9 Telnet and SSH
Quidway NetEngine20/20E
Configuration Guide - Basic Configurations
9-4
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
Issue 05 (2010-01-30)
Figure 9-3
Establishing an SSH channel in a LAN
Router
PC
LapTop
Ethernet
100BASE-TX
WorkStation
Server
PC running SSH client
Figure 9-4
Establishing an SSH channel in a WAN
Local LAN
PC run SSH client
Router
SSH router
Remote LAN
PC
WAN
Advantages of SSH
The product provides the functions of SFTP and STelnet client.
z
STelnet client
The Telnet protocol does not provide secure authentication. The contents that are
transmitted through the TCP are in plain text. This leads to security problems. The
system also faces serious threats from DOS attacks, the host IP address spoofing and
routing spoofing. Telnet services are prone to network attacks.
SSH implements secure remote access on insecure networks and it has the following
advantages compared to Telnet:
−
SSH supports RSA authentication mode. In RSA authentication, SSH implements
secure key exchange by generating public and private keys. These keys are generated
according to the encryption principle of the asymmetric encryption system. This
implements the secure process of sessions.
−
SSH supports Data Encryption Standard (DES), 3DES and AES.
−
The username and the password are both encrypted in the communication between
the client and the server of SSH. This is to prevent the password from being
intercepted.
−
SSH provides encryption to the transmitted data to guarantee security and reliability.
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SFTP client