Just months after announcing a partnership with Asterisk maker Digium, Ranch Networks has solidified that relationship by rolling out a line of appliances to make Asterisk more redundant and improve uptime.
Morganville, N.J.-based Ranch Networks yesterday announced that it was adding 1+1 High Availability (HA) to its RN line of appliances. The 1+1 HA feature gives users redundant and uninterrupted VoIP service between any two Asterisk servers, even when the servers are not on the same network. If a server fails or shuts down, the RN box switches all VoIP service to the second server. Asterisk is a widely known and popular open source IP PBX.
The RN appliance connects two Asterisk servers and monitors each by simulating real-time Session Initiation Protocol (SIP) registration requests. If a server stops responding to those SIP requests or indicates a problem, the RN automatically and seamlessly redirects calls to the other server without VoIP service interruptions.
"If an Asterisk server is not available, or as soon as there's a link failover, it will switch to the standby server," said Ranch Networks founder and CEO Ram Ayyakad.
The 1+1 HA feature synchronizes the two Asterisk servers by representing them as a single IP address, which allows IT to maintain or replace an Asterisk server without losing VoIP service and without interruption to that service.
Ranch Networks has four RN appliances to choose from, depending on Asterisk deployment size and the number of simultaneous calls the Asterisk servers need to support. The RN300 is for smaller deployments, while the enterprise model, the RN40, can handle roughly 400 concurrent calls. There are also two others.
IT can also manually configure the RN appliances to automatically kick service over to the standby Asterisk server, based on specific criteria. For example, managers can configure the box to switch service if the response to the SIP registration request is too slow or if the response is slow for five consecutive requests, Ayyakad said.
"It is monitoring the Asterisk server's health based on SIP," he said, "to make sure it is available and all of its services are running."
Essentially, Ranch Networks' technology sends instructions to the firewall to open the ports on an as-needed basis. Media streams can flow from one phone to another, then close ports when the call is terminated.
Instructions are also sent to the appliance to determine the amount of bandwidth needed. As calls come in, data is shrunk down to allow necessary bandwidth on a protocol basis, giving voice priority. The appliance can support multiple phones behind any number of firewalls.
At the time of that announcement, Digium president and Asterisk creator Mark Spencer said security had become an issue for SIP deployments because ports need to remain open at all times to facilitate voice traffic. But open ports could act as open doors for potential intruders, he said.
"In providing this technology, we are proactively addressing the security of VoIP before it becomes a major concern," Spencer said, "while also providing quality of service and increased scalability."