There are several methods, depending on the level of redundancy you want, the amount of data you want going across the NW, how much the files change, and where the restore point is.
If you want to do a daily backup, then I would recommend using RoboCopy. This can be set as a scheduled task, and one benefit is that if you use the /XO option, it will only copy changed / new files, reducing the traffic & copy volume.
If you want something more real-time, then I would suggest using DFS & setting up replication.
http://www.windowsnetworking.com/articles_tutorials/Configuring-Using-DFS-Replication.html
http://technet.microsoft.com/en-us/library/bb727150.aspx