Virtual Private Networks are mainstays of remote security. Great efforts must be made to enable VPNs to accommodate increasingly demanding real-time IP-based applications.

This week, NetMotion Wireless said version 8 of its Mobility XE VPN, which is designed for Windows, now supports VoIP. TechWorld reports that packet-loss recovery, compression and othe techniques enable the VPN to work fast enough to support real-time applications. The VPN can switch calls between the wide-area network (WAN) and a Wi-Fi network.

NetMotion is not alone in making its VPN suitable for remote devices, of course. Late last month, for instance, Check Point Software said that its VPN-1 product supported the iPhone. InfoWorld reports that the VPN does this through the Apple device’s Layer 2 Transport Protocol (L2TP). No other software is needed, the story says.

This is a nice VoIP-News backgrounder on the overall issue of VoIP security, with a look at where VPNs fit in. VoIP calls are vulnerable during setup and as the data flows. VPNs are one option for shoring up these vulnerable spots. Gateway-to-gateway traffic is encrypted using the VPN’s built-in tools. This protection is automatic and extends to mobile devices. The writer does a good job of describing the overall state of VoIP security.

This Computerworld blog also looks at VoIP VPNs in a larger context. In this case, it’s a reaction to Avaya’s Unified Communications for Small Business family. The writer says a key advantage of this type of system in general (and the Avaya product in particular) is the ability to use home and cell phones as an extension in the office network. The writer notes that Avaya’s built-in VPN client automatically creates an encrypted link to the office. Many home routers have this capability, but it requires expertise that home users generally don’t have.

VoIP.com describes the challenges to using VoIP over a VPN in straightforward language. One problem facing all users — not just those seeking a VoIP connection — is that Network Address Translation (NAT) approaches used to extend the pool of available addresses and mask the corporate network make it difficult for the connection to be completed. The writer discusses how that hurdle is cleared. A problem that is more specific to VoIP and real-time protocols is that encryption requires the system to do more work and, for this reason, can stretch things to the point that quality is impacted.

Original source here.