Secure Multipurpose Internet Mail Extensions (S/MIME) allows digital signatures to be attached to e-mail messages, such that the recipient can verify the identity of the signer.

安全多用途 Internet 邮件扩展（Secure Multipurpose Internet Mail Extensions，S/MIME）允许将数字签名附加到电子邮件消息上，这样接收方就可以验证签名者的身份。

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Instead, FOAF tools use digital signatures to associate an E-mail address with a document.

与此相反，FOAF工具使用数字签名来使电子邮件地址与文档关联。

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Soon after, the image began popping up in home windows and under people's e-mail signatures.

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We then started to incorporate the online outreach and response experience in our day to day operations to offer more complete marketing solutions (from consumer responses to e-mail signatures).

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The second of those strategies may be enacted with a new system called DomainKeys Identified Mail, which would embed encrypted digital signatures in e-mail messages.

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