White paper on the benefits of multi-site, and when it is the right choice for your organization.

1. When to Use a Multi-Site
Architecture
Exploring the Benefits of Multi-Site for Your Next Web
Project
commonplaces
Strategy Creativity Technology
Inside:
Introducing Multi-Site ............................ 2
What Is Multi-Site? ................................ 3
Why Use Multi-Site ................................ 4
When Not to Use Multi-Site ................... 7
Project Planning ..................................... 8
Summary and Next Steps ....................... 9
.

2. Introducing Multi-Site
More often than not, one website can deliver everything an organization needs,
and help them achieve all of their goals.
In some cases, however, your goals may necessitate multiple, related websites.
Perhaps you want to build upon the success of your resource site for plumbers,
and offer one for electricians as well. Maybe you want to create an online
university, separate from your main site, and offer courses to your current
users. Or maybe you want to customize multiple online stores for different
segments of your customer base, but offer many of the same products to them.
In these examples, the solution is to
create multiple, distinct websites.
However, in each case, these separate
sites share some information or
functionality. It would save a significant
amount of time, money, and frustration
if you could build these separate
sites on a common base, sharing the
information that needs to be shared,
and customizing the pieces that are meant to be unique.
Fortunately, you can.
© 2010 CommonPlaces e-Solutions, LLC | www.CommonPlaces.com 2

3. What is Multi-Site?
A multi-site is multiple websites that are connected in some way. You can think
of separate websites, with nothing connecting them, as looking something like
this:
Site A Site B Site C
Database Database Database
But what if you want to share data between sites? Or perhaps your sites will
share much of the same look and functionality. In both cases, it would be easier
and more cost-efficient to build a multi-site architecture, which would look
something like these:
Shared
Codebase Site A Site A Functionality
Site B
Site B
Database Database
Database
© 2010 CommonPlaces e-Solutions, LLC | www.CommonPlaces.com 3

4. Why Use Multi-Site?
A multi-site solution promises a savings of time and money in the development
of your project. Why? Because every piece of your project that is shared
between multiple sites only needs to be built once, rather than repeated across
multiple websites.
As an example, both Sony and Warner Brothers Records use Drupal multi-sites
to create websites for their musical artists. Because each artist’s site is made up
of essentially the same pieces (blog, news, tour dates, pictures, etc.), they can
replicate this functionality as many times as they need, rather than building it
from the ground up every time.
Multi-site delivers a big savings in your maintenance costs, as well. If your
multiple sites share a database, the cost of maintaining your data will
be reduced. As platform updates are released, they will only need to be
implemented once, instead of once for each site.
The cost savings of multi-site are clear. But there are actually many other
reasons to build a multi-site solution. In fact, multi-site can deliver valuable
functionality that cannot be recreated with multiple, separate sites.
© 2010 CommonPlaces e-Solutions, LLC | www.CommonPlaces.com 4

5. Why Use Multi-Site?
If you plan to create multiple related websites, a multi-site solution can offer a
significant savings in development and maintenance costs. But there are other
reasons why a multi-site may be the best fit for your needs. Here are a few
examples:
Provide cross-site searching. If you plan to offer content spread across multiple
sites, the ability to search for content across sites would provide a much better
user experience. That is, a search on one site would return results from all
of your sites. Web users have become very accustomed to using search, and
helping them find the content they’re looking for will result in less frustration
and higher user retention.
Single Sign-On
Offer a Single Sign-On. Many of our multi-site
Username
clients want their users to be able to use the same
user name and password across multiple websites.
Password Single Sign-On makes your sites easier for your
visitors to use and interact with. The value of
usability can never be understated, and making
Log In your users create three (or more) distinct accounts
for your separate websites is not user-friendly.
© 2010 CommonPlaces e-Solutions, LLC | www.CommonPlaces.com 5

6. Why Use Multi-Site?
Use a shared e-commerce path. Managing multiple e-commerce stores is no
easy feat. Between SSL Certification, PCI Compliance, and payment gateways,
creating and managing a successful online store can be a challenge; managing
four can be next to impossible. With a multi-site solution, you can direct
multiple online stores through one shopping cart, greatly reducing the amount
of time and effort needed to stay compliant with online merchant regulations.
At the same time, this solution will make it easier for users to purchase items
from multiple sites with a single order, making your sites more usable and
encouraging your customers to buy more. Meanwhile, it will be easier for you
to dynamically manage inventory across stores.
Lastly, a shared e-commerce path makes it possible to
recommend products from one site as your customer
is making a purchase on another. Perhaps you know
that many of your customers who buy Product X also
buy Product Y, or that they would, if they only knew it
existed. Recommended products, or “Our Customers
Also Like...”, is your chance to tell them.
© 2010 CommonPlaces e-Solutions, LLC | www.CommonPlaces.com 6

7. When Not To Use Multi-Site
Although a multi-site solution can offer a lot of great benefits, it is by no
means right for every website and every organization. Consider the following
questions:
Could your goals be accomplished by one website? While our experience
shows that multi-site offers a significant savings in time and money over
multiple websites, a single website is obviously the least costly option. In most
cases a single website will be a more usable solution for your visitors if there is
no specific reason to create multiple sites.
How similar are your separate sites? So you’ve determined that you goals
clearly demand multiple websites. But what do they have in common?
The multi-site approach is based on the premise that time can be saved by
replicating similar content, architecture, or functionality. But if your separate
sites share none of these things, there is little to be gained by pursuing a multi-
site solution.
Will multi-site create obstacles for my site? In the open source world, a lot of
website functionality is created through pre-existing modules of code. However,
not all modules are built to work correctly in a multi-site environment. Before
choosing multi-site, you (and/or your development partner) should consider
which modules are needed, and if these will work smoothly in a multi-site
scenario.
© 2010 CommonPlaces e-Solutions, LLC | www.CommonPlaces.com 7

8. Project Planning
Because of the added layer of complexity that multi-site brings to a project, it
is critical that the needs, goals, and objectives of your related websites are
clearly established before development begins.
For example, some multi-sites rely on a single database; others are based on
multiple, related databases. There are advantages and disadvantages of both
approaches; the right choice for you can only be found after a complete look at
the desired functionality of your websites.
A complete planning process prevents any
miscommunication between client and
developer, and avoids costly changes in the
project’s direction. A clear understanding
of the project from the beginning will
prevent these changes in course, and
ensure a smooth development process.
Lastly, a word of caution. A multi-site installation is a more complex and
challenging endeavor than building a single site. Make sure that you locate a
capable developer, with experience building multi-sites, to build your project.
Do not trust your future success to an inexperienced development team.
© 2010 CommonPlaces e-Solutions, LLC | www.CommonPlaces.com 8

9. Summary and Next Steps
Multi-site is a powerful Web development tool. If your goals require multiple
websites, creating them within one multi-site structure offers a great savings
in both the development and maintenance costs of your project. But before
deciding on multi-site, ensure that it is the right solution for your needs,
considering the questions posed on Page 7 of this document.
The development experts at CommonPlaces excel at accurately and completely
planning Web projects, and can guide you to the appropriate multi-site solution
for your needs. We completed out first multi-site project in 2004, and since
then we have grown immensely, along with technology, to achieve great
improvements in multi-site implementation.
Many open source platforms support multi-site architecture. Most often, we
build multi-site projects with the Drupal Content Management System. There
are many reasons why we feel Drupal is the best choice for our clients. Want to
learn more about Drupal?
If you would like to talk more about multi-site technology and Drupal, or discuss
your next Web project, feel free to contact us.
Lastly, please share this document with others who would like to learn more
about the benefits of a multi-site solution.
© 2010 CommonPlaces e-Solutions, LLC | www.CommonPlaces.com 9