Cisco supports VoIP over a VPN with new capability

Cisco Systems Inc. says its gear now supports voice and video over IP running through VPN tunnels, giving businesses the option of securing all types of traffic over a single link to a public IP network.

The new capability is called V3PN, pronounced V cubed PN. It relies on tagging voice and video packets with a high priority that gets them preferential treatment as they pass from one corporate site to another.

Because this quality of service must be maintained across the WAN link, businesses that want to take advantage of it must buy an IP WAN service from a provider with Cisco Powered Network multiservice certification. So far Sprint is the only announced provider with this certification.

Cisco says the VoIP over VPN technology will enable businesses to set up telecommuter offices with IP phones that have full corporate IP PBX functionality as well as a secure data link back to corporate network resources. Such offices would require a Cisco IP phone, a PC and a Cisco VPN router. Corporate sites would require a Cisco VPN gateway router and Call Manager IP PBX software.

To guarantee the low-latency that voice and video require, Cisco VPN gear will tag voice and video packets as high priority using type of service bits that are displayed as part of the IPSec header that is sent across the network. This type of service designation is then honored by all the Cisco network devices between the source and destination.

To be most useful, VoIP over a VPN would enable any employee to reach any other employee, such as two telecommuters. Cisco’s gear makes it possible for two such remote sites to set up a direct tunnel between them without going through a central hub, which could introduce too much delay to support voice and video.

The new capability also supports multicasting video.

Cisco also announced the availability of a new VPN gateway called the 7400 Router for corporate sites that can encrypt VPN traffic at 120M bit/sec with a VPN accelerator card. The device has no firewall, but a Cisco IOS firewall is available for it. The 7400 has options for dual RJ45 jacks for connecting to WAN links as well as 10/100 and Gigabit Ethernet ports. It costs US$18,500.