Before it restarts, warning messages state the switch is running the feature set without a valid license. After the usage period expires, the switch continues to use the temporary software license until it is restarted. A temporary software license is limited to a usage period (around 60 days). So when you request for a license on the switch, the first thing that you need to have is this ' UDI' of the device This information can be found using the 'show license udi' command on the switch CLI. The product ID identifies the type of device. Serial number is an 11-digit number that uniquely identifies a device. A unique device identifier is made up of two components: the product ID (PID) and serial number (SN). In other words, licenses are locked to the switch's unique device identifier(UDI). This Software Activation License is unique to a specific device. Software Activation is a feature that is preinstalled on the switch, which allows you to install the software license for a feature set. A switch can have more than one software license, but you can enable only one license at a time. A software license applies only to a specific feature set. The software licenses are not affected by Cisco IOS software upgrades. 3560-X and 3750-X Series support the LAN Base, IP Base, and IP Services feature sets. 3560-E and 3750-E Series support the IP Base and IP Services feature sets (IP Services has all the feature sets that Advipservices had advipservices is End Of Sale : ) IP Services: Advanced Layer 3 switching (IPv4 and IPv6) features.IP Base: Enterprise access Layer 3 switching features.LAN Base: Enterprise access Layer 2 switching features.T hese are the 3 feature sets available on 3K platform of switches

Cisco 3750 ipservices license