The Treaty of Vienna was the treaty that ended the Napoleonic Wars and punished France. The French army had been dispersed and Napoleon exiled on an island. Diplomats from most European nations met at Vienna in 1815, including France, the defeated power. Although there were so many ambassadors, it was only the four major European powers - England, Russia, Austria, and Prussia - that decided on the terms of the treaty. By the time the treaty was given to and imposed on France, a barrier of strong states had been either pointed out or created outright (as in the case of the Netherlands) along France's borders. Other than that, the Treaty of Vienna was not truly excessive or even haughty in it's aims, and France redily accepted it's terms - which included a debt to be paid to the victors and minor military controls. Due to the successfulness of this treaty, peace reigned in Europe for several decades.
On the other side of the coin is the Treaty of Versailles. The new state of Europe seemed deathly afraid that something like the Great War could happen again, and were determined to stop Germany's ability to make war forever. France practically wanted Germany burned at the stake. The Allies met in Paris to come up with a treaty for Germany - the Treaty of Versailles - Germany was not invited, nor even given a hearing on the document until it was handed to them to sign. By the treaty, Germany lost all of it's overseas colonies and private property held by German citizens; its army was reduced to almost nothing; its navy, air force, and merchant marine were eliminated (and forbidden to ever be rebuilt); and finally, Germany was to pay for all damages and debts incurred by all Allied nations during the war (an unspecified amount, which left it open to be increased at any time). Germany refused the treaty when it was presented to them, but were forced to sign when the Allies threatened further hostilities unless they signed. The treaty caused huge unrest in Germany and resentment towards the Allied countries that had imposed such ridiculous concessions upon them. It would have been hard to make a more unbalanced, unforgiving, harsh, and politically amateurish document to attempt to end a war and create peace.
To say that the Treaty of Versailles was more modern or up-to-date is a bit like calling nuclear war a civilized kind of war. The Treaty of Versailles attempted to destroy the defeated nation of Germany, while the makers of the Treaty of Vienna merely wanted to tell France not to try to take over the world again. The Treaty of Vienna treated its victim like human beings - Versailles treated Germany like a rabid dog. Far from "realistic", Versailles was a greedy and vengeful treaty that had no place being in the (then) modern world, and a treaty similar to that at Vienna imposed on Germany at the end of World War I would have done much more good for Europe than Versailles did.