
200 Architectural Design of an Energy-Efficient Router
Mbps to 8 Gbps. Since not all components in NetFPGA support operating
at a frequency different to the default value, it is difficult to directly measure
the reduction in energy saving of components supporting frequency scaling.
Energy conservation could only be estimated using Equation 7.19 in Section
7.3. However, the rate reduction could be measured by exploiting the Reg-
ister System of NetFPGA. The register interfaces allow software running on
host system to send data to and receive data from the hardware modules. A
few registers are used for recording operating time of each frequency in the
protot ...