Electromagnetic cards, also known as magnetic stripe cards or magstripe cards, are a type of payment and identification card that use magnetic technology to store and retrieve data. These cards have been widely used for various purposes, including credit/debit cards, access control cards, loyalty cards, and more. Here’s a detailed explanation of electromagnetic cards:
- Magnetic Stripe Technology: The magnetic stripe on the back of the card is a narrow band of magnetic material that can store digital information. It is typically made of magnetic particles suspended in a plastic-like film. The stripe is generally black or brown and is located on the back of the card.
- Data Encoding: The data on the magnetic stripe is encoded using a series of magnetic fields that represent binary data. These magnetic fields can be polarized in two directions, typically referred to as “north” and “south” poles, representing 0s and 1s, respectively.
- Magnetic Stripe Structure: The magnetic stripe is divided into three tracks, each capable of storing different types of data. The tracks are typically distinguished by their locations and data storage capacities:
- Track 1: This is the topmost track on the magnetic stripe and is the most widely used. It stores alphanumeric data and has a capacity of 79 characters. Track 1 usually contains the cardholder’s name, account number, and expiration date.
- Track 2: Located below Track 1, it is the second most common track used. It has a capacity of 40 characters and typically stores the cardholder’s account number, encrypted PIN, and other data.
- Track 3: Positioned below Track 2, this track has the largest capacity, approximately 107 characters, and is less common than the first two tracks. It is used less frequently and can hold additional information if required.
- Data Read and Write Process: Electromagnetic cards are read and written using card readers equipped with magnetic heads. When the card is swiped through the reader, the magnetic head detects the changes in magnetic polarity on the stripe and converts them into electrical signals. These signals are then decoded by the card reader, enabling access to the stored data.
- Advantages:
- Cost-effective: Magnetic stripe cards are relatively inexpensive to produce compared to other card technologies.
- Widely Accepted: Magstripe technology has been in use for decades, making it widely accepted and compatible with numerous card readers.
- Simplicity: The technology is straightforward, making it easy to implement and use.
- Disadvantages:
- Limited Security: Magnetic stripes offer limited security as the data is not encrypted, making them susceptible to skimming and cloning.
- Prone to Wear: Magnetic stripes can wear out over time with frequent use, leading to data loss or reading errors.
- Data Capacity: The amount of data that can be stored on a magnetic stripe is relatively small compared to other modern card technologies.
- Transition to Chip Technology: Due to increasing security concerns, many countries have transitioned from magnetic stripe cards to chip-based cards (EMV technology), which offer improved security features, including data encryption and dynamic authentication. Chip cards are commonly referred to as “smart cards.”
In summary, electromagnetic cards, or magnetic stripe cards, use magnetic technology to store and retrieve data. While they have been widely used for many years, their use has diminished in favor of more secure chip-based cards in recent times.