Boot to the network via disk

I want to be able to boot to our network server to image computers using Norton Ghost images. I can get to the norton multicast server without a problem but I am trying to log on to the network so I can map a drive to the images and then do the transfer of the image drive to drive without having to use the multicast server. The only problem I am still encountering is logging on to the network woth the correct drive mappings. any Ideas will be welcome.

Thanks