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Mobile messaging technologies and services sms ems and mms phần 7

Ví dụ đầu tiên cho thấy rằng các ứng dụng không thực hiện bất kỳ thời gian tiết kiệm ánh sáng ban ngày (giá trị FALSE). Ví dụ thứ hai chỉ ra rằng ánh sáng ban ngày tiết kiệm thời gian là quan sát và thời gian mùa hè là 6 giờ sau UTC (mùa hè thời gian là từ 7 tháng Tư đến 27 Tháng 11 2002) Vị trí địa lý. | 216 Mobile Messaging Technologies and Services Figure 6.8 Base64 and quoted-printable encoding decoding methods 6.10.2.3 Content Transfer Encoding The transfer encoding field indicates which encoding mechanism has been used to encode the original message content for transport purposes. The encoding is usually necessary for allowing data to be transported over 7-bit transfer protocols such as SMTP. The indication of which encoding has been applied to the original message is necessary for the message recipient to be able to reconstruct the message in its original form after transfer. The example below indicates that the original 8-bit encoded message has been encoded in 7-bit data for transfer purpose according the base64 encoding method Content-Transfer-Encoding base64 8bit Three encoding decoding methods are commonly used in MIME for the following domains binary 8-bit data and 7-bit data. These methods are known as the identity quoted-printable and base64. The identity method means that no encoding has been applied to the original message. The encoding decoding processes for quoted-printable and base64 methods are depicted in Figure 6.8. The quoted-printable method encodes an original message in a form that is more or less readable by a subscriber. On the other hand the base64 method encodes the message in a form which is not user-readable but which presents the advantage of being a more compact data representation. Such encoding methods are particularly relevant for transfers over the MM3 and MM4 interfaces. Note that transfers over the MM1 interface are carried out in a binary domain. Consequently there is no need to use one of the three encoding methods as identified in this section for the MM1 interface. 6.10.2.4 Content identification and description The content-id field provides a unique identification for one given body part of a multipart message. This is to be compared with the Message-ID of the RFC 822 format which provides a unique identifier for the .