I've attached configurations for a UC520 phone system and Cisco ASA 5510 firewall where the system is colo'd at a data center and no users connect directly to the phone system over the LAN.
- The Cisco UC520 phone system sits in a data center with a 10Mbps Internet feed.
- All users on this phone system are remote users connecting with Cisco IP Communicators and Cisco SPA-525G phones.
- Every user on the system connects their PC, laptop, or SPA525G phone by first initiating an SSL VPN connection. The SSL VPN sessions terminate on a Cisco ASA 5510 firewall
- The Cisco ASA 5510 firewall was used to terminate SSL VPN sessions to get around the limit of 10 VPN tunnels on the UC520. Purchased a 25-user SSL VPN license for the ASA.
- No users are located at the data center where the system resides.
I have this problem too.