It is impossible for the electronic signature technology to resolve the problems of the certainty of the public key and the possibility of the private key holders denying the signed document 但是如何解决公共密钥的确定性以及私人密钥持有者否认签发文件的可能性问题，则是电子签名技术本身无法解决的问题。
2.
Chinese relatives or friends may request issuance of certificates on behalf of someone now living abroad . relatives and friends should have specific written authorization from the interested party before they request civil documents 现居海外者，其在中国的亲友可代为要求签发文件，而在要求签发公民文件前，其亲友应有当事人的书面授权。
