System.Security.Policy (mscorlib.dll)sealed class
public sealed class Zone : IIdentityPermissionFactory, IBuiltInEvidence {
// Public Constructors
   public Zone(System.Security.SecurityZone zone);
// Public Instance Properties
   public SecurityZone SecurityZone{get; }
// Public Static Methods
   public static Zone CreateFromUrl(string url);
// Public Instance Methods
   public object Copy(  );
   public IPermission CreateIdentityPermission(Evidence evidence);
 // implements IIdentityPermissionFactory
   public override bool Equals(object o);        
// overrides object
   public override int GetHashCode(  );    
// overrides object
   public override string ToString(  );    
// overrides object

This evidence class identifies the Internet Explorer security zone from where an assembly was loaded. The runtime assigns Zone evidence to an assembly by comparing the URL from where the assembly was loaded, with the security zone configuration in Internet Explorer. The type of Zone evidence is specified by passing a value of the System.Security.SecurityZone enumeration to the Zone constructor and can be accessed after construction through the SecurityZone property.

During policy resolution, the ZoneMembershipCondition class uses Zone evidence to evaluate whether code qualifies for membership of a CodeGroup.

Because the Zone class implements the IIdentityPermissionFactory interface, an assembly or application domain with Zone evidence will contain an appropriately configured System.Security.Permissions.ZoneIdentityPermission object in its grant set.

    Part V: API Quick Reference