Supercomm: Net.com better secures VoIP nets

Net.com announced at Supercomm Tuesday that its Shout voice-over-IP call gateways now come with a firewall that blocks anything that is not a voice call to better secure networks that support VoIP.

With this blocking, the device stands between public and private IP networks and can help prevent attacks on call servers from outside corporate networks. Shout gear can be used to connect traditional IP phones in offices to IP networks and handle the necessary signaling and media conversions among protocols.

The device is typically connected outside a firewall, so blocking non-voice traffic is key to securing the link to the outside network.

The new feature is part of the version 3.5 software upgrade for the box to be released in September. Another feature of the software will add the ability to pass Session Initiation Protocol traffic and voice calls through corporate firewalls. Many legacy firewalls do not handle SIP and IP calls well because the firewalls change IP addresses on outbound traffic from private to public. Unless this is resolved, the traffic can be dropped when source IP addresses are checked.

The new software will support a back-to-back agent that translates the IP addresses and keeps track of them so the return flow of phone calls can reach the telephones they are supposed to.

Net.com is also introducing support for maintaining IP QoS as traffic is handed off to ATM networks, via net.com's Scream broadband remote access servers that support DSL services. Many providers carry data to their DSL customers as ATM, and customers typically plug into their DSL routers using Ethernet.

Service providers that want to offer multiple levels of QoS to DSL customers need a way to maintain that quality as it crosses the ATM portion of their access networks on a single ATM virtual circuit. The Scream device sits between DSL access servers and carrier IP networks, receiving customer traffic as ATM and dropping it onto IP cores. The implementation complies with the suggested standard from the DSL Forum called TR 59.