The U.S. Pacific Northwest (PNW) is one of the largest Internet infrastructure hubs for several cloud and content providers, research networks, colocation facilities, and submarine cable deployments. Yet, this region is within the Cascadia Subduction Zone and currently lacks a quantitative understanding of the resilience of the Internet infrastructure due to seismic forces. The main goal of this work is to assess the resilience of critical Internet infrastructure in the PNW to shaking from earthquakes. To this end, we have developed a framework called ShakeNet to understand the levels of risk that earthquake induced shaking poses to wired and wireless infrastructures in the PNW. We take a probabilistic approach to categorize the infrastructures into risk groups based on historical and predictive peak ground acceleration (PGA) data and estimate the extent of shaking-induced damages to Internet infrastructures. Our assessments show the following in the next 50 years: ~65% of the fiber links and cell towers are susceptible to a very strong to a violent earthquake; the infrastructures in Seattle-Tacoma-Bellevue and Portland-Vancouver-Hillsboro metropolitan areas have a 10% chance to incur a very strong to a severe earthquake. We also perform a case study of Integra’s long haul links in the PNW and show that links between Portland and Seattle are at greatest risk of damage. To mitigate the damages, we have designed a route planner capability in ShakeNet. Using this capability, we show that a dramatic reduction of PGA is possible with a moderate increase in latencies via backup routes and new deployments that minimize cost and PGA. We also show that cell tower corridors can be reinforced to maintain wireless connectivity between metro areas in a disaster scenario.