In a small saucepan dilute the broth with 2 cups water, bring it to a boil, and keep the broth at a bare simmer.
In a heavy saucepan cook the bell pepper and the artichoke hearts in 1 tablespoon of the oil over moderate heat, stirring, for 2 minutes and transfer them with a slotted spoon to a bowl.
In the heavy pan cook the onion in the remaining 2 tablespoons oil over moderately low heat, stirring, until it is softened, stir in the prosciutto and the rice with a wooden spatula, and cook the mixture over moderate heat, stirring, for 1 minute, or until the rice is coated well with the oil.
Add the wine and cook the mixture over moderately high heat, stirring, for 1 to 3 minutes, or until the wine is absorbed, add 1/2 cup of the simmering broth, and cook the mixture at a vigorous simmer, stirring, for 3 to 5 minutes, or until the liquid is absorbed.
Continue adding the broth, about 1/2 cup at a time, stirring constantly and letting each portion be absorbed before adding the next, until only 1/2 cup of the broth remains.
Stir in the vegetables and 1/3 cup of the remaining broth and simmer the mixture, stirring, for 1 minute, or until the liquid is absorbed. (The risotto should be creamy, but the rice grains should be al dente.)
If necessary add the remaining broth and cook the risotto in the same manner until the rice is al dente.
Remove the pan from the heat and stir in the Parmesan, the parsley, and the white pepper.