Microsoft has witten a document on the subject topic which you can download from ftp://ftp.microsoft.com/bussys/winnt/winnt-docs/papers/. The document file is Dosclnt.exe. It address the following areas:
How to make a network installation startup disk.
How to make an installation disk set and run Setup.
How to modify the startup disk for NWLink frame types.
How to modify the startup disk network adapters that are not in the list.
Additional TCP/IP settings for the Microsoft Network Client for MS-DOS.
I quote from the Overview:
The Microsoft Windows NT Network Client Administrator tool allows you to create a network installation startup disk. This startup disk allows a computer to start from a floppy disk that contains the basic MS-DOS system files with networking. This allows for an "over-the-network" installation of operating systems on computers that do not currently have an operating system or networking ability.