of the message hygiene functions handled by the service provider in their facility.  This isn’t quite as popular as the other two solutions, as the costs can quickly outweigh the benefits.

3 – Fully owned solutions.  Appliances and servers are in your datacenter, and totally controlled by you.  Start up costs are high, but ongoing costs are very low, as you’re only paying for updates to the virus/spam filter engines.

For smaller organizations, hosted solutions allow you to assign your Mail eXchanger (MX) record  to point to your Smarthost partner’s datacenter.  There, all incoming mail will go through the filters and checkers before it ever reaches your internal server set.  Most hosted providers allow you to update a list of “known good” recipients, so that any mail not destined for a valid employee is rejected immediately.  Virus scans are performed, and optionally spam filtration happens as well.  The remaining mail goes off to your internal mail servers for delivery to the end-users.

When mail leaves your organization, your internal servers are configured to send it first to the Smarthost provider, instead of directly to its destination SMTP servers.  The service provider performs all the same message hygiene on those messages, then acts as the SMTP gateway for your domain out to the rest of the world.

Hybrid solutions do everything that the fully hosted solutions do, but typically place a small appliance on-site to do periodic scans of the mail server itself.  They can also help speed up the whole process by making the “first hop” for email flow out of the organization be local instead of across the WAN.  It’s rare to see a hybrid Smarthost system that only does email hygiene, as the fully hosted or fully owned methods are much better for this kind of single-task solution.  Instead, the appliances on-site will typically handle all anti-malware processes including updating desktop protection and server scanning.

Fully owned solutions place appliances and/or other equipment at your production facility.  They act the same as the hosted solution, but you own all of the hardware and pay only for periodic updates to virus definitions, malware profiles and spam allow/deny lists.  This solution offers much more flexibility than a hosted solution, as you have complete and immediate control over any changes that might need to be put into effect.  The drawback is that if the hardware needs to be upgraded, you’ll be responsible for buying the new boxes.

Smarthosts are available from a large number of vendors.  Postini, Barracuda, and Microsoft Exchange Edge Services are just three that can be found with a Bing Search.  Most perform the same tasks, but each has their own selling points.  Your best bet is to talk with multiple vendors and see which one has the solution set closest to what you need.  Ask about things like ease of administration, web or application interfaces, ability to create custom allow/deny lists, and integration with your own Domain services to get updates to users and allowed accounts without compromising security on your AD servers.

No matter which vendor you choose, or which solution, using a Smarthost removes the message hygiene load off the Exchange Servers, which is always a good thing to do.  By dedicating either a service or server to handling message filtering and security, you can free up resources to provide a better end-user experience and a safer messaging environment.