The range of Cisco® 10GBASE XENPAK modules offers a wide variety of 10 Gigabit Ethernet connectivity options for data center, enterprise wiring closet, and service provider transport applications. Main features of Cisco 10GBASE XENPAK modules include: -Supports 10GBASE Ethernet. -Hot-swappable input/output device plugs into an Ethernet XENPAK port of a Cisco switch or router to link the port with the network. -Provides flexibility of interface choice. -Supports "pay-as-you-populate" model. -Supports the Cisco quality identification feature that enables a Cisco switch or router to identify whether the module is a Cisco certified and tested XENPAK module. Cisco XENPAK-10GB-ER / -ER+: Supports a link length of up to 40 km on SMF (G.652).