KTUL received the following official statement from CTB/McGraw-Hill that addressed the testing interruptions that took place in public schools in Oklahoma today:
Earlier today, April 21, all of McGraw-Hill Education experienced a network service interruption that impacted all areas of the company as well as some of our customers, including certain schools that administered CTB statewide assessments. The interruptions started at approximately 9am ET and were resolved by approximately 12pm ET. While many students have been testing successfully throughout the morning, we understand that as a result of these issues, the Oklahoma State Department of Education suspended testing for the day for all affected school districts in Oklahoma.We have identified the root cause of today's event as an intermittent service interruption in our redundant network addressing service. After confirming that the interruption was not caused by a denial of service attack, we worked with our technology vendor to isolate and correct the troubled network electronics. Although all systems are running as anticipated, we continue to provide enhanced network monitoring and management to ensure the health and stability of the McGraw-Hill Education network. The system has been available and operational since 12pm ET.
We note that today's event is unrelated to the capacity of CTB's IT infrastructure, which has been greatly enhanced since 2013. Over the past year, CTB has increased the capacity of its infrastructure by adding more servers and memory. We also conducted thorough performance testing with both simulated load testing and live traffic to ensure there is enough capacity to handle much heavier testing volumes than are actually expected.
We sincerely regret the inconvenience and disruption that this interruption caused schools today. We will provide any further information as it becomes available.