<PackageReference Include="System.Security.Permissions" Version="10.0.2" />

System.Net.PeerToPeer.Collaboration.PeerCollaborationPermissionAttribute

Allows security actions for PeerCollaborationPermission to be applied to code using declarative security. This class cannot be inherited.
namespace System.Net.PeerToPeer.Collaboration { public sealed class PeerCollaborationPermissionAttribute : CodeAccessSecurityAttribute { public PeerCollaborationPermissionAttribute(SecurityAction action); } }