Investment protection and field upgradable capability the pvdm3 module has the same form factor and is used across cisco 2900 and 3900 series integrated services routers the field upgradable capability can help you easily scale your voice deployments wide range of codec support the pvdm3 module supports a wide range of codecs of different complexities it supports all codecs that are supported by the pvdm2 modules high density and flexibility the pvdm3 module portfolio has up to 4 times hig