Hi Mike,
A couple of options can be explored here:
1. You can use a CVPN3002 Hardware client at the site where you have Sonicwall clients and connect to the VPN3000 using that.
2. Additionally you can use the machine which has the Sonicwall client to connect using Microsoft PPTP client which exists on all machines by default and has been confirmed/tested to work with the CVPN3000
3. If the Sonicwall low end device is capable of doing a Site-to-Site tunnel (like the 800 routers or PIX501's) , you can also try doing that.
These options donot include connecting the Sonicwall VPN client to the CVPN3000, as they are different vendor implementations and have not been tested to work.
Hope these options do help,
Let me know if you need any clarification,
Regards,
Aamir Waheed,
Cisco Systems, Inc.
CCIE#8933
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