This promise is largely an artifact of what both companies are bringing to the table.
As Phil Hochmuth of Network World notes, Vyatta makes the Open Flexible Router platform, an open source, Linux-based enterprise WAN router, which uses the eXtensible Open Routing Platform (XORP) software stack. Open source firewall and VPN technology are also in the package. Digium develops the popular Asterisk open source VoIP platform, a Linux-based IP PBX, voicemail and telecom server, used widely in education, government and private enterprise.
The alliance has not yet spawned any publicly revealed products. Still, progress can be seen in the current initiative to integrate Vyatta's router and Digium's IP PBX.
"Later this year, users could expect to see a unified platform that could deliver, WAN connectivity, security, remote access and VoIP services, features and applications in one nice, neat open source package," Phil writes. (An all-in-one appliance is not much of a stretch to consider, since both vendors currently offer their code pre-loaded onto hardware.)
I agree with Phil that such a mashup could be a competitive threat to far-more-expensive proprietary solutions from Cisco, Nortel, and a combined Juniper-Avaya solution. While savings would vary by solution and installation, Vyatta claims as much as a 90% cost savings over their proprietary solution rivals.