Archive for the ‘Edge Transport’ Category

Sender Authentication: Explained

October 11, 2007

Thanks Terry!! This is a great explanation of the technology for those of us who don’t want to wade through the volumes of text on the subject or for those of us that didn’t make it to Richi’s webinar earlier this year on the topic.

Of course, you should already be well aware of how this works if you run a mail system!! If you don’t and your running Exchange 2007, you may want to get familiar with a few cmdlets…. Test-SenderID can be used to validate incoming senderID information, Get-SenderID can be used to validate senderID information you have configured, and Set-SenderID can be used to set SenderID information for your organization.

Hosted eMail Services

February 16, 2007

There has been much debate and many new reports about hosted eMail services lately. A lot of this is due to the increase in SPAM, regulations, and viruses traversing the internet. MS has commissioned a paper on the benefits of hosted solutions over in-house messaging management….

David Spark asked me to look at this paper on Microsoft Exchange Hosted Services. From the looks of it, the same ask has been making the rounds to Terry Zink and Alec Saunders….but there aren’t very many opinions expressed on the wiki or the discussion group…I started to input my thoughts on the subject and the absense of supporting research…..

The paper itself seems to be based on Osterman Research work and there are some interesting research points that simply aren’t supportive of the claims in the paper. Some of the issues are…..

  1. In general the paper’s “findings” are not supported by the research quoted
  2. No discussion of the existing market is included
  3. No context is given for claims of cost savings or reliability
  4. Enterprise environments are not considerred
  5. Comparison against tenured appliances is not included
  6. Labor is generalized as high cost with no numbers to back it up

Now I’m sure there is plenty of data to support and refute the six items above in the context of hosted messaging services (especially in the case of the Microsoft Exchange Hosted Services)…..but they are not included in the paper and there is an opportunity to include them for people to see…..

So if you have an interest in hosted messaging components, you might want to take a look and ensure there is a consise opinion on the wiki fro the community (and other vendors) at large.

If you don’t have the time to comment, at least go vote on the hosting poll….

(results from the poll to be posted soon)

Exchange 2007 Edge

January 8, 2007

Exchange 2007 has been downloadable for a while now, this means a lot of you have had some time to play with it and start thinking about how you want to deploy it.

One of the design points is the Exchange Edge Server. Some time ago I wrote some details about this server role and asked how you thought you might deploy it. Now it’s time to check in and make your opinion heard!!

The question for the poll is:

Should the Exchange 2007 Edge Server Role reside behind a separate web facing appliance?

The current results are…..




Only because I already have a separate appliance


Either way, as long as the email gets through


No Way, The Edge role looks good so far




I’ll re-vote at RTM

Exchange Connections 2007

October 27, 2006

Paul is a busy guy, but he is taking the time to get the Exchange Connections conference organized for next spring. Everyone is buzzing about it already. That’s right this year’s fall connections hasn’t been held yet, but he is already getting ready for next years!

The Call for papers is out…..

If you want to present feel free to send your information to Paul.
If you don’t want to present, then let me know what you want to learn about, I am taking ideas for next year’s connections from you. Let me know what you want to know and the most voted for or best topic will be it

This could a panel like I’m planning for the local user group in december, information on a specific MS technology, information on a non-MS technology (storage, mobility – including blackberry or SyncML, etc), or information on implementations, cost justification, testing, etc…..just let me know

If you are in between wanting to present and wanting me to present your topic…. I am also offering a way for you to partner up with me or someone else to get on stage and present. That’s right, you get the experience, with a little help (I did my first presentation this way and it really made things easier).

Btw, if you are going to the Fall Exchange Connections 2006, be sure to stop by the Ferris Research Booth!

Get Free Technology Planning Advice

If you’re going to Exchange Connections and would like to meet Ferris Research, do get in touch. David Ferris, Lee Benjamin, and Bob Spurzem will be there November 7-9 at our booth, #222. The Exchange Connections registration page is here. It’s a good show for Exchange support staff.

Free Technology Planning Advice

We’ll be happy to provide free technology planning advice. Or if you’re a vendor, perhaps you’d like to brief us on your offerings and plans. We’re available as follows:

  • Tuesday, Nov 7
    • 5pm-7pm
  • Wednesday, Nov 8
    • 9am to 10:30am
    • 12:45pm to 2:30pm
    • 3:30pm to 5:30pm
  • Thursday, Nov 9
    • 10am to 11:30am
    • 12:30pm to 2:15pm

Exchange 2007 Edge Server Role

October 3, 2006

First…. rumor control….. no the edge role is not required for Exchange 2007…..

Now, the biggest question I get asked about the Edge role is regarding the redundancy. On a basic level most people want the edge role to be clustered, load balanced, or some other comforting idea. The reality is that Microsoft’s recomended approach is simply using round robin. There can be several Exchange 2007 edge servers in the network perimeter that service your organization. Using round robin allows administrators to easily add/remove edge servers, it also enables low-cost redundancy as all modern DNS systems support round robin. I would like to see load balancing as a supported option for customers who want to use it, but I have not seen or heard anyone testing or pushing for this yet.

So what does this mean to you? Is round robin sufficient? Well if the hub transport submits email to the edge transport and does not complete the SMTP conversation due to the edge server having a failure, the hub transport will retry the submission, with round robin the hub is likely to get a different server then it previously conversed with and therefore has a high likelihood of avoiding the previous issue. Of course this isn’t perfect and without active monitoring outbound email could certainly suffer. MS has not published much on this so I can expand if you REALLY need me to (they are working on it)

Here is a diagram from Microsoft’s site to help illustrate the scenario:

UPDATE: 2/13/07 –  apparently MS’s re-designed web site removed the gif….How do they ever expect anyone to hear a consistent message if they are always moving things around? You can get a diagram in PDF form from their site

So is this technology worth it? well there are no official numbers of messages/sec supported, but I have heard numbers with no rules (anti-spam, re-writes, etc) enabled that are comparable to enterprise appliances (e.g. Ironport & Ironmail) and numbers with all the rules enabled that are comparable with SMB appliances (e.g. Clearswift). So… somewhere in between is where most companies will be with their rule sets and somewhere in between should be the expected performance (at a much lower cost).

That leaves the security of the physical server…. I can not attest to this, I would love to hear about attempts to get into an Edge role that is properly configured though, if you have done this… drop me a line. The services are restricted and the database is offloaded to ADAM (to protect AD and the internal services). The Edgesync is ONE way (hub -> ADAM)… so ONLY SMTP goes through the firewall Edge -> Hub (more details here). Once the data is in ADAM, the Edge uses it’s own jet database to transport the email with lookups to ADAM for delivery instructions (including looking up blocked senders for every user, etc). This is interesting as the Edge server is essentially the hub transport server (using a jet database) with everything extra turned off, that is querying ADAM for delivery details (kind of the lightweight everything in the DMZ). Of course a lot of people are still worried about this, eWeek’s big review of Exchange 2007 stated edge SHOULD reside behind another appliance… hmm wouldn’t that add to the processing time… and as such the overall delivery time and add to the complexity of the environment?

What do you think about this technology? Go take the poll…..Should the Exchange 2007 Edge Server Role reside behind a separate web facing appliance?




Only because I already have a separate appliance


Either way, as long as the email gets through


No Way, The Edge role looks good so far




I’ll re-vote at RTM

So…. Cast your votes!!

Me? In general, I vote for NOT putting edge behind some other appliance, if you are going to use it…. get rid of your other gear and use edge…..otherwise, don’t use it. Of course every customer has their own scenarios and should carefully evaluate AND TEST the technology before implementing it…. so let us know what are your plans.