There were no quotas or limits on the size of user mailboxes, no limits on personal agents, or limits on full-text indexing or searching.

用户邮件大小没有配额或限制，个人代理没有限制，或全文索引或搜索没有限制。

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The structure of the system, mail service protocols, mode of messaging, allocation of mailboxes as well as personal security for authentication and access control measures are discussed in this paper.

文中论述了该系统的结构、邮递服务协议、邮递方式、信箱的管理及信件的保密和存取控制手段等问题。

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