VPN on wIn 2K Proff

WE have VPN configured between our company & our customer using Cisco PIX 506 FIREWALL. we have created a IPSEC tunnel & the encryption used is 3DES. we are able to access our customers LAN using this tunnel. am using the Pre-Shared key Authentication method

now can i create the same tunnel without using CISCO PIX 506 firewall & just by using the VPN, IPSEC & 3DES support given in Win 2K proff. i’ll configure this settings with the pre-shared key on win2k machine.

How far will this work ? do u have any valuble input for me in configuring vpn on WIN 2k ?