You can monitor network devices (such as routers) to determine if the device is responsive or slow.

• Go to Servers & Devices -> Network Devices 
• Click the New () button
• Enter the appropriate information into the corresponding text boxes
• Select the checkbox  () next to Display on Dashboard as 'Network Infrastructure' to have the device appear on the Dashboard (Note: the device will not appear on the dashboard if this option is not selected)
• Click OK to save the changes