Windows XP standard firewall bypass
The challenge of "invisible" agents' creation is the key information security problem. Covert data transfer is the one of its subtasks. Thus under covert data transfer the creation of steganografic schemes in network protocols (covert channels) is understood. This paper purpose is to review the possibility of legal communication channel establishment in Windows system that will let to interact in the network "invisibly" for standard packet filters. The possibility of this channel creation is settled down.