The Global Reported Arms Trade: The UN Register of Conventional Arms
https://www.un.org/disarmament/convarms/register/
Transparency in armaments is a key confidence-building measure. It may encourage restraint in the transfer or production of arms, and can contribute to preventive diplomacy.The UN Register of Conventional Arms (UNROCA) has received reports from more than 170 States. The vast majority of official arms transfers are captured by it.

Peacekeeping Research Hub
https://peacekeepingresourcehub.un.org/en/
United Nations Departments of Peace Operations (DPO) is pleased to introduce the newly re-designed Peacekeeping Resource Hub. The website is designed to serve as the primary resource for Member States, Peacekeeping Training Institutes, Peacekeeping Operations and the UN’s partners on peacekeeping-related issues in all six official languages. It serves as a repository for all official DPO and DPPA training and guidance materials, and provides links to other related UN documents and resources. It also offers links to real-time news and updates in the United Nations peacekeeping world.

UN Peacemaker
http://peacemaker.un.org/
United Nations (UN) Peacemaker is an online mediation support tool developed by the Mediation Support Unit (MSU) in the Policy and Mediation Division of the UN Department of Political and Peacebuilding Affairs (DPPA).
Intended for peacemaking professionals, it includes an extensive database of peace agreements, guidance material and information on the UN’s mediation support services.
UN Peacemaker is part of the UN’s overall effort to provide advice and support to the Secretary-General and his Representatives in their efforts to prevent, manage and resolve international disputes and internal conflicts. It is also intended to be useful to UN partners actively engaged in peacemaking efforts, including Member States, regional organisations, civil society, non-governmental organisations and national mediators.