MPLS, Multi Protocol Label Switching, is a suite of protocols that will give IP-based networks the same service guarantees as circuit switched networks (aka the traditional phone system). This is especially crucial in VPNs which require controllable efficient tunnels through which proprietary network traffic travels. Cisco is one of the biggest proponents of MPLS and this book is written by two Cisco engineers. The greatest value of this book will be in the detailed configuration examples provided by the authors.