Exchange 2003 & Exchange 2007 Hosting: Whats the difference?

I have been writing exclusively on Exchange Hosting for a while here, I thought its time to mention some basics on Exchange Server itself. Hosting providers in the market are still selling Exchange 2003 based hosting, but most of them have now started offering Exchange 2007 based hosting services.

Lately If you have observed the news on the Internet, Microsoft and Google competition is heating up like anything. Especially, both companies are dominant in the email marketplace, where Microsoft dominates in the Enterprise and Google on the public side. When it comes to Email Hosting, Microsoft still has the market edge where Google already showed tough competition with Google Apps.

Back to the topic, if you are considering Exchange Hosting it is good to know about the current transition from Exchange 2003 to Exchange 2007. This information may not be relevant for an end user, but its a must know for the IT manager or consultant at the infrastructure side. Email with other collaboration tools is going through convergence and has also become a “top mission critical application” for many organizations.

Whats the real difference and benefits you get when your hosting providers replace Exchange 2003 with Exchange 2007?

The below table shows some highlights of the major changes in terms of roles, storage and processing power.

MS Exchange 2003 MS Exchange 2007
Runs on Windows 2000/2003 Runs on Windows 2003/2008
32-bit x86 Need 64bit (EM64T/AMD64)
2 Server Roles
  1. Back-end (Mailbox)
  2. Front End (OWA/ActiveSync)
Five Roles
  1. Edge Server or gateway is to manage Port 25 and hygiene functions.
  2. Bridgehead or hub is for policy management and transport functions.
  3. Unified messaging services is to incorporate PBX interface, voice mail and fax capabilities and its management.
  4. Client access services is basically to facilitate OWA, Active sync,OMA, RPC over HTTP, Web services etc.
  5. Mailbox services for mailbox and public folders.
5 Storage Groups maximum 50 Storage Groups per server on Enterprise Edition 5 Databases 50 Databases per Server on Enterprise Edition – (Maximum 5 databases per storage group)

It is obvious that most of the Exchange 2003 customers are staying on the same platform for some more time, while new customers take advantage of Exchange 2007 Hosting. The main reason for this transition delay is due to the fact that effort required to change from 32-bit to 64-bit hardware is higher.

“Standard and Enterprise Edition” in Exchange 2007 has big difference in pricing. So in a 5 role deployment scenario, you can pretty much restrict all the roles , except “Mailbox Server Role”, into Standard Edition. In Exchange 2003, “Standard Edition” was less useful for large organization because it only supports up to 16Gb storage capacity.

Another benefit worth pointing out is the lesser IOPS. With the benefits of 64-bit addressing, it generates only 75% fewer IOPS compared to Exchange 2003 on 32-bit. According to Radicati Group Study, “There will be more than 1.4 billion mailboxes in the year 2007 and that number will grow to 2.2 billion mailboxes in 2009, an average annual rate of 16%.” In another study they mentioned mailbox growth as below,


The above study justifies a move into an Exchange 2007 Hosting environment. Lets move on and see how Exchange 2007 has been improved in business continuity and backup.

In another study as per Meta Group Survey in 2003 “80% of organizations surveyed felt that access to e-mail was more important than the telephone…74% believed being without e-mail would present a greater hardship than losing telephone service.”

Exchange 2007 is full of “Business Continuity” features. Here is a glance,

  1. Local Continuous Replication – Using a single server, after logs are committed it ships from the active storage group on one disk system over to a passive copy on a secondary disk system. These logs in secondary system becomes passive copy and can be further backed up using VSS aware backup application.
  2. Cluster Continuous Replication – This is using two servers, and based on active/passive MSCS cluster technology. Node #1 is attached to the primary disk system, and after logs committed it ships to the disk (passive copy) attached to the Node#2
  3. Standby Continuous Replication – SCR is based on two independent servers in two locations. Very much like CCR, if the first server fails, scripts can be run to switch over to the second server. Each server has its own disk system.
  4. Single Copy Clusters (SCC) – This is the same OLD style clustering in Exchange 2003.

Significance of Archiving

Various compliance study estimated that majority of the organization’s intellectual property (IP) located in their email storage. Email is often requested in lawsuits and regulatory investigations. Hence the new regulations now mandate that emails are archived, protected against tampering and unauthorized access, and kept for a certain period, or until specific conditions are met. Here is a nice white paper on “Why organizations need to archive email”

Value additions may even become “Mission Critical”

Continuous research from Microsoft enabled the organization to reach its users beyond email (Outlook client). Some great examples are “Outlook Web Access” (provides browser-based access), “Outlook Mobile or Active-sync” (enabled PDA to connect back to organization Messaging Server) and “Outlook Voice Access” which allows you to listen to your emails from any phone. With unified messaging component and Office communications server, more people begin to telecommuting and eventually, these “value added services” are also become “Mission Critical” component.

Technorati : , , , , , , , : , , , , , , ,

Leave a Comment

Your email address will not be published.

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.

Scroll to Top