{"id":12510,"date":"2026-09-22T10:46:14","date_gmt":"2026-09-22T02:46:14","guid":{"rendered":"https:\/\/www.dccochina.com\/?p=12510"},"modified":"2026-09-22T10:46:20","modified_gmt":"2026-09-22T02:46:20","slug":"how-can-a-125khz-proximity-card-be-numbered-and-encoded-without-duplicate-credential-ids","status":"publish","type":"post","link":"https:\/\/www.dccochina.com\/es\/how-can-a-125khz-proximity-card-be-numbered-and-encoded-without-duplicate-credential-ids\/","title":{"rendered":"How Can a 125kHz Proximity Card Be Numbered and Encoded Without Duplicate Credential IDs?"},"content":{"rendered":"

To avoid duplicate credential IDs on a 125kHz proximity card, simply printing different numbers on the card surface is not enough. First, define the credential format used by the access control system and assign non-overlapping ID ranges. Then encode each card using a controlled production database. Before writing data, we must verify the uniqueness of each credential to be encoded; after encoding, we perform readback verification to ensure the facility code, card number, bit structure, and printed number match the production records.<\/p>\n\n\n\n

For high-volume orders, we treat the numbering process as a controlled credential management procedure:<\/p>\n\n\n\n

Credential Format \u2192 Facility\/Site Code \u2192 Reserved ID Range \u2192 Duplicate Check \u2192 Card Encoding \u2192 Readback Verification \u2192 Production Records<\/p>\n\n\n\n

This process prevents the reuse of previously issued numbers and ensures that every 125 kHz RFID card delivered to the customer contains the intended credential values.<\/p>\n\n\n\n

The Uniqueness of 125kHz Proximity Card Credentials Begins with the Numbering Architecture<\/h2>\n\n\n\n

The primary question is not merely \u201cWhat number should be printed on the card?\u201d but rather: What complete credential value will the access control system recognize as unique?<\/p>\n\n\n\n

A single 125kHz Proximity Card may contain multiple numbers serving different purposes. These include the transponder identifier assigned by the manufacturer, the encoded access control credential data, and the decimal number printed or laser-engraved on the Card\u2019s surface. Do not treat these values as interchangeable. For access control projects, the relevant credential ID typically depends on the format required by the card reader and access control system.<\/p>\n\n\n

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\"The<\/figure>\n<\/div>\n\n\n

Determine the Credential Format Before Assigning Numbers<\/h3>\n\n\n\n

A common example is the Wiegand protocol-based credential format, in which the transmitted credential data includes a facility code (or site code), an individual card number, and parity information. HID\u2019s documentation also clearly distinguishes between the programming format, facility code, and starting credential number when customers order credentials.<\/p>\n\n\n\n

If two cards have different facility codes, they are not considered identical credentials, even if the card numbers printed on their surfaces are the same. Conversely, if two cards that look different transmit the same credential data to the access control system, this may result in duplication.<\/p>\n\n\n\n

Therefore, we define uniqueness based on the complete credential structure, such as:<\/p>\n\n\n\n

Format + Facility Code + Credential Number<\/strong><\/p>\n\n\n\n

rather than simply verifying the numbers printed on the Card\u2019s surface. Before beginning production, we require the customer to provide or confirm the following information:<\/p>\n\n\n\n