**6. NFC tags**

In an NFC system, there is always an element which functions as the receptor in passive mode, such as NFC tag. NFC tag, also known as the smart tag or information tag, is a small, printed circuit which act as a bit of storage memory along with a radio chip attached to an antenna [18]. It works in a passive mode, during which it does not have its own power source but uses power from the NFC device that communicates with it via magnetic induction. NFC tags have a few inches of working distance, NFC device must be very close to read the tag. NFC tags are used for a variety of applications in our day-to-day life, such as payments, launching websites, virtual visiting cards, lock/unlock doors, pet animals tagging, share photos, videos, and other information, etc. To ensure interoperability, a classification has been established for NFC tags by NFC-Forum that provides necessary specifications between different tag providers and the manufacturers of devices. Currently, there are five different types of NFC tags, depending on storage capacity, data transfer rate and read/write ability [1].

#### **6.1 Type 1 NFC tags**

Type 1 tags are based on standard ISO14443A with a memory of 96 bytes, expandable up to 2 Kbytes. The rate of data transfer is 106 Kbps and type 1 NFC tags have read/re-write capability.

#### **6.2 Type 2 NFC tags**

Like Type 1 tags, Type 2 tags are also based on ISO 14443A standard. It has a memory of 48 bytes, expandable up to 2 Kbytes. The rate of data transfer is 106 Kbps and type 2 NFC tags have read/re-write capability.

### **6.3 Type 3 NFC tags**

Type 3 tags are Japanese Sony FeliCa standard (JIS X 6319–4). It has more memory and faster data transfer speed as compare to type 1 & 2 tags. The memory is 2 Kbyte, expandable up to 1 Mbyte with a transfer rate of 212 Kbps.

#### **6.4 Type 4 NFC tags**

Type 4 tags work on both ISO 14443 A & B communications. These are manufactured either in read only or read/re-write modes. Unlike other tags, a user cannot decide the mode. The memory is up to 32 Kbytes and, transmission rates are high; between 106 to 424 Kbps.


**7.1 NFC mobile payments applications**

*DOI: http://dx.doi.org/10.5772/intechopen.96345*

**Figure 10.**

**109**

*location [69].*

With the technological advancement in the last decade, NFC enabled mobile devices are changing the way users receive data, make payments, and exchange information across devices all over the world. The advanced innovation has already been in use in Europe, Asia and North America because of powerful impact of influential mobile network operators (MNOs) in these parts of the world [60]. Different technologies such as RFID, contactless smart card, NFC, short message service (SMS), unstructured supplementary service data (USSD), wireless application protocol (WAP), interactive voice response (IVR), and so on, all contributed in the success of mobile payments. Presently, the integration of NFC technology in contactless mobile payments led to a tap-and-go tasks. In NFC enabled device, user needs to just touch or present phone to NFC enabled device and transfer or share data without any physical connection. For mobile payments, NFC has been set to be compatible with android, windows, and iOS operating system smartphones. Presently, there are many phones which are NFC compatible such as Samsung's Galaxy Series, Google's Nexus Series, and the iPhone. Some of the NFC payment applications for tap-and-go are Google Pay, Apple Pay, Android Pay, PayPal, Samsung Pay, Square Wallet, LifeLock Wallet and Visa payWave. NFC enabled mobile payment is reducing the need for physical form of payment between consumer and merchants. For example, mobile point of sale (mPOS) units are providing wireless devices to replace traditional cash registers and sale terminals [61]. These units are wire free and easy to install, for example, customers can buy apple products without going to cashier using mPOS device. Social shopping and, mobile wallets are some other examples of mobile payments. According to a recent report from Technavio, the global mobile payment market size is expected to grow at a CAGR (Compound Annual Growth Rate) of close to 36% by the end of 2021. A report from GATE Mobile Wallet Trends (Global Acceptance Transactions Engine) also highlighted that the number of mobile payment users were close to 2.1 billion in 2019 [62]. Some of the related work in mobile payment applications are utilization of electronic vouchers using offline NFC payment service [63], payment authorization process using secured system built on a service oriented architecture (SOA) [64], secure end-to-end NFC based mobile payments protocol for security purpose [65], software card emulation in NFC based contactless smart card system for security [66], and design and initial evaluation of a touch based remote grocery shopping process [67, 68]. **Figure 10** depicts the NFC payment transfer using mobile phone, the credit card transaction with virtual card stored in a distant location [69].

*Near-Field Communications (NFC) for Wireless Power Transfer (WPT): An Overview*

*NFC payment process using mobile phone; credit card transaction process with virtual card stored in a distant*

#### **Table 5.**

*Summary of five different types of NFC tags [1, 54].*

#### **6.5 Type 5 NFC tags**

NFC forum released type 5 tags recently in 2015 that is the newest NFC tag. It is based on ISO 15693. It has working range up to 1.5 m that allows the communication with RFID tags.

There are many factors, which decide the type of NFC tag used for a particular application, such as the type of the application, memory and transmission rate requirements, working distance, and cost involved, etc. Normally, an App needs to be installed on NFC devices, smart phone, or smart watch to use the NFC tags (e.g, Apple Pay and Google Pay for payments). In 2019, Ahold Delhaize, an European super market giant, enables its shelves with NFC-enabled electronics labels that allows shoppers to obtain detailed information of the product and add items to their cart for self-checkout using smart phones [57]. In 2020, Apple recently launched a new feature in its IOS operating system, "App Clip" that allows only clips/snippets of an App to do the communications with NFC tags without downloading the whole App [58]. **Table 5** summarizes the various features like standards, memory, data transmission rate, and so on, of five types of NFC tags along with their typical uses [1].

Apart from these five types of tags, there is a Type 6 NFC tags that are based on ISO 15693-3 standards and used to store NDEF messages or applications focused on identification cards [54]. It has memory capacity of 8 Kbytes and data transfer rate of 26.48 Kbps. The newly emerged 3-D printing technology has been exploited to develop new type of tags (e.g., Kovio's NFC Barcodes) [59]. New material and printing technologies can open endless opportunities in the area of NFC communications. In the last decade, there is dramatic increase in smart phones and tablets enabled with NFC function.
