# IT cost containment: Terminal Computing

Before I get started, I'd like to invite you to leave a comment requesting a cost analysis for something you might be considering.  For anything that I can reasonably develop, I'll do so in this space.

For this posting, I'm making the following assumptions:

• A typical PC is on a 3 year replacement cycle. I'll use a figure of \$700 for each PC. As far as power consumption goes, let's assume that each PC is on for 8-10 hours per day and consumes around 100 watts of electricity (http://checker-board.blogspot.com/2006/12/computer-power-consumption.html). Our sample organization is has 99 PCs on this replacement cycle and each PC is used about 220 days per year. I'm not going to consider monitors in my calculations since you need them regardless of whether you're using terminals or PCs, so they result in no cost difference.
• A replacement terminal is on a 6 year cycle. Since terminals often contain no moving parts, this is feasible. I'll use a figure of \$350 for each terminal. For power, again, these units will be used for 8 to 10 hours per day and consume around 10 watts of power (http://www.computerlab.com/techspecmt15g.htm). Terminals are used about 220 days per year.
• Terminal servers are also on a 3 year replacement cycle. Reasonably configured, I'll use a figure of \$7,000 for each server. For this example, let's use a Dell PowerEdge 2950 rev III server like I did in my previous posting. Since I don't know what Dell might release three years from now, all I have to use for calculation is what exists today. I'm assuming that each server has two mirrored drives for booting the OS and 8GB of RAM. Each PowerEdge 2950 server consumes 323.3 watts or power, which I'll round to 325 watts for the purposes of my calculations. Five servers will handle the workload. Assumption: 25 terminals per server with a fifth thrown in as a spare. The servers run 24x7x365.
• As per the information located at http://www.eia.doe.gov/cneaf/electricity/epm/table5_6_a.html, I'll use the November 2007 figure of 9.6 cents per kilowatt hour average for commercial power in the United States. I won't be accounting for inflation in electrical costs in this scenario.

And now, on to the calculations, which I'll break down by year over six years.

 Desktop scenario Year 1 Year 2 Year 3 Year 4 Year 5 Year 6 Total 99 PCs/3 yr 69,300 0 0 69,300 0 0 138,600 Power (9 hrs/day) 1,882 1,882 1,882 1,882 1,882 1,882 11,292 Total 71,182 1,882 1,882 71,182 1,882 1,882 149,892 Terminal scenario Year 1 Year 2 Year 3 Year 4 Year 5 Year 6 Total Terminals (99/6 yr) 34,650 0 0 0 0 0 34,650 Servers 35,000 0 0 35,000 0 0 70,000 Term'l power (9 hr) 188 188 188 188 188 188 1,129 Server pwr (24 hr) 1,367 1,367 1,367 1,367 1,367 1,367 8,199 Total 71,205 1,555 1,555 36,555 1,555 1,555 113,978 Terminal savings Year 1 Year 2 Year 3 Year 4 Year 5 Year 6 Total Savings (23) 327 327 34,627 327 327 35,914

Under the scenario outlined, there is a rather substantial savings to be had by moving to a terminal computing environment.  Not much is saved in power due to the need to operate servers 24/7, but eliminating the year 3 PC replacement saves a lot.

Again, this is a very generic, very rough scenario in which I've had to make a huge number of assumptions.  It does, however, provide a possible outline for you to work with when you consider your desktop computing environment.

Since 1994, Scott Lowe has been providing technology solutions to a variety of organizations. After spending 10 years in multiple CIO roles, Scott is now an independent consultant, blogger, author, owner of The 1610 Group, and a Senior IT Executive w...

Pazman

I'd like to see a comparison betwen competing back-ends for thin client computing: - Virtual desktops using VMWare on high-end servers - Terminal services/Citrix on top of Windows servers - Dedicated low-cost blade PCs (HP's consolidated client infrastructure is one example) It's not so much that thin client computing can save you money, but which back-end to use with it.

jon_saxon

Scott Lowe

You are definitely correct on all points. There are a huge numbe rof variables to consider in all of the scenarios I put forth. I try to make them simple to a point, but with enough information to see the picture. As some pointed out, I did not include TS CALs either. Simply put, TS CALs are priced radically differently depending on the vertical. In higher education as a part of a campus agreement, they might as well be free, but in a corporate environment, not so much. These are very much intended to be starting points for discussion -- nothing more. Also, I do think that the right terminal can serve for six years as long as it's upgradable from a software perspective to support newer protocol versions. That is also assuming, as you point out, that your infrastructure/desktop environment doesn't have to undergo a paradigm shift at some point in the cycle.

stod73

I'm not an expert on Windows 2003 Terminal Server CALs but it must be noted that there would be a significant cost for licensing to use terminal computing. I also think it's important to point out that you would most certainly need an IT professional on staff that understands TS and have the ability to administer. There will also need to be a fair amount of training for the user community to understand this new environment. Between CALS, training and upgraded staff you will have most likely ate up any savings achieved buy going thin. But don't get me wrong. If you can go thin I highly suggest it. Software deployment is superior. User downtime is almost non-existent. All and all a better system for any infrastructure team.

Forum Surfer

Forgive me but I didn't read (nor did I go back and re-read) your previous post. How did you go about obtaining your power consumption figures? I say this only because I've taken reading before that turned out a bit different (granted all things should turn out different, but not this drastically). I did some calculations on the cost of installing switchable power strips to save cost after hours. I used a very accurate fluke meter with a wrap-around lead to measure my actually amps. After several calculations the wattage saved was severely offset by the purchase of switchable strips or outlets. But even still, the difference was very small in the actual power bill (barely enough to notice) for standby vs off completely. I'm not disputing you by any means, I just wanted to see how you arrived at your figures since I had performed similar studies. Just a thought...I liked your article, however. For me I have too many apps that aren't TS friendly to even contemplate going that route. Nevermind the fact that I am not a big fan of it!

glennj

I've been running terminals in a school district since 2004. I bought 500 TS CALs for \$325 - can't remember if education got a discount for this or not. I did no training for this environment, as it wasn't necessary. Students just said, wow, these computers are really small! End users could tell no difference - all they had to do is click an icon on the desktop that started the RDP session.

Scott Lowe

Regarding TS CALs - very good point. I should have included that in my analysis. Of course, if the organization wants to avoid TS licensing, they could do VDI using Virtual Server 2005 and just use Remote Desktop from a terminal to access individual VMs. I also agree with the need for good IT folks to pull this off!!! Scott

wdewey@cityofsalem.net

Wouldn't using virtual machines automatically cut down the number of total users a server could support? Also, VM's probably require some type of Desktop licensing that would need to be factored in.