If it's about peacekeeping, then Russia should accede to the AIE's demands that Russian forces (which only enjoy the confidence of the Transnistrian side and are an interested party themselves) be replaced by impartial international peacekeepers with no direct interest in the conflict.
If it's about peacekeeping, Russia and Transnistria should allow international experts back in to Transnistria to resume the destruction of the arms stockpile at Colbasna, arms which are of deteriorating condition and have little defensive value.
If it's about peacekeeping, then Russia should ensure that mechanisms are in place to ensure that Moldova respects the legitimate rights of people in Transnistria, the best such mechanism being Moldova's entry into the EU.
If it's about peacekeeping, then Russia, recognising Moldova's territorial integrity, should place moral, financial and political pressure on the Transnistrians to reintegrate.
If it's about peacekeeping...