Hello,
A customer is asking me if there is a way to use low-cost SIP ATA's such as the PAP2 to register on a CUCM via the Internet without a VPN tunnel. Obviously we can make these boxes work directly with the CUCM on the LAN or via a VPN but the customer would like to deploy this like an ITSP would - SIP registration to a public IP address that would connect it to the CUCM.
To me, this is SBC-like functionality... the customer already has CUBE for SIP Trunking but I'm not sure how to approach this on the SIP client side. Is there a way to do this using the customer's current infrastructure (CUCM 8.5.1, CUBE on ISR running IOS 15.1.4(M5), multiple static IP's on a fiber connection)? Security is not really a concern as it is for for temporary deployments only. If SRTP works then it's a bonus.
Thanks