Here is a brief introduction on the deployment service in Windows Server 2008:
Generally speaking, we can divide the deployment processes into two parts, generating an image and installing the image.
How to generate an image:
You can manually create an image (either syspreped image or images from the Setup media) that you want to deploy to computers, including some drivers, applications, packages and unattend answer file. You can use some tools such as imagex and pkgmgr (included in Windows AIK) to modify the image.
If you think that modification of the image is much complicated, well, you can try the BDD 2007. It helps you generate an image automatically, associating the image with drivers, applications, packages and so on.
How to install the image:
Of course, you can install an operating system directly from the Setup media.
Or, after generating the image (including the boot image and the install image), in whatever way, you can burn it into a DVD media and then use this DVD to install the operating system onto computers.
If you want to deploy the operating system through the network, you can use one of three methods:
1. You can use BDD 2007. However, you may also need to burn the boot image (Windows PE) onto a DVD media and use this DVD to install the operating system.
2. If you use WDS server, you can install the operating system thoroughly through the network without any DVD or removable media.
3. You can also manually deploy the install image by using some command-line tools including in Windows AIK. However, this is not easy to do.
So, Windows AIK provides a lot of tools, such as imagex and pkgmgr, to help you modify the image (boot image and install image) and create unattended answer files. BDD 2007 helps you generate an image automatically, if you think that manually modifying an image is a complicated work.
If you want to deploy an image and if you are in an Active Directory domain environment, I would like to suggest that you use WDS, as it has some advantages than BDD, such as WDS cooperates with Active Directory and you can apply some policies to restrict the deployment processes.
For more detailed information, you may need to read these articles:
WDS step by step guide – http://technet2.microsoft.com/windowsserver2008/en/library/7d837d88-6d8e-420c-b68f-a5b4baeb52481033.mspx?mfr=true