Question : Problem: Setting up a Cisco 851 for (at home) software to (at office) router VPN access

I have a recently purchased Cisco 851.  The main purpose of this router is to be able to VPN into the unit from home.  The 851 is located at the office off a static IP of 71.158.200.xxx.  I am looking for the easiest way to setup the unit and find software that will allow me to connect to the device and how to go about all of that.  Thank you.

Answer : Problem: Setting up a Cisco 851 for (at home) software to (at office) router VPN access

You are going to enter a group name and password (preshared key) which is what you will enter in the VPN client connection information.  You will also specify XAUTH usernames and passwords for per-user authentication and define a pool of addresses the VPN clients will receive (make sure the pool is a different subnet from your home and office networks).  It should also give you the option of using NAT-T (NAT Traversal) which you want to use and whether you want to split tunnel or not (only send office destined traffic over the VPN).  You can also define the level of encryption and hashing algorithm (3DES, SHA).  Hopefully the wizard fills in the rest and is intuitive (I've never used it).