The use of surge protectors to protect sensitive equipment from lightning hits and surges on Ethernet data lines has become more important than ever with the advent of faster standards like 100 and 1000Base-T Ethernet. The faster data speeds have required equipment manufacturers to use fragile high speed components. The need to keep cost low has meant the Ethernet interface is now integrated onto the main PCB assembly, designs with minimal part count and the use of low cost (lower power) components. A surge that would have left an older “beefy” 10Base-T interface untouched could easily destroy a sensitive 100/1000Base-T interface. In the past if a 10BaseT interface was damaged, it was easily replaced at minimal cost. With modern equipment having integrated 100/1000Base-T interfaces, this is not the case anymore. The Motherboard or more likely the entire piece of equipment will need to be replaced. The risk of not using an external surge protector is higher than ever. The use of a surge protector on an Ethernet line is not without its consequences however. All Ethernet surge protectors will degrade the performance of the Ethernet line. The use of protective components that inherently have a capacitive component as well as the limitations of PCB layout techniques contribute to the degradation. The degradation is in the form of increases in line insertion loss, phase distortion, crosstalk, degraded common mode rejection, and possible ground loops. The use of two protectors on each end of the line will provide protection for each end against surges, at the cost of increased line loss and the possibility of introducing a ground loop into the line. HAKEL offers multistage surge protectors that offer much higher levels of surge protection compared to competitor’s products. These surge protectors will survive surges over 100 times higher than a standard design. The additional stages of protection do contribute higher losses however and will shorten the maximum line length over a single stage design.