The basic EAI concepts involve exchanging mail in UTF-8. Though the original proposal included a downgrading mechanism for legacy systems, this has now been dropped. The local servers are responsible for the local-part of the address, whereas the domain would be restricted by the rules of internationalized domain names, though still transmitted in UTF-8. The mail server is also responsible for any mapping mechanism between the IMA form and any ASCII alias.
Availability, price and employee familiarity often determines which operating systems are offered on dedicated servers. Variations of Linux and Unix (open source operating systems) are often included at no charge to the customer. Commercial operating systems include Microsoft Windows Server, provided through a special program called Microsoft SPLA. Red Hat Enterprise is a commercial version of Linux offered to hosting providers on a monthly fee basis. The monthly fee provides OS updates through the Red Hat Network using an application called Yum. Other operating systems are available from the open source community at no charge. These include CentOS, Fedora Core, Debian, and many other Linux distributions or BSD systems FreeBSD, NetBSD, OpenBSD.
Ultimately, it boils down to a balance between cost, features, and risk. It's always tempting to simply jump on the lowest-cost solution, but the fact that email is ubiquitous keeps this from being the smart play. It's nearly impossible to escape using it, which means your users, your customers, and the guts of your business have all come to depend on it in different ways. You need to discover those ways, evaluate them, and then choose a service that either meets or improves on them. This takes time, discussion with your IT staff, and some investigation; these are steps you don't want to skip. Otherwise, you'll pay for it later.
Hosted email often comes as part of another service, such as web hosting or Infrastructure-as-a-Service (IaaS). Since that means there will be many extras available with these services, it's inescapable that you'll be paying for those extras in some way. Purchasing them usually means a slight uptick in that per-user price. Many businesses find that, once they're done selecting all of their needed "optional extras," their end price can often reach as high as $10 or more per user. This can start to add up for larger teams. It's somewhat like buying cable service: sometimes you need to pay for the channels you don't want to get the couple of channels that you need. There is also the old adage that "you get what you pay for" when it comes to quality. This is almost always true when considering an email host.
Additionally, there are a few ways to improve the security of the visitors coming to your website. An SSL wildcard certificate comes with every domain. If you would like to know more about our SSL certificates, check out our product specs. Shortly, we will be introducing the Domain Guard in order for you to be able to protect yourself from DNS hijacking.