NATAssistant
NatAssistant is a product developed by Comstock Innovations Group that enables users of Dialogic's HMP software to traverse NATs and firewalls. By intercepting SIP packets generated by HMP locally, NatAssistant is able to correct relevant port and ip address information before it is sent out over the internet. By doing so, the remote party is able to correctly establish audio with the HMP software across the NAT.
Many users and developers would prefer to leave HMP behind a NAT for security reasons. Regretably, until NatAssistant, they were forced to place a computer on the open internet with a public IP address.
Problem
When a SIP based call is initiated, critical information about the call, such as the ip address and port for the RTP datastream, needs to be revealed to the called party.
Unfortunately, when the HMP software sits behind a NAT or firewall, HMP is only aware of it's local LAN's ip address, and not its public IP address, which is critical information needed by the called party.
Accordingly, when HMP tries to send the call related information to the called party, it incorrecly uses it's local LAN address. Since the called party has no notion of the local lan address, it cannot send RTP (voice) traffic back to HMP.
Solution
NatAssistant intercepts the SIP packets generated by HMP. It makes appropriate corrections to the SIP message and then transmits the corrected packet to the called party.
This allows the remote caller to establish it's data stream with HMP!
NAT Assistant Quick Info
Latest Release: 1.3
Price: $395.00 USD
Yearly Support: $100 USD
Includes Free Updates