1. CDR in securities

CDR is the abbreviation of China Depository Receipt in English. The Chinese meaning is: China Depositary Receipt, which is a specialized representation of depository receipts (DR) in the Chinese market. title. Also known as Chinese depositary receipts, they are depository receipts issued to Chinese investors and traded in the Chinese securities market.

Depository Receipts (DR), also known as deposit receipts or deposit certificates, refer to transferable certificates that represent the securities of foreign companies that are circulated in a country’s securities market. They belong to companies. Financial derivatives in the field of financing business.

Take stocks as an example. Depositary receipts are generated like this: in order to circulate their stocks abroad, a listed company in a certain country entrusts a certain amount of stocks to an intermediary institution (usually a bank, called The custodian bank will notify the foreign depositary bank to issue depositary receipts representing the shares locally, and then the depositary receipts will start trading on foreign stock exchanges or over-the-counter markets. The parties to depositary receipts include issuing companies and custodial institutions in China, and depository banks, securities underwriters and investors abroad. Depositary receipts generally represent company stock, but sometimes bonds.

2. CDR format file

CDR format is a special graphics file format of the famous drawing software CorelDRAW. Since CorelDRAW is a vector graphics drawing software, CDR can record the attributes, location, paging, etc. of the file. However, it has poor compatibility. It can be used in all CorelDraw applications, but other image editing software cannot open such files.

3. CDR in mobile communications

CDR (calling detail records) is a call detail record, which describes the entire process of call connection. The parameters recorded in the CDR come from the original signaling message data. Further analysis and processing of some important parameters in the record can provide an analysis basis for fixed telephone network or mobile telephone network services. To realize CDR statistics, you must first track various signaling messages of the same call process, and then obtain business information from these messages. For different application parts, the message processes have different associations. The CDR contains TUP partial records and ISUP partial records.

Taking ISUP as an example, its CDR record should include the following content:

CDR type: including response charging, response free, response, failure, timeout, incomplete, length is 1 byte;

Link number: length is 2 bytes;

Encoding type: indicates 14 or 24-bit encoding, length is 1 byte;

OPC: source signaling point encoding , 3 bytes in length;

DPC: destination signaling point code, 3 bytes in length;

CIC system number: circuit identification code, 2 bytes in length;

CIC time slot number: circuit identification code, length is 2 bytes;

Start time: indicates IAM or IAI time, length is 5 bytes;

ACM time: represents the difference between ACM and the start time, the length is 5 bytes;

Response time: represents the difference between ANC (or ANN or ANM) and the start time, the length is 5 bytes;

REL time: represents the difference between the REL message and the start time, the length is 5 bytes;

RLC time: represents the difference between the RLC message and the start time, the length is 5 bytes;

Talk time: represents the difference between CBK (or CLF) and ANC time, the length is 5 bytes;

Occupied time: the difference between RLG and start time, the length is 5 bytes;

Occupation time: the difference between RLG and start time, the length is 5 bytes;

Calling user number: length is 20 bytes;

Called user number: length is 20 bytes;

Redirect number: used for call transfer, The length is 20 bytes;

ISUP service category: the length is 1 byte;

Call release reason: the length is 1 byte.

4. CD-RCD-R is the abbreviation of CD Recordable. Optical disc recording is a write-once, read-multiple (Write Once, Read Multiple) medium. It can be used like a standard optical disc. Compared with other media, the advantage of CD-R is that it can be played and used by standard optical disc players. The disadvantage is that you can't rewrite it.