With a focus on building virtualization into advanced data centers, the network industry will convene at its largest trade show this week in Las Vegas.

Nortel, Cisco, Foundry Networks and Avocent are set to detail enhanced data center products and directions, while such companies as Citrix Systems and Polycom will enhance security, application acceleration, videoconferencing and security wares.

The show kicks off amid a conflicting economic backdrop. While many vendors are having good financial years, others such as Cisco, Extreme Networks and Foundry have had some bumpy financials related to enterprise spending.

Any negativity isn’t spilling into Interop however, as officials say attendance is up 25% from last year and scores of vendors will be making significant announcements.

Nortel and Foundry are two of them. Both plan to push hard on data centers and virtualization, which will be among the key themes at the conference.

Nortel is rolling out a new switch to virtualize services provided by several devices, including firewalls, application switches and SSL-acceleration appliances. The VSS 5000 switch consolidates and virtualizes these functions onto a single device, then orchestrates and provisions services to different enterprise departments or workgroups.

Nortel also is adding a new release of software to its Enterprise Routing System 8600 core switch. The software, Release 5.0, extends virtual services for LAN and data centers across the enterprise campus or metro network. It provisions services to all environments as a Layer 3 VPN, using existing MPLS control-plane RFCs, Nortel says. A version supporting campus/metro Layer 2 VPNs, based on Provider Link State Bridging, is slated for next year, the company says.

VSS 5000 will be available in the fourth quarter, and Release 5.0 of the ERS 8600 will be available later this quarter.

Foundry is unveiling a 16-port 10 Gigabit Ethernet module for its BigIron RX data center switch for high-density connectivity of servers and storage devices. The module brings the BigIron RX switch’s 10G density to 512 ports, which Foundry claims is double the 10G density of competitive data-center switches from Cisco and Force10 Networks, and quadruples the packet-per-second performance.