The Crimean War, why do some historians refer to it as " the first modern war"

The Crimean War of 1853-56 was one of the long series of Russo-Turkish wars, but it differed from the others in that Britain and France were involved. In fact, the military conflict was between Russia and a coalition of Great Britain, France, the Kingdom of Sardinia, and the Ottoman Empire (now Turkey). Some historians consider the Crimean War as "the first modern war", in that it utilised many new factors that weren¹t used in previous wars.
The Congress of Vienna introduced new rules into the balance-of-power game. Great Britain, France, Russia, Prussia, and Austria were now ded…