My Organisation has a head office and 3 branches in different geological locations. Presently we have servers in each of thewse locations each hosting their own domain. I'm to implment a single domain architecture. We also have exhcnage servers (with POP3 connectors) in each location and require a single global Address List and access to new emails by domain users in any location. Is a VPN the right way? internet backbone is via Sattelite links with bandwdiths limited to 512Kb download and 256Kb upload. if VPN is the way, should it be hardware or software? What manufacturers are easy to configure and maintain? thanks in advance...
Hardware networking will almost always be a better solution than software networking. It could be done with just Windows 2003 cheaply, but it's slower and less flexible.
Cisco is the main business networking provider, and you can't go wrong with them for the best equipment. Not the cheapest, and not always the easiest to configure, but the most reliable and most powerful.
I've seen pretty decent results with SonicWall. Maybe a bit easier to configure and cheaper, but not as powerful as Cisco gear.