Application developers are leveraging Ajax to deliver the next generation of Web applications. In this white paper learn:

• What Ajax is (and isn't)
• How Ajax applications differ from traditional web applications
• How Citrix NetScaler can increase the performance of Ajax applications while reduce the cost of hosting Ajax applications
  
  
  
  

I am sure you all must have heard about the GeekSpeak Live event during synergy. Barry Flanagan and I are also doing GeekSpeak BarCamp on Wednesday May, 21st.

The goal for this is to give the technical audience at Synergy a chance to get together to discuss technical content most interests you. No marketing slides, no features and benefits, just hard core technical discussions about any IT topic that interests you and the attendees. You can run a white board discussion, present a technical presentation on your latest project, or show a demo of your newest creation with an SDK. Anyone can sign up for a slot. You may be an IT admin, a technology consultant, a Citrix technical employee, a technical employee of a Citrix partner (or competitor), or a student who loves technology and wants to share it.

We have 12 slots filled up so far. Read Barry's Blogs for more info here and here.

If you want to sign up then please comment on my blog or go directly to the GeekSpeak BarCamp page or comment on this blog.

Are you planning to attend the GeekSpeak Live and the GeekSpeak BarCamp?	Choose
Won't miss it for anything. Looking forward to meet all the geeks
No. I will miss all the fun

Klaus Oestermann,VP of the Application Networking Group at Citrix, did an short interview with Aving.net at INTEROP Las Vegas about the new Citrix NetScaler MPX.
.

Check out the NetScaler MPX live demos at Citrix Synergy.

We now have twelve of the twenty sessions at the Geek Speak BarCamp filled (read background on Geek Speak BarCamp here, here and here).

1. Virtualization Defined - Joe Shonk

2. The Stress of IT - Jim Kenzig

3. Virtualization Oriented Architecture over VDI - Jaymes Davis

4. What is High Availability - Michael Bilancieri

5. Ultra Mobile Gadget Tech - Adam Marano

6. HP Print Drivers in a Citrix Environment - Robert Tuft

7. Citrix WorkFlow Studio Examples - Vishal Ganeriwala

8. Fifteen Years with Citrix - Steve Greenberg

9. Web Interface Internals - Jason Conger

10. Provisioning Best Practices - Pete Downing

11. Performance Matters on the Edge - Tim Mackey

12. Server Virtualization Best Practices - Peter Blum

Geek Speak BarCamp has twelve tech sessions so far to go along with the nine industry experts speaking at GeekSpeak Live. There is also the long list of technical sessions in the iForum and Application Delivery tracks.

We are still working to fill the final eight slots. Please submit your session topic now. You can use the comments in this thread, or you can email me at citrixblogger @citrix.com . You can also IM questions to citrixblogger on MSN, Yahoo and Google Talk.

If you have not yet registered for Synergy, you can click here to to complete your registration. I look forward to seeing you at Synergy and the Geek Speak BarCamp.

Policies are used to configure various Citrix NetScaler Application Switch features. For example, the parameters for compressing content are defined in a compression policy.

The features that use policies are:

• Load Balancing
• Content Switching
• Content Filtering
• AppCompress
• Cache Redirection
• SSL VPN
• Priority Queuing
• DoS Protection
• Sure Connect

Policy expressions are applied to content that enters the switch. Expressions are shared among features, but actions are feature-specific. For example, you can create an expression to identify .pdf files being sent through the system. You can then create a compression policy that uses this expression to compress those files. The Policy Engine (PE) refers to the architecture in the Citrix NetScaler Application Switch for versions up to 8.x. The architecture for Policy Engine and the manner in which it operates is presented in this Deployment Guide.  Did you know that each feature in the Citrix NetScaler Application Switch is processed in a certain order, and the Policy Engine (PE) applies policy according to that order.  That order is represented in this diagram and discussed in the Deployment Guide for Policy Engine (PE).

Watch this Policy Engine Tip:

Tap into the power of AppExpert!

As web applications grow in complexity, the art of accelerating them seems to remain the same. This art is performed by applying some basic concepts to the application; that is, Caching, Compression, Load Balancing, Global Server Load Balancing, SSL Offload & Acceleration, Content Switching, TCP Multiplexing and SSL Session Reuse.

Citrix® is a leader in Gartners magic quadrant for Application Delivery with their flagship appliance NetScaler®. NetScaler accelerates web application performance by leveraging multiple acceleration technologies and innovative TCP optimizations.

Whether you are building out a new datacenter and architecting it the right way, or retrofitting an existing datacenter, Citrix NetScaler will perform and keep costs down. Whether you are looking to accelerate legacy enterprise applications such as Oracle or SAP, or building a new web 2.0 social community, Citrix NetScaler contains all of the tools to get you there.

Citrix NetScaler web application delivery solutions are purpose built appliances that accelerate application performance, while simultaneously reducing datacenter costs and improving web application security. Platforms range from the entry level 7000 to the latest MPX-series appliances that provide an industry-leading 15 Gbs of throughput at Layers 4 through 7.

There's more here: Case Studies, White Papers, Analysts , Datasheets

Check out the new MPX!

Buy it here!

Tap into the power of AppExpert!

I'm sure many people are wondering why Citrix creates a quirky communication solution called EasyCall. Why does communication have to do with Citrix's core business?

The answer is: SIMPLICITY!

We all know how convenient it is to make phone calls from your cell phone. All you need to do is look up someone's name and hit dial. However, why is it that you cannot do the same with your PC? Your PC is arguable your most comprehensive and most powerful phone book in your possession.

And today, you are seeing more and more software and web applications that have chat and voice capabilities built into them. Just in the last few years, instant messaging clients from Yahoo, Microsoft, AOL, etc have all embedded voice capability inside.  

 
You are also seeing an evolution led by Microsoft, Adobe, IBM, etc to add communication as just another feature within the applications. A good example is what you see below with Microsoft Outlook, you can simply click on the Smart Tag feature and call someone. Or from Adobe where its Acrobat includes a web collaboration feature. None of these communication capabilities are what you would traditionally associate with the software companies. Yet, these features are being introduced more and more by the software companies.

This is because for an average office worker, it is much easier to learn a simple new feature within the existing application than to learn an all new softphone interface that sits outside of that work environment. Softphone adds complexity to the user environment and has demonstrated a profound negative impact on its adoption rate. Softphone also introduces unnecessary challenges to the already stretched IT organization.

Since Citrix today can deliver thousands of business critical applications to the users, we simply add voice communication on top of those delivered applications. You can now call anyone from any applications without having to do any sort of integration work! This simple addition brings great values to the customers. This is why EasyCall is an integral part of the Citrix solution.

So check out EasyCall today here.

I think this is the most useful post ever for Citrix admins!

Seriously it has always been hard for me to find where and what are the latest hotfixes for the Citrix products... but this picture has changed.

With the new revision of Citrix's Support site (support.citrix.com), now it's easier to find  the latest fixes and patchs for your Citrix products.

Here's the list:

Presentation Server 4.5 for Windows Server 2003 - x86

Presentation Server 4.5 for Windows Server 2003 - x64

Presentation Server 4.0 for Windows Server 2003 - x86

Presentation Server 4.0 for Windows Server 2000 - x86

Access Gateway 4.5 Advanced Edition

Access Gateway 4.5 Standard Edition

Access Gateway 8.0 Enterprise Edition

Provisioning Server 4.5

Citrix NetScaler 8.0

Citrix NetScaler 7.0

Citrix WANScaler 4.x


Select the products you have, subcribe to its RSS feed and stay in-sync with all later patches and fixes for it.
This is wicked useful!

Cheers,
Gus Pinto

I have taken all the posts in the series that I released on the Citrix Workflow Studio Partner Tech Preview, and have incorporated them into a single document.

After receiving many requests from people to make the entire series of articles available as a downloadable document, how could I not make one available.

So here it is by popular demand, enjoy!

Download: Introducing Citrix Workflow Studio - The Complete Introduction
 

Citrix AppExpert  is an online community dedicated to NetScaler users. This moderated community is the best place for conversations on how to get the most from your NetScaler deployment, including creative AppExpert policies, innovative configurations, integration with other infrastructure technologies and more

AppExpert represents a breakthrough in ease-of-use, developers occasionally need more programmatic ways to invoke policies or system settings as well. For these scenarios, AppExpert also provides powerful APIs that use industry-standard WSDL (web services description language). Using AppExpert APIs, external applications and systems can automatically modify any NetScaler system setting and any AppExpert policy.

Continue to the AppExpert Community

Learn hands down how to implement Citrix XenApp with NetScaler.

Here's a paper that can show you how.

Download

Becoming an Application Expert means that you can profile an application and quickly determine how it can be architected or re-constructed for higher performance. Of course, we want you to use the Citrix Application Switch as part of the architecture. In Part 1, we learned how to profile an application to learn what it looks like as the traffic flows through the Citrix Application Switch. Now we will determine what parts of an application are cacheable and what parts are non-cacheable.

By Application Profiling we can determine which parts of the application are cacheable and non-cacheable just by looking at the Request and Response headers. The application will sometimes tell you through it's "Cache-Control" header directives. Some content that we just know is static and doesn't ever change, we can consider cacheable as static content. Content that changes, such as reports, are often considered non-cacheable but with the help of Selectors and Dynamic Content Groups in the Citrix NetScaler, this content can be cached. As a proof of concept, we deployed the Citrix NetScaler Application Switch in the front of Oracle E-Business Suite v12 application and implemented caching policies for both static and dynamic content. As it turns out, alot of static content is cached by default policies and setting up dynamic policies is not that difficult. To see how, read the Caching Deployment Guide for Oracle E-Business Suite v12.

Watch this Caching Tip:

Tap into the power of AppExpert!

The recent announcement about the new Citrix NetScaler MPXhas been getting great blogosphere buzz

Michael Vizard of the Masked Intentions blog at eWeek had this to say -

Read the rest of the post here.

Sean Michael Kerner of Internet News is also impressed with the NetScaler MPX. He writes on his blog -

Kerner goes on to ask ...

The Application Delivery Network blog had this to say -

Two concerns this bloggers has are highlighted in the post -

Price - "The downside? Price, of course. It's always about price in this market."

And that other software company that does virtualization - "For this to be a really major win for Citrix it needs to expand and include VMWare as an option "

This is the money quote however -

You can get more info on the NetScaler MPX at the product page. Of course, you can see the NetScaler MPX at Citrix Synergy.

If you have missed these presentations and videos from CSEIT 2007 then take a look at them. These presentation are really technical and given mostly by Citrix escalation engineers.

http://support.citrix.com/article/ctx115136

To view the CSEIT presentations and webcast recordings from the Citrix Presentation Server and Citrix NetScaler sessions, please click the appropriate presentation title.

Note: A codec may be necessary to view some of the presentations. The codec is available at http://www.gotomeeting.com/codec.

Citrix Presentation Server

• CTX115207 - CSEIT 2007 - Printer Driver Management

• CTX115208 - CSEIT 2007 - Citrix Presentation Server Health Monitoring

• CTX115192 - CSEIT 2007 - Troubleshooting Tools for a Citrix Presentation Server Environment

• CTX115204 - CSEIT 2007 - Understanding and Troubleshooting the Application Streaming in Citrix Presentation Server 4.5

• CTX115202 - CSEIT 2007 - Brief Troubleshooting Guide

• CTX115225 - CSEIT 2007 - Citrix MFCOM Programming for Administrators

• CTX115228 - CSEIT 2007 - Using and Understanding Citrix EdgeSight 4.5

• CTX115206 - CSEIT 2007 - Citrix Presentation Server 4.5 / Feature Pack 1

Citrix NetScaler

• CTX115222 - CSEIT 2007 - NetScaler Architecture, Concepts and Networking

• CTX115226 - CSEIT 2007 - Monitoring the Citrix NetScaler Application Switch

• CTX115221 - CSEIT 2007 - Command Center 3.0

• CTX115227 - CSEIT 2007 - Printer Driver Management

Citrix® NetScaler® web application delivery solutions are purpose built appliances that accelerate application performance up to five times, while simultaneously reducing datacenter costs and improving web application security. Platforms range from the entry level 7000 to the latest MPX-series appliances that provide an industry-leading 15 gigabits per second of througput at both Layer 4 and Layer 7 with maximum simultaneous use of all functional modules. They provide visibility into the end-user application experience and comprehensive web application security in concert with advanced traffic management. NetScaler, a member of the Citrix Delivery Center product family, is an ideal network management solution for any enterprise seeking accelerated Web application performance, improved web application security and increased application availability.

Continue at Source: Citrix

*Santa Clara, CA » 4/28/2008 »* Citrix Systems, Inc. (Nasdaq: CTXS), the global leader in application delivery infrastructure, today announced its new NetScaler MPX line of web application delivery systems.  The new NetScaler solutions feature a massively parallel multi-core system architecture that significantly increases datacenter capacity and delivers 2.5¹  times more web applications with the same infrastructure footprint. Citrix® NetScaler® MPX also provides unmatched performance when delivering applications that demand the highest security and best end-user experience. Today's web applications are straining traditional load balancers and rigidly-constructed datacenters with the integration of rich media capabilities, service oriented architectures (SOA) and interactive Web 2.0 capabilities. These applications are significantly more complex and resource intensive, yet they must still be delivered with the fastest performance, best security and lowest cost. NetScaler MPX is the industry's first web application delivery controller to drive greater than ten gigabits per second (Gbps) of real world application performance while concurrently providing advanced acceleration, traffic compression, and integrated web application firewall security - all in an energy-smart appliance form factor.

As an integral component of the Citrix Delivery Center^TM product family, NetScaler MPX also enables the push toward dynamic datacenters that can more easily adapt to the needs of today's increasingly complex web applications.  As part of this end-to-end solution architecture, NetScaler MPX provides sophisticated workflow virtualization that senses changes in application demand and automatically invokes the necessary application and server resources to meet dynamic workloads. This unique capability provides a fundamental building block of the new dynamic datacenter by offering the necessary scalability and virtualization capabilities needed to cost effectively deliver both enterprise and Internet-facing web applications.

"With its high-performance architecture, NetScaler MPX relieves key customer pain points in large, dynamic datacenters, including the challenge of reducing power consumption while managing traffic loads that are beginning to cross the 10 Gbps threshold," said Cindy Borovick, Research Vice President for IDC's Datacenter Networks service.

Continue at Source: Citrix

This is my first blog entry in this new AppExpert Community site.

I am excited that we are now ready to tap into the power of the community to spread the
knowledge power of AppExpert amongst the user base of Citrix application networking products!

The first thing I would like to share is my core belief in the strength of AppExpert Policy system,
which is its ability to provide powerful, extensive, flexible and expressive policy control while keeping
the simple tasks extremely simple.

AppExpert blends the power of extremely advanced application layer policy control with the ease of point and
click ease of use in its declarative rule setting model.  Also, while administrators can compose
very complex expressions and combine them into powerful predicates and rule sequences,
AppExpert does not forget to keep simple things simple - rules that are needed most often are
often just a click or two away!

 This is in keeping with my often expressed analogy of Digital SLR camera model of admin interfaces.
(yes, my esteemed colleagues are indeed quite sick of hearing me expound on this analogy, but I will do so
here for this new audience! )

Even the most complex Digital SLR cameras come with a fully automatic "A" mode for point-and-shoot
simplicity, while presenting an "PA" mode for  more advanced users who want to customize only a couple of
key settings and a fully custom "M" (manual) mode for full power and control of all the aperture, speed,
Lens, focus etc settings of the camera.

AppExpert similarly, makes it a quite simple click for simple content switching type rules.  But it goes on to
provide full power  of pattern matching, predicates and rule sequences, for the more advanced users.

Granted it does not provide the "M" mode of a "Turing-complete" programming language or custom
script exits - yet.    The reason, is that Citrix architects have wanted to first natively provide
the advanced capabilities in the PA mode, rather than just punting
the task of key application layer policy rules to be programmed in scripting languages by the administrator
without first carefully understanding the customer requirements.

Other systems have jumped to "outsource" development of such policy capabilities to their users,
thus subjecting them to the rigors of hiring programming and scripting experts even for simple
app layer rules!  And, sometimes they claim to provide a grab bag of such scripts on web-sites to
copy and paste for their use.  That's great, but have they stopped to think if that's the way someone
can set up rules for their system without a scripting expert, what happens when something breaks in that
script or it is not 100% suited to their specific installation?  Who troubleshoots when things go bump
in the middle of the night or user traffic shoots up on a popular web2.0 application and the script breaks?!
Further, most often such scripting system provide a level of performance that is an order of magnitude
slower than the native rules.  So while tempting with complete freedom, these scripting environments
very often flatter to deceive, and are unsuitable for many demanding, high throughput applications.

Citrix architects have taken the approach of providing the best of both worlds by providing
powerful capabilities within the native AppExpert system so that even very demanding
policies can be set using the visual, declarative point and click paradigm.  And, these rules execute
at the speed of the core switching engine, preserving the high throughputs.  This means that
customers can achieve what they need with the robustness and speed and express it with the
ease of visual+declarative interface and leave it to the system to carry out their wish in the fastest
possible way.  The engine keeps getting optimized, so they continue to get performance improvements
as well, completely transparently.  With a script, they have to reprogram, retest, and suffer through
a new test of hard to troubleshoot corner case bugs!

But does that mean that AppExpert will never ever offer the M mode?  To the contrary.
Long time  users of AppExpert will note that it has consistently evolved
release after release to include more powerful features and more flexible capabilities.
This will continue and AppExpert will add more flexible and extensible policycapabilities.

Moreover, the Citrix architects are carefully examining a structured way
to allow customers to leverage their investments in gateway logic to be applied to customize
policy processing.  You all will hear more about it as the plans get more concrete and closer to
fruition.

Watch this space for exciting AppExpert improvements in an Citrix app networking system near you!

Prabakar Sundarrajan
CTO, Application Networking Group,
Citrix Systems, Inc
 

Application Profiling

Introduction:

I can turn you into an Application expert in 5 minutes by reading this post.  Just do what the experts do, or even the not-so-experts.  They pay meticulous attention to the requests from clients and the responses from servers, both headers and body content.  You do this the old fashioned way by taking a trace.  There are better tools out there, some free, some not-so-free.

Running a trace:

Running a trace will help you 'profile' the application. It is recommended that you do this before placing the Citrix Application Switch in-line of the Application traffic. This will gather important information about the Application that will help you understand it's basic operation at Layer 7, and help you begin to understand what it is that needs to be accelerated - cached, compressed, load balanced, ssl offloaded, etc.

Running a trace exposes the flow of transactions between all points of interest. Traces are especially helpful when digging in to find what is contained within the headers being exchanged between the client and the application.

Taking a trace with wireshark:

The free network protocol analyzer called wireshark, http://www.wireshark.org, will capture packets for you on the localhost, whether it's windows or linux. By filtering the stream of packets by IP Address, right clicking and selecting 'Follow TCP Stream' inside of wireshark, you can see the headers for both requests and responses.

Wireshark tip 1 Find the first 'SYN' in the stream, right click, 'Follow TCP Stream'.

Wireshark tip 2 Client requests are in Red, Server responses are in Blue.

Taking a trace with the Citrix Application Switch:

If the Citrix Application Switch is already in place, a trace can be run directly on the Citrix Application Switch. Running a trace will expose the flow of transactions between all points of interest, especially the client, load balancing VIPs and backend servers. Traces are especially helpful when digging in to find out if the proper headers are being exchanged between client & VIP and VIP & backend servers. A trace can be run directly on the Citrix Application Switch. Once downloaded this file can be opened and request and response headers read with Wireshark, a free network trace utility, http://www.wireshark.org. From the Citrix Application Switch GUI, navigate to NetScaler -> System -> Diagnostics -> New Trace -> Run. 

Viewing headers with Paros:

Paros was originially written for web security, but has value when viewing request and response headers, cookies and the like. Through Paros's proxy nature, all HTTP and HTTPS data between server and client, including cookies and form fields, can be intercepted. There is an additional option of trapping and modifying data before sending it on to the server, or client. Paros can be found at http://parosproxy.org. Free.

Viewing headers with Live HTTP Headers:

Live HTTP Headers, http://livehttpheaders.mozdev.org/, was developed for use with the Firefox web browser. It is a free add-on and allows you to view HTTP header information in real time. Free.

Viewing headers with IE Analyzer:

IEInspector HTTP Analyzer, http://www.ieinspector.com, is a tool that allows you to monitor, trace, debug and analyze HTTP/HTTPS traffic in real-time. It works with Microsoft Internet Explorer. Not-Free.

Viewing headers with IE Watch:

IEWatch, http://www.iewatch.com, is another plug-in for Microsoft Internet Explorer that helps you profile your web applications. You can use this tool to dig deep into the inner workings of web applications to find hidden issues. Not-Free.

Watch this Application Profiling Tip:

Tap into the power of AppExpert

The SAP Enterprise Service Oriented Architecture (SOA) provides a blueprint for services-based, enterprise scale business solutions that are adaptable, flexible, and open. Enterprise Services Architecture takes the concept of service-oriented architecture to a new level by transforming Web services into enterprise services. Bringing Citrix and SAP Enterprise Services Architecture together reduces the dependence on customized applications, and increases flexibility and reduces time to deployment while reducing operational expenses.

Watch this Load Balancing Tip:

Tap into the power of AppExpert

If you are a Web developer or an IT administrator then AppFirewall feature of NetScaler can give you sound sleep at night and save you from some redundant implementation security within each application. Application Firewall by default provides following security features

• Start URL check. Examines the URLs to which incoming requests are directed, and blocks connections to URLs that are not listed in the Start URLs list, or that a user has not reached by navigating to them from listed start URLs.

• Cookie Consistency check. Examines cookies returned with user requests to see that they match the cookies your web servervset for that user. If a modified cookie is found, the cookie is stripped from the request before the request is forwarded to the web server.

• Form Field Consistency check. Examines the structure of the web forms returned by users to your web server, and verifies that the structure of the web form and any default data are unchanged.

• Buffer Overflow check. Examines requests to detect attempts to cause a buffer overflow on the web server.

• Field Formats check. Examines the data a user returns using a web form on your web site and verifies that the data being returned for each field is valid for that field.

• Deny URL check. Examines the URLs to which requests are directed, and blocks connections to all URLs specified in this list.

• Cross-Site Scripting check. Examines requests and responses for scripts that attempt to access or modify content on a different web site than the web site where the script is located. When it finds such a script, it either renders the script harmless before forwarding it to its destination, or blocks
  the connection.

• SQL Injection check. Examines requests that contain form field data for attempts to inject SQL commands into a back-end SQL database, and when it detects injected SQL code, either renders the injected SQL code harmless before forwarding it to the web server, or blocks the request.

• Credit Card check. Examines web server responses, including headers, for credit card numbers. If it finds a credit card number in a response, it either removes the credit card number from the response before sending it, or blocks the response.

• Safe Object check. Allows you to create classes of protected content, such as social security numbers, and protects them in much the same manner as it does credit cards.