(Bloomberg) -- In a market that’s captured the attention of global finance for allegedly making $1 billion for Jane Street Group, many trading firms are employing a relatively simple strategy: short volatility.Most Read from BloombergThese Flight Routes Suffer the World’s Worst TurbulenceNvidia Delivers on AI Hype, Igniting $140 Billion Stock RallyCiti Trader Got 711 Warning Messages Before Sparking Flash CrashOne Dead After Singapore Air Flight Hit By Severe TurbulenceThe trade, or variations o