This article provides a description of the Efficient Mail Submission & Delivery protocol, or EMSD. EMSD is the e-mail component of the LEAP family of protocols.
The entire family of LEAP protocols has been designed with efficiency as a primary requirement, and each component protocol brings efficiency and functionality benefits to the users of miniaturized mobile devices. In particular, EMSD brings these efficiency benefits to the e-mail, or Mobile Messaging, application.
Mobile Messaging is just one of several applications for which there is a high efficiency premium in the mobile and wireless arena. Other applications which demand efficiency in the mobile environment are such things as web browsing, dictionary look-up, etc. From an industry-building perspective, however, e-mail is the most critically important of all wireless and mobile data communications applications. Mobile Messaging provides the user with a unique communications facility: the immediate delivery of important and time-critical information to the mobile recipient, wherever and whenever he/she happens to be. This is a capability which is not provided by phone, Fax, or any other tool in the modern user's array of communications options.
In fact, this capability represents the principal value of wide-area wireless networks to the end user, and this is why e-mail remains the dominant application for wide-area wireless networks. Furthermore, miniature hand-held mobile devices are extremely well-suited to the e-mail application. The same is not true for other applications, such as web browsing.
For all these reasons, e-mail is the key industry-building application, and this is why EMSD represents the right starting point for the LEAP family of protocols.
Throughout this article, we will make use of the following terms and definitions: