Designed for both service providers and enterprises, Nortel Networks Multiservice Switch (MSS) 7400 can be used for access adaptation and backbone switching supporting Layer 2 VPNs, Layer 3 VPNs, circuit emulation, voice services and wireless applications. The MSS 7400 portfolio consists of the MSS 7420, MSS 7440, MSS 7460 and MSS 7480.
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http://products.nortel.com/go/product_content.jsp?parId=0&segId=0&catId=-9785&prod_id=26541&locale=en-US