Introduction

InstallAware allows splitting the data contained inside a setup package into multiple online and offline parts. Web deployment traditionally involves putting the entire setup online, including the vital files that are always installed. This mandates an active web connection to install any part of the product. InstallAware sidesteps this artificial limitation and allows developers to precisely choose which parts of their setup are to be downloaded, and which are to be provided with the main setup program. Isolating runtimes and rarely used application features from the main setup download saves time and bandwidth for end users installing the applications, and also for companies hosting downloads. Application runtimes which may already be present on end user systems, and typically bloat setup downloads, are ideal candidates to benefit from WebAware Installations. With WebAware Installations, they will only be downloaded if required, and the main setup is wholly self-contained, capable of executing an installation without requiring an active Internet connection.

WebAware Installations (Partial Web Deployment)

A unique feature of InstallAware is the possibility of partial web deployment. With all other tools, setups that are web deployed reside entirely online. The end-user downloads a very small stub that contains only the setup driver. The stub then connects to the Internet and downloads the entire remainder of the setup from the Internet. This approach definitely saves time in some cases – for instance, the stubs don't download runtime components, such as the .NET runtime, if they are already installed on the end-user system. However, having to download the main application from the web as well, in addition to the runtimes, is an inconvenience at best. Even if the end-user system already has the required runtimes, the setup will still require and force an Internet connection.

The other alternative is to pack every runtime, along with the application itself, into a self extracting installer that contains everything. However, the downside to this approach is that while the setup is completely self-contained, and thus installs without requiring an Internet connection, it is bloated and may already contain runtimes that the end-user already has. Especially in the case of larger runtimes, such as the .NET runtime, this bloat can far exceed the size of the main application itself, and frustrate users in that they have to download and wait for what they already have on their system. InstallAware provides the perfect solution to this dilemma since its very first version: web media blocks technology.

Web Media Blocks

In InstallAware 7, setups are comprised of one or more web media blocks. A web media block is actually an MSIcode directive, very much like the compiler directives found in most programming languages. It tells the MSIcode compiler how the setup is to be split into multiple online and offline pieces.


When InstallAware 7 builds your setup, it parses your MSIcode and identifies which files belong inside which web media blocks. A web media block directive has effect from the point of its declaration in the script up to the next web media block directive. Each MSIcode command that requires source media, such as Install Files, becomes associated with the last declared web media block directive and the files for those commands are packaged into the web media block file defined by that directive, to be downloaded dynamically at runtime. You may declare an unlimited number of web media blocks in your MSIcode, and also use identical declarations more than once, in this way precisely describing the partial web deployment structure of your setup. At runtime, whenever an MSIcode statement that falls inside a web media block executes, the installation engine attempts to download that web media block (if it has not been previously downloaded). If none of the statements that require access to source media (such as Install Files) inside a particular web media block execute, that web media block will not be downloaded. The download process is resilient and has the capability to resume after an interruption. Moreover, if operating within a corporate environment where proxy servers are used, the download process automatically detects correct proxy settings and works seamlessly.

WebAware Installation technology, only available with InstallAware, provides flexible, partial web deployment capabilities for the first time in setup development history. You may place each separate application runtime inside its own web media block, therefore preventing bloating the size of your main setup executable. You may also use this facility to separate rarely used or space consuming features of your application from the main setup file. And any part of your setup which is inside an offline block goes directly inside the main setup file, helping you build a self contained installer that works without demanding an Internet connection.

Splitting your application into web media blocks will not only save your users undue frustration, but it will also result in significant bandwidth savings for your business. Because large runtimes and optional features will be downloaded only when absolutely required, your servers will conserve bandwidth up to levels not possible before.

InstallAware 7 improves web media block security by allowing each web media block to be individually encrypted with a separate key. InstallAware 7 also improves web media block resiliency, by keeping a full list of download URLs for each web media block, in case one (or more) URLs fail to respond.

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