Citrix MetaFrame is
widely used today to provide users with
access to critical business applications
via server-based computing and Terminal
Server technologies. However, now that
Microsoft’s .NET application strategy is
beginning to mature, many people have
openly wondered about the future of
Citrix and their MetaFrame product line.
How will Citrix MetaFrame fit into a
.NET world, given that .NET applications
inherently contain many of the features
that make Citrix attractive in the first
place?
This paper is not yet
another feature-by-feature comparison of
Citrix MetaFrame and Microsoft Terminal
Server. Instead, it focuses on the
fundamental application delivery
architectures and the concept of
server-based computing versus .NET
applications.
Application Access
and Usage Challenges
Before we can fully
analyze whether future applications will
be accessed via server-based computing
(Citrix MetaFrame) or Microsoft’s .NET
technology, we need to identify the core
business issues that these technologies
solve. There are six major challenges
that must be addressed when deciding how
end-users will access their critical
business applications:
-
Application
installation and configuration.
-
Prerequisites and
requirements of client devices.
-
Bandwidth
requirements.
-
Application
compatibility.
-
Application access
from outside the firewall.
-
Security.
Citrix and Microsoft
each address these challenges in their
own unique ways. Let’s look at how each
does it, beginning with Citrix.
How Citrix Addresses
Traditional Application Challenges
Microsoft Terminal
Services allows existing 32-bit Windows
applications to be accessed via remote
devices. Even though Citrix MetaFrame
extends and adds to Terminal Services’
capabilities, MetaFrame leverages the
same fundamental application
architecture. Therefore, for the
purposes of this discussion, the two key
elements of Citrix MetaFrame’s
technology are:
How Microsoft .NET
Applications Address Traditional
Application Challenges
Microsoft’s .NET strategy describes how
components will exist and work together
using the Internet, web services,
servers, and many different types of
client devices. This strategy is being
implemented through the release and sale
of several Microsoft products.
Microsoft’s .NET strategy is made up of
four types of components:
-
XML Web Services.
-
.NET client devices.
(Microsoft-based devices with the
“.NET Framework” client software
loaded, which can be Windows CE.NET,
Windows 2000, and Windows XP.)
-
Servers. (Windows
2000 Server, Windows Server 2003)
-
Development tools.
(Visual Studio.NET)
From an application
access and usage standpoint (i.e. the
purpose of this paper), applications
written for “.NET” have several
features, including:
-
Drag and drop
application deployment.
-
No application
conflicts (automatic side-by-side
DLL versioning, etc.).
-
No manual client
application installation.
-
Applications do not
need to modify the client registry.
How does .NET relate to
MetaFrame?
Based on the above key elements of
Citrix’s MetaFrame product and
Microsoft’s .NET strategy, it’s easy to
see that there are similarities between
the two.
Similarities between
Citrix MetaFrame and Microsoft .NET
Application Architectures
-
Client devices must
have client software installed in
order to access applications. (The
-
ICA client for
MetaFrame and the “.NET Framework”
for Microsoft .NET.)
-
Users can run new
applications simply by accessing a
URL.
-
Users can run
applications without manually
installing them on their client
devices.
-
The client software
works on many different types of
devices.
-
Both strategies
focus on “anytime, anywhere”
(ubiquitous) access to applications.
However, these
similarities are more coincidental than
planned. This comes from the fact that
both architectures are trying to solve
the same business problem (access to
applications). Citrix created an
ingenious “retrofit” solution that
provides ubiquitous access to legacy
Windows applications, and Microsoft
designed a new solution from scratch
that provides ubiquitous access to
future (i.e. .NET) Windows applications.
Primary Difference
between Citrix MetaFrame and Microsoft
.NET Applications
Citrix MetaFrame or
Microsoft .NET?
Given the fundamental
differences between MetaFrame and .NET
applications, we can begin to think
about how each solves (or doesn’t solve)
our business application access needs.
Advantages of MetaFrame
Applications
-
The client software
is smaller. (~4MB for the ICA client
vs. ~22MB for the .NET Framework)
-
Many client devices
and platforms are supported,
including non-Microsoft solutions
such as Java, UNIX, Linux, and Mac.
Disadvantages of
MetaFrame Applications
-
MetaFrame
applications execute in their own
silos. The only integration that
multiple applications have with each
other is “cut” and “paste.”
-
100% of application
execution occurs on the server, and
applications cannot be used if
connectivity to the server is lost.
When compared to Citrix
MetaFrame applications, Microsoft .NET
applications also have advantages and
disadvantages.
Advantages of .NET
Applications
-
They can be executed
from the device’s cache, without
connectivity to a server.
-
They can interact
with other web services and
applications.
-
Developers have a
lot of control over the screen. For
example, .NET applications can be
smart enough to display a different
user interface when running on a PDA
or a full computer.
Disadvantages of .NET
Applications
Looking out a few years,
it’s easy to think that the whole world
is moving towards “smart” XML–enabled
applications, and that MetaFrame (and
therefore Citrix) is doomed because it
focuses on legacy Windows applications.
However, this doesn’t necessarily have
to be the case.
The Evolution of
Citrix Server-Based Computing
Even though Citrix began
life as a company that provided remote
access to Windows applications, they are
looking forward to a bright future.
-
Citrix has a least a
few good years left with their
current MetaFrame architecture. Most
of the .NET development components
were not released by Microsoft until
2002. It will take a while for the
development community to begin
producing true .NET applications.
Also, true .NET applications require
substantial XML web services
infrastructure which will take some
time to put in place.
-
Citrix purchased an
XML web portal company called
Sequoia. Citrix is now beginning to
integrate true XML services into
their existing technology. This was
first be seen in their “NFuse Elite”
product portals—portals that will
drive the future of NFuse.
-
Citrix has perfected
the technology that allows
applications to execute in one
location while providing a user
interface in another location. There
will always be a need for this
technology, even in the .NET world.
-
Citrix applications
will continue to evolve, and the
Citrix middleware software will
become smart enough to know what
type of data is contained in the
applications that are executing. For
example, in today’s environment,
MetaFrame XP is very good at
allowing users to connect to
applications via the ICA protocol.
The ICA protocol allows users to see
the content of their applications,
but it doesn’t allow them to be able
to do anything with that content
(other than cutting and pasting it).
In the future, the ICA protocol will
be able to work with and understand
the data from ICA applications,
interfacing it with other portals,
users, systems, and XML web
services.
-
Citrix MetaFrame
will become more “.NET-ified,”
essentially becoming a .NET XML web
service. Citrix XML web services
will authenticate users and describe
what content is available. This will
allow for dynamic and ad-hoc
applications sets.
-
Citrix will continue
to develop their online and
real-time collaboration projects,
such as MetaFrame Collaboration
Server (“Project Pearl”) The need
for real-time integration will
always exist, and Citrix will be in
a great position to offer it.
Summary
Even though many people
believe that Citrix competes with
Microsoft in the “server-based
computing” arena (i.e. Citrix’s ICA
protocol versus Microsoft Terminal
Server’s RDP protocol), the future
“competition” will be between Citrix’s
server-based computing model and
Microsoft’s .NET application model. It’s
a forgone conclusion that Microsoft will
continue to develop RDP. Even today it
offers high resolution, shadowing, and
drive mapping. It will eventually offer
seamless windows and application
publishing. Since RDP will continue to
mature, Citrix’s “killer app”
functionality in the future will not be
its ICA protocol.
Citrix has publicly
stated that they are embracing .NET. The
question is not “whether” they will.
Rather, it’s “how” they will. Citrix and
Microsoft will continue to be strategic
partners—not competitors. Citrix
software will continue to provide users
with ubiquitous access to their
applications, content, and data well
into the future.