Đang chuẩn bị nút TẢI XUỐNG, xin hãy chờ
Tải xuống
Các khách hàng SSH bên trái cung cấp xác thực đến máy chủ SSH trên bên phải. Kết nối ban đầu, khách hàng sẽ nhận được một phím máy chủ của máy chủ, do đó, trong tất cả các kết nối tiếp theo, khách hàng sẽ biết nó đang kết nối với cùng một máy chủ SSH. | Overview of SSH 13 As shown in Figure 1.6 the SSH process is as follows The SSH client on the left provides authentication to the SSH server on the right. In the initial connection the client receives a host key of the server therefore in all subsequent connections the client will know it is connecting to the same SSH server. This places less emphasis on the IP address of the SSH server which can be easily spoofed and more emphasis on the host key of the server which cannot be spoofed very easily. The SSH server determines if the client is authorized to connect to the SSH service by verifying the username password or public key that the client has presented for authentication. This process is completely encrypted. If the SSH server authenticates the client and the client is authorized the SSH session begins between the two entities. All communication is completely encrypted. The client server architecture for SSH provides the ability for clients to have a single source for authentication and or authorization. The single source for authentication authorization allows access only to the SSH service while access to various other services such as e-mail intranets extranets and IRC requires further authentication. Also with the use of SSH proxies described previously a single source of authentication can provide access to applications without the need for more usernames and passwords. SSH s Encryption Architecture One of the many benefits of SSH is that it provides a fully encrypted protocol for transferring information but what is the encryption architecture that SSH uses and how is it deployed This book does not explore in detail the encryption algorithms used or how they are implemented in SSH since optimization and implementation are the focuses of this book but I do briefly examine the architecture in order to provide some background knowledge of its deployment. SSH s implementation architecture is just as flexible as the protocol itself. SSH is compatible with the
