Deploying Image at remote site using image located at site

Hi,

I'm trying to deploy an image to a remote site. The deployment server is at our head office, the image file it's self is located on a machine at the remote site, the plan being that the data would not have to be transferred across the WAN during deployment. However I am getting very slow transfer speeds and it seems as though the data is being sent from the remote site across the WAN to the deployment server and then back across the WAN to the machine where the image is being deployed. Does anyone have any way to avoid this? Do I have to install a deployment server at the remote site? If I do need to would this mean I need to buy another Snap Deploy server license?

thanks

Jon