彩信的接收，总是先收到一个以短信形式下发的push消息，然后去下载的。下面来看看push消息里面都含有哪些内容。相关协议OMA-MMS-ENC-V1_2-20050301-A.pdf
本文主要介绍notification部分。
首先通过modem上报的是一个二进制内容转换过来的字符串，比如本文接收的push消息是8c829861714e344930347047394130008d9089178031383235343230353737362f545950453d504c4d4e008a808e04000050008805810303f48083687474703a2f2f3132302e3139322e3133372e3133353a3138332f635a4e35483100
下面打开协议Multimedia Message Notification，开表3
Field Name Field Value Description
X-Mms-Message-Type Message-type-value = m-notification-ind Mandatory. Specifies the PDU type. X-Mms-Transaction-ID Transaction-id-value Mandatory. This transaction ID identifies the M-Notification.ind and the corresponding M-NotifyResp.ind X-Mms-MMS-Version MMS-version-value Mandatory. The MMS version number. According to this specification, the version is 1.2 From From-value Optional. Address of the last MMS Client that handled the MM, i.e. that sent or forwarded the MM. If hiding the address of the sender from the recipient is requested by the originating MMS Client and supported and accepted by the MMS Proxy-Relay, the MMS Proxy-Relay MUST NOT add this field to the M-Notification.ind PDU. The insert-address-token MUST NOT be used as the value of the field.第一个字段是8C，这个是字段标识，请参考Header Field Names and Assigned Numbers中的定义。
| Name | Assigned Number |
| Bcc | 0x01 |
| Cc | 0x02 |
| X-Mms-Content-Location | 0x03 |
| Content-Type | 0x04 |
| Date | 0x05 |
| X-Mms-Delivery-Report | 0x06 |
| X-Mms-Delivery-Time | 0x07 |
| X-Mms-Expiry | 0x08 |
| From | 0x09 |
| X-Mms-Message-Class | 0x0A |
| Message-ID | 0x0B |
| X-Mms-Message-Type | 0x0C |
| X-Mms-MMS-Version | 0x0D |
| X-Mms-Message-Size | 0x0E |
| X-Mms-Priority | 0x0F |
| X-Mms-Read-Report | 0x10 |
| X-Mms-Report-Allowed | 0x11 |
| X-Mms-Response-Status | 0x12 |
| X-Mms-Response-Text | 0x13 |
| X-Mms-Sender-Visibility | 0x14 |
| X-Mms-Status | 0x15 |
| Subject | 0x16 |
| To | 0x17 |
| X-Mms-Transaction-Id | 0x18 |
| X-Mms-Retrieve-Status | 0x19 |
| X-Mms-Retrieve-Text | 0x1A |
| X-Mms-Read-Status | 0x1B |
| X-Mms-Reply-Charging | 0x1C |
| X-Mms-Reply-Charging-Deadline | 0x1D |
| X-Mms-Reply-Charging-ID | 0x1E |
| X-Mms-Reply-Charging-Size | 0x1F |
| X-Mms-Previously-Sent-By | 0x20 |
| X-Mms-Previously-Sent-Date | 0x21 |
| X-Mms-Store | 0x22 |
| X-Mms-MM-State | 0x23 |
| X-Mms-MM-Flags | 0x24 |
| X-Mms-Store-Status | 0x25 |
| X-Mms-Store-Status-Text | 0x26 |
| X-Mms-Stored | 0x27 |
| X-Mms-Attributes | 0x28 |
| X-Mms-Totals | 0x29 |
| X-Mms-Mbox-Totals | 0x2A |
| X-Mms-Quotas | 0x2B |
| X-Mms-Mbox-Quotas | 0x2C |
| X-Mms-Message-Count | 0x2D |
| Content | 0x2E |
| X-Mms-Start | 0x2F |
| Additional-headers | 0x30 |
| X-Mms-Distribution-Indicator | 0x31 |
| X-Mms-Element-Descriptor | 0x32 |
| X-Mms-Limit | 0x33 |
从上可以看出这个字段是X-Mms-Message-Type ，然后我们在看看value表示什么含义，请看7.2.23. X-Mms-Message-Type field。
m-send-req = <Octet 128>
m-send-conf = <Octet 129>m-notification-ind = <Octet 130>从上可以看出是个notification。
继续往下分析
9861714e34493034704739413000 // 98表示X-Mms-Transaction-ID ，这是个Text-string。值是aqN4I04pG9A0
8d90 //X-Mms-MMS-Version 类型Short-integer value是90，解析方法是高四位中的最后三位表示主版本号，第四位为次版本号，所以版本号为1.0
89 17 80 3138323534323035373736 //89表示From， value是18254205776
2f545950453d504c4d4e00 // /TYPE=PLMN 表示收件人类型是device-address
8a80 //class
8e 04 00005000 //信息大小：size 20k，有时候下载前和下载后大小不一样，就是这个值不对。88 05 81 03 03f480 //有效期：25920083 687474703a2f2f3132302e3139322e3133372e3133353a3138332f635a4e35483100 //X-Mms-Content-Location