然而，这个策略使用对称加密。
使用预先交换的密钥(对称加密)。
Using keys that were previously exchanged (symmetric encryption).
对称和非对称加密间的差异
说明如何进行对称和非对称加密。
因为涉及到一对密钥，所以它也称为非对称加密。
Since a pair of keys is involved, it is also called an asymmetric cryptography.
不对称加密：公钥加密(这两个术语是同义词)。
Asymmetric cryptography: Public-key cryptography (these two terms are synonyms).
对于对称加密算法，您可以使用AES128或AES256。
For symmetric encryption algorithms, you can use either AES128 or AES256.
当使用非对称加密对很多消息签名时，大多数处理时间花在签名上。
When you're signing a large number of small messages with asymmetric encryption, most of your processing time is spent on the signature step.
SymmEncr：需要使用一个客户端生成您的密钥进行对称加密。
SymmEncr: Require symmetric encryption using a client-generated secret key.
通过这两种安全性配置，客户端和服务之间的消息交换使用了对称加密。
With both security configurations, symmetric encryption is used for the messages exchanged between the client and the service.
使用以前生成的密钥加密SOAP消息中的敏感数据（对称加密）。
Use the key that was previously generated to encrypt the sensitive data within the SOAP message (symmetric encryption).
此安全策略使用非对称加密执行数字签名与验证、加密和解密。
This security policy performs digital signing and verification, encryption and decryption using asymmetric cryptography.
AsymmBinding：需要非对称加密，使用双重证书。
AsymmBinding: Require asymmetric encryption using dual certificates.
清单6中的示例使用非对称加密技术签署所有消息，提供图书信息。
The Listing 6 example USES asymmetric encryption to sign all the messages providing book information.
非对称加密技术是一种新的加密技术，数字签名是其最重要的应用。
A symmetric cryptography is a new cryptography. Digital signature is the most important application of asymmetric cryptography.
克服，你需要使用对称加密方案和需要的关键每一次你读/写文件。
To overcome that, you'd need to use a symmetric encryption scheme and require the key each times you read/write the file.
但对称加密的密钥管理较困难，这会成为影响安全和效率的一个因素。
But the key is relatively difficult to manage, which will influence the security and efficiency.
密钥的RC4加密后生成的初始密钥交换中的RSA非对称加密使用。
The RC4 encryption keys are generated after an initial key exchange in which RSA asymmetric encryption is used.
但在下个月的专栏中，我们将首先讨论使用对称加密及常规WS - Security。
But first, in next month's installment, I'll discuss using symmetric encryption with regular WS-Security.
WS - Security之所以常常伴随性能损失主要是因为大量使用了非对称加密。
A major part of the WS-Security performance cost comes from the wide use of asymmetric encryption.
由于使用了不同的密匙进行加密和解密消息，因此这种形式的加密被称为不对称加密。
Because separate keys are used for encrypting and decrypting messages, this form of cryptography is called asymmetric encryption.
但是它也有缺点，包括不对称加密的性能开销和每个客户端获取和维护证书的繁琐管理。
But it also has drawbacks, including the performance overhead of asymmetric encryption and the management headaches of obtaining and maintaining certificates for each client.
对于非对称加密算法，您可以使用RSA1024、RSA2048或RSA4096。
For asymmetric encryption algorithms, you can use RSA1024, RSA2048, or RSA4096.
另外一种方法是对称加密，但是使用对称加密时，您必须拥有只有参与消息交换各方才知道的密钥。
The alternative is symmetric encryption, but with symmetric encryption you must have a secret key known only to the parties involved in a message exchange.
您还应该检查他们是否期望对称加密的认证(MAC,HMAC，认证密码或签名)。
You should also check if they would expect authentication (MAC, HMAC, authenticated cipher or a signature) for the symmetric encryption.
Metro甚至比直接使用对称加密实现WS - Security还要快一些，大约快30%。
Metro does even better with direct use of symmetric encryption with WS-Security, running about 30 percent faster.
若要与远端的一方沟通对称金钥和IV，通常会使用非对称加密来加密对称金钥和IV。
To communicate a symmetric key and IV to a remote party, you would usually encrypt the symmetric key and IV using asymmetric encryption.
本文提出了一类新的认证加密方案，这类方案首次将消息可恢复签名和对称加密有机结合。
A new type of authenticated encryption schemes is proposed. It first combines signature with message recovery schemes and symmetric encryption schemes together.
SSL协议采用了对称加密、非对称加密、信息摘要、数字签名、数字证书等密码学技术。
SSL protocol USES symmetric encryption, asymmetric encryption, message digest, digital signature, digital certificate and other cryptographic techniques.
SSL协议采用了对称加密、非对称加密、信息摘要、数字签名、数字证书等密码学技术。
SSL protocol USES symmetric encryption, asymmetric encryption, message digest, digital signature, digital certificate and other cryptographic techniques.
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