The following procedure will help you create User-defined Network Resource Pools:

1. Bring up the Networking inventory using the vSphere Web Client by using the key combination Ctrl + Alt + 5.
2. Select the desired dvSwitch and navigate to Configure | Network resource pools and click on Reserve Bandwidth for virtual machine system traffic...:

3. On the Edit Resource Settings for Virtual Machine Traffic window, leave the Shares value at High and set a Reservation. This reservation is a bandwidth reservation per physical NIC. In this case, it is being set to 500 Mbps:

4. The Configured reservation will now be equivalent to the total number of participating physical NICs multiplied by the bandwidth reservation per NIC. (In this case, 500 Mbps x 4 vmnics = 2 Gbps). It is from this unused reservation quota that you can further divide the reservation among the network resource pools. Click on the  icon to bring up the New Network Resource Pool window:

5. On the New Network Resource Pool window, supply a Name, an optional Description, and the Reservation quota in Mbps or Gbps. Here we have reserved 1 Gbps (1,000 Mbps):

6. Now you could assign the NRP to the desired dvPortGroup. Click Edit Settings of the desired dvPortGroup and choose the Network resource pool to be used:

With this configuration, the dvPortGroup is guaranteed to receive the reserved bandwidth regardless of the bandwidth needs of other virtual machine traffic.