But commercial traffic must be different. That goes to the Port of Eilat to and from the East, and to Jaffe, Acco, Ashdod, etc., to and from the West. The Six Day War was fought over, inter alia, Egyptian attempts to block Eilat shipping.
That goes for military traffic too. The US sends its warships through on a regular bases. the Iranians has sent their ships through since 1979.
There are rules of navigation set up by the Suez Canal Authority(all 213 pages worth)
http://www.luckydolphin.com/pdf/suez_canal_rules_of_navigation.pdf