The problem is that the variable you haven't provided is the most important
variable of all: how scalable is the web service that you are writing?
If your service simply adds two numbers, you should be able to service
thousands of transactions every minute. If your service does a db lookup,
that number drops to hundreds. If the service calls active directory, it
can drop further still. You need to create the service and then stress it
to see how many transactions you will be able to support per server.
Very few people have created services that are so heavily hit that they need
more than a handful of web servers. Since most web services are simple and
stateless, and they never have graphics like a web app does, then they
perform far better than web pages do from a transactional standpoint. I
would state that your web services should be able, as a rule of thumb, to
handle 200-400 "average" web service transactions per minute at normal load,
assuming db lookups and some logic. If you are going over HTTPS, that
number drops substantially, to something less than 125 encrypted
transactions per minute.
If you need a highly reliable and scalable system, place a hardware load
balancer with firewall (see products from F5 corporation, or Microsofts ISA
server) in front. To remove single points of failure, you'd need much more:
two switches, two routers in an HSRP configuration, and multiple ISP
connections. Your colo facility should provide the pairs of routers and the
multiple ISP datapaths. Oh yes, and put your load balancers in a "High
Availability Cluster." Most people don't need this level of redundancy,
but if your business is transactions on the internet, you might. Of course,
making the system reliable and highly available may require more than just
redundant web servers... if you are using a database, you may wish to
cluster the db servers as well.
And then, to keep the data available for the clustered servers, you could
invest is a modest SAN, which provides multiple hot-swap RAID drives in Raid
1+0 configuration, (I personally like McData, but other SAN providers are
very good as well).
I hope this helps,
--- Nick
"Peter" <Pe***@discussions.microsoft.com> wrote in message
news:80**********************************@microsof t.com...
How do I doing the sizing for .NET? Is there any methodology, spreadsheet
or questionair that I can use to estimate how many web servers, application
servers or database servers that have to be purchased in order to have
good performance
over the Internet?
"clintonG" wrote:
There are no specific hardware requirements for XML Web Services.
As a rule, the demand on the server(s) is always a matter of the demand
for the service itself.
--
<%= Clinton Gallagher, "Twice the Results -- Half the Cost"
Architectural & e-Business Consulting -- Software Development
NET cs*********@REMOVETHISTEXTmetromilwaukee.com
URL http://www.metromilwaukee.com/clintongallagher/
"Peter" <Pe***@discussions.microsoft.com> wrote in message
news:63**********************************@microsof t.com... If I want to build a web services application (not web application),
what is the hardware requirement ? Does anyone have the experience?
