vb.net code 39 Security Policy in Visual Studio .NET

Print Code 128 Code Set C in Visual Studio .NET Security Policy

Figure 8-1

The event log engine in Windows was completely rewritten for the 6.0 release of Windows (Windows Vista and Windows Server 2008). The performance and scale issues that affected the old event log engine are no longer significant. Where the old event log service had a maximum effective log file size of 4 GB (significantly less on 32-bit computers), logs using the new service can be up to 2^53-1 bytes in size more than a petabyte. And where the old log had a maximum throughput of only a few thousand events per second when configured as circular, the new log has a throughput of tens of thousands of events per second. The new event log engine exposes events to applications in XML format. This not only permits events to be self-descriptive, but also allows the engine to pre-filter events based

Part I:

on XPATH expressions. This allows rich filtering in applications like Event Viewer, and also allows narrowly targeted subscriptions monitoring applications can specify very precisely which events are of interest to them. Eric Fitzgerald, Senior Program Manager Forefront Security As mentioned earlier, most security events, with the exception of events related to the health of the audit subsystem, originate in components outside the audit subsystem. Each event is raised under a specific set of conditions. For most events, the conditions are:

In one case there is actually a third prerequisite. Resource managers are a specific kind of security reference monitor that arbitrate the access to a set of objects. When resource managers receive a request to access an object, they not only check the audit policy but also compare the access request with the specific audit settings on the object in question. As discussed in 2, objects in Windows have a security descriptor that describes various aspects of object-specific security policy. Part of the security descriptor data structure is the discretionary access control list (DACL). This is the list of permissions for the object that is used in access checking, and that most people refer to as the object s ACL. However, a second ACL is associated with each object, used to describe the audit policy specific to that object and to contain the integrity label (covered in 2) for that object. This ACL is officially designated the system access control list (SACL). Its construction is identical to the construction of a DACL, except that specific access control entries (ACEs) in the SACL will not grant permissions to users and groups, but rather will indicate which accesses to audit for specific users and groups. When an access check is performed, the resource manager must decide whether to generate an audit for that particular request. First the access check routine determines whether object access audit policy is enabled for that resource manager. If so, the access check routine compares the object s SACL to the result of the access check after the DACL is evaluated. In general, SACL evaluation is very similar to DACL evaluation. If a SACL is on the object and one or more of the SIDs in the requestor s token match any of the SIDs in the ACEs in the SACL, and any of the associated accesses in the access masks of matching ACEs match the requested access mask, an event is generated. The event records the requested access mask and is logged as a handle open event. This process applies to both successful and failed access requests, with the resultant event recording the success or failure of the handle open operation. The access mask is retained by the Object Manager, and when subsequent operations are performed using that handle, the first instance of any audited access causes an event to be generated.