If you want to use TTL flash with a Canon camera you need a flash that would be compatible with Canon's E-TTL system. If you want to use a Sigma EF-610 DG ST flash it needs to be the Canon version. The Sigma EF-610 DG ST flash is also offered in Nikon, Pentax, Sony/Minolta, and Sigma versions. The following assumes you have the Canon version of the Sigma EF-610 DG ST flash.
You also need a TTL compatible set of triggers. The Phottix Strato™ II Multi 5-in-1 Wireless Flash Trigger is a manual control only trigger set. They won't allow you to use E-TTL.
There are other cheap flash trigger sets that will allow you to use E-TTL with a Canon EOS DSLR and a Canon E-TTL compatible flash such as you Sigma EF-610 DG ST.
The Yongnuo 622C is one such system. Each unit costs about $40 in the U.S. You can either use two YN-622C transceivers with one transmitting from the camera's hot shoe and the other receiving attached to the flash or you can use a YN-622C-TX transmitter on the camera and a YN-622C with the flash.
The advantage of the transmit only YN-622C-TX is that it has a LCD display panel that makes it much easier to change settings compared to using the YN-622C which only has a few buttons and indicator lights and requires many of the settings to be made using the flash control section of the camera's menu. The LCD display on the YN-622C-TX is both more intuitive to use and faster to access than the camera's external flash control menu, especially if you are controlling multiple flashes in different groups and want to use some manually and others in E-TTL mode.
Note: Models such as the 1000D/Rebel XS that was introduced before the EOS 5D Mark II in late 2008 do not have the in camera menu to control external flashes. This would severely limit the usefulness of the YN-622 system without a YN-622C-TX transmitter.
I use the YN-622C system. I have a single YN-622C-TX that I use on the camera's hot shoe to control several YN-622C triggers attached to various flashes. They work with any flash that is Canon E-TTL compatible: My Canon 430EX II and 580EX II, as well as several Canon versions of Yongnuo flashes. The YN685 flash even has a 622C receiver built in, so there is no need to attach a trigger to it. I've been very happy with the capabilities and performance of the 622C system, especially for the affordable price at which they sell.
The Godox X1C (C=Canon) is another such system that is fairly affordable. The Godox X1T-C offers a user interface with more information than the base X1-C transmitter, similar to the YN-622C-TX in comparison to the YN-622C. Unfortunately, as of September 2016, the Godox system seems to still be in a "beta" stage of development. Every time they update the firmware to solve one bug it seems they create another bug in the process. If they can ever get all of the kinks worked out it appears to be a very promising system, but for now it seems to be not quite ready for prime time.