A good analysis of the violence in the Sinai:
“Between 2004 and 2015, the Sinai insurgency has grown from mainly an urban terrorism campaign of bombing soft targets (such as the Taba Hilton in 2004) to a structured, low-to-mid level insurgency, aiming primarily for “hard” targets (such as Battalion 101 Camp in el-Arish, the HQ of the military campaign, dubbed “Sinai’s Guantanamo” by locals).”
IR Theory & Practice 