Refurbed The Cisco 2503 series routers provide a variety of models designed for branch office and remote site environments. Cisco 2503 routers come with Flash EPROM technology for simplified software maintenance. These systems support a variety of Cisco IOS software feature sets, so you can choose a feature set that supports your specific protocol environment. The Cisco 2503 software feature sets range from an IP and bridging-only to the full array of Cisco's software functionality, including APPN and RMON.Mission-specific models contain less memory and less hardware functionality to support a subset of protocols. Each mission-specific model can be upgraded to full router capability by downloading a new Cisco IOS software feature set and, if necessary, adding memory.