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11.1 SSL Overview
The Secure Sockets Layer (SSL) protocol uses data encryption, identity authentication, and
message integrity check to ensure security of TCP-based application layer protocols.
Introduction to SSL
SSL is a cryptographic protocol that provides communication security over the Internet. It allows
a client and a server to communicate in a way designed to prevent eavesdropping. The server
must be authenticated by the client before they start to communicate, and the client can also be
authenticated by the server. SSL is widely used in ecommerce and online banking. It has the
following advantages:
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High security: SSL ensures secure data transmission by using data encryption, identity
authentication, and message integrity check.
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Support for various application layer protocols: SSL was originally designed to secure
World Wide Web traffic. SSL functions between the application layer and the transport
layer, so it can provide security for any TCP-based application.
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Easy to deploy: SSL has become a world-wide communications standard used to
authenticate websites and web users, and to encrypt data transmitted between browser users
and web servers.
SSL improves device security using the following functions:
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Allows only authorized users to connect to servers.
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Encrypts data transmitted between a client and a server to secure data transmission and
computes a digest to ensure data integrity.
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Defines an access control policy on a device based on certificate attributes to control access
rights of clients. This access control policy prevents unauthorized users from attacking the
device.
Terms
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Certificate Authority (CA)
A CA is an entity that issues, manages, and abolishes digital certificates. A CA checks
validity of digital certificate owners, signs digital certificates to prevent eavesdropping and
tampering, and manages certificates and keys. A world-wide trusted CA is called a root
CA. The root CA can authorize other CAs as subordinate CAs. The CA identities are
described in a trusted-CA file.
In the certificate issuing process, CA1 functions as the root CA and issues a certificate for
CA2, and CA2 issues a certificate for CA3. The process repeats until CAn issues the final
server certificate.
In the certificate authentication process, the client first authenticates the server's certificate.
If CA3 issues the server certificate, the client uses CA3 certificate to authenticate the server
certificate. If the server certificate is authenticated, the client uses CA2 certificate to
authenticate the CA3 certificate. After CA2 certificate is authenticated, the client uses CA1
certificate to authenticate CA2 certificate. The client considers the server certificate valid
only when CA2 certificate has been authenticated.
shows the certificate issuing and authentication processes.
Huawei AR1200-S Series Enterprise Routers
Configuration Guide - Security
11 SSL Configuration
Issue 02 (2012-03-30)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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