HUNTSVILLE, Ala. -- ADTRAN(TM), Inc. (NASDAQ: ADTN) today announces a new version of the ADTRAN Operating System (OS), version 4.1, that adds Virtual Private Networking (VPN) to the low-cost, access router alternative, the NetVanta(TM) 3000 Series. This new ADTRAN OS upgrade expands market opportunities by allowing businesses of all sizes to secure corporate connectivity using the public Internet with standard-based IPSec protocols and various encryption algorithms like DES, 3DES, and AES. When equipped with the ADTRAN OS upgrade, the NetVanta 3000 Series of access routers interoperates with other IPSec based products including ADTRAN's NetVanta 2000 Series of dedicated VPN/Firewall appliances and the NetVanta VPN software client. "There are two schools of thought when it comes to implementing Virtual Private Networks," said Tim Saunders, vice president product management, ADTRAN Enterprise Networks Division. "Some users want a dedicated appliance to perform VPN and firewall functions, separate from the access router. Others prefer a single box solution that performs all the functions. Either way, ADTRAN can now satisfy both requirements. The NetVanta 2000 Series is a dedicated VPN/Firewall platform, while the NetVanta 3000 Series is an access device that can terminate the wide area circuit, and perform all routing, firewall, and VPN functions." Adtran Inc.