Missing Tag Identification Protocol Research Articles

A Collision Reconciling-Based B-Ary Tree-Splitting Missing Tag Identification Protocol

A Collision Reconciling-Based <i>B</i>-Ary Tree-Splitting Missing Tag Identification Protocol

An Efficient Missing Tag Identification Approach in RFID Collisions

Radio frequency identification technology has been widely used to verify the presence of items in many applications such as warehouse management and supply chain logistics. In these applications, the challenge of how to timely identify the missing tags (namely tag searching or missing tag identification) is a key focus. Existing missing tag identification solutions have not achieved their full potentials because collision slots have not been well explored. In this paper, we propose an approach named collision resolving based missing tag identification (CR-MTI) to break through the performance bottleneck of existing missing tag identification protocols. In CR-MTI, multiple tags are allowed to respond with different binary strings in a collision slot. Then, the reader can verify them together by using the bit tracking technology and particularly designed string, thereby significantly improve the time efficiency. CR-MTI also reduces the number of messages transmitted by the reader using customized coding. We further explore the optimal parameter settings to maximize the performance of our proposed CR-MTI. Extensive simulation results show that our proposed CR-MTI outperforms prior art in terms of time efficiency, total executive time and communication complexity.

Efficient collision-slot utilization for missing tags identification in RFID system

Radio Frequency Identification (RFID) technology has become one of the most promising building blocks in future IoT-enabled applications, including supply chain management, intelligent logistics, inventory control, etc.. This paper studies the fundamental problem of completely identifying missing tags in RFID systems. The most important measure for missing tag identification is to minimize the execution time. Most of the existing missing tag identification schemes compare the singleton slot in the expected mapping vector with the actual mapping vector observed by a reader to determine whether the corresponding tag is missing or not. However, they are of low efficiency because the useless collision slots account for a large proportion of the slots in a time frame. This paper proposes a Collision Unfolding-based Missing tag Identification (CUMI) protocol, which applies a novel indicator vector and Manchester coding techniques for transforming parts of abandoned collision-slots into valuable slots, thereby the utilization of slots in a time frame gets a promotion. However, CUMI requires transmitting long indicator vectors to tags, which incurs too much communication overhead. To address this problem, we propose an Enhanced Collision Unfolding-based Missing tag Identification (ECUMI) protocol to further compress the length of indicator vectors at the expense of longer tag responses. Throughout the simulation, we find that ECUMI has a higher time efficiency in missing tag identification than CUMI does. Extensive simulation results reveal that CUMI and ECUMI outperform the state-of-the-art missing tag identification protocols by at least 1.02× and 1.8× in the single-reader scenario, respectively.

Efficient and accurate identification of missing tags for large-scale dynamic RFID systems

The future real-world applications is bound up with Radio frequency identification (RFID) technology as it develops dramatically fast, especially in the field of warehouse management and inventory control, etc. In such applications, identifying missing tags to determine which goods are missing is an important issue. However, since only static scenarios with no new tag movement are considered, existing missing tag identification protocols hardly work well in more common dynamic scenarios where there are tags entering the system or missing frequently. In highly dynamic RFID systems, identifying missing tags becomes more challenge under the interference of unknown tags. Existing methods suppress this interference by filtering unknown tags, which is time-consuming and inefficient. In this paper, for high dynamic RFID systems, we propose an efficiently and accurately protocol HDMI to identify missing tags. By combining the reply slot location of the tags and the reply bits, HDMI identifies missing tags and filters the unknown tags simultaneously, which maximizes the slot utilization. We also optimize the setting of key parameters to reduce execution time while ensuring recognition accuracy. Simulation results show that, compared with state-of-art protocols, HDMI has a higher accuracy rate and better time efficiency in identifying missing tags.

Time-efficient Missing Tag Identification in an Open RFID System

Radio Frequency IDentification (RFID) technology has been widely used in missing tag identification to reduce the economic loss caused by theft. Although many advanced works have been proposed, they cannot work properly in an open RFID system with unexpected tags. That is because the unexpected tags may reply to the reader when it is the missing tags’ turn, such that the replies are mistakenly treated as the missing tags’, leading to failure to detect the missing tags. To solve the problem, this article proposes an order-based missing tag identification protocol (OMTI) that efficiently identifies all missing tags even with the presence of unexpected tags. The key of OMTI is that we dynamically assign each tag an exclusive slot rather than use random hashes in traditional design. Namely, OMTI off-line serializes all known tags in advance by assigning each of them a unique and continuous slot, on-line identifies missing tags by checking tags’ responses in each slot, and dynamically updates the slot assignment to ensure the high efficiency of the next execution. Besides, we enhance OMTI to make it embrace newly added tags and spread to the multi-reader case from the single one. The simulation results demonstrate that OMTI can significantly reduce the identification time compared to the state-of-the-art.

Efficient missing tag identification in blocker-enabled RFID systems

Due to limited on-chip resources, RFID tags may blindly respond to any readers authorized or not, leading to privacy leakage when sensitive data are exposed. A feasible solution to this problem is deploying blocker tags that emulate and behave like the genuine tags. With this deployment, there is always a virtual tag produced by the blocker tag that responds to the reader when the genuine tag to be protected replies, resulting in irreconcilable collisions and thus preventing privacy-leakage. This paper studies the problem of missing tag identification in blocker-enabled RFID systems. Unlike existing work, the reader in this problem will always get the responses from blocker tags even the genuine tags are lost, which makes the existing solutions unavailable. To address this problem, we propose three efficient protocols. The first is a group-based protocol that splits the entire tag set into three subsets and separately deals with each of them in different ways. The second protocol is called collision-reconciled protocol that turns some useless collision slots into useful singleton slots, increasing slot availability and thereby reducing the execution time. The third protocol is a concurrent missing tag identification protocol that improves the time efficiency of missing-event detection by running grouping and missing identification in parallel rather than in sequence. Theoretical analyses and extensive simulations show that our protocols are far superior to benchmark. For example, our best protocol can improve the identification efficiency by a factor of 6.

Efficiently and Completely Identifying Missing Key Tags for Anonymous RFID Systems

Radio frequency identification (RFID) systems can be applied to efficiently identify the missing items by attaching them with tags. Prior missing tag identification protocols concentrated on identifying all of the tags. However, there may be some scenarios in which we just care about the key tags instead of all tags, making it inefficient to merely identify the missing key tags due to the interference of replies from the ordinary tags (i.e., nonkey tags). In this paper, we propose to investigate the problem of efficiently and completely identifying the missing key tags for anonymous RFID systems in which the tag privacy is required to be well protected. First, we propose a vector-based missing key tag identification protocol called VEKI. Then we propose an improved protocol called iVEKI, which consists of two phases: 1) ordinary tag deactivation and 2) missing key tag identification. The parameters of the proposed VEKI and iVEKI protocols are theoretically optimized to maximize the time efficiency. Finally, we conduct extensive simulations to evaluate the proposed VEKI and iVEKI protocols and the simulation results illustrate that they outperform other existing protocols in terms of execution time.

Efficient and Reliable Missing Tag Identification for Large-Scale RFID Systems With Unknown Tags

Radio frequency identification (RFID), which promotes the rapid development of Internet of Things (IoT), has been an emerging technology and widely deployed in various applications such as warehouse management, supply chain management, and social networks. In such applications, objects can be efficiently managed by attaching them with low-cost RFID tags and carefully monitoring them. The missing objects, therefore, can be identified by the readers in the RFID system. Most of prior missing tag identification protocols consider the ideal scenario that all the tags’ IDs are known to the reader, which ignore that some tags with unknown IDs, called unknown tags, may be present in the system. In this paper, we investigate the problem of efficiently identifying the missing tags with a predefined reliability for large-scale RFID systems with unknown tags. We first propose a basic efficient and reliable missing tag identification protocol called B-ERMI. Then we propose an enhanced protocol called E-ERMI to further improve the efficiency. The parameters of our proposed ERMI protocols are optimized to minimize the execution time. We also conduct extensive simulations to evaluate the proposed ERMI protocols and the simulation results illustrate that the ERMI protocols outperform other existing ones.

Fast temporal continuous scanning in RFID systems

This paper studies the problem of temporal continuous scanning for large-scale RFID systems, which is an essential operation to keep the inventory up-to-date. The existing solutions need to execute unknown and missing tag identification protocols separately, which are of low time-efficiency because the unknown tags disturb the identification of missing tags and vice versa. To this end, we design a Fast Continuous Scanning (FCS) protocol based on the proposed multiple categories filter which can detect unknown tags and skip the empty and collision slots for improving the efficiency of missing tag identification. FCS is faster than the prior methods because the proposed filter is helpful to decreasing the interference between unknown and missing tags. We also investigate the optimization of the involved parameters to minimize the execution time. Extensive simulation results demonstrate that the proposed protocol outperforms the state-of-the-art solutions by saving 39% ∼ 58.5% of the execution time.

Identifying the Missing Tags in Categorized RFID Systems

RFID is a practical technology that supports extensive applications such as warehouse management, asset tracking, and transportation and logistics. Identifying the missing tags in categorized RFID systems is of practical importance for a variety of applications but is not yet thoroughly investigated. Traditional missing tag identification approaches can not solve the problem efficiently because they do not distinguish categories, leading to long scanning time and high energy consumption. To achieve time and energy efficiency, this paper proposes three protocols. First, we formally formulate the problem of missing tag identification in categorized RFID systems. And then a compact structure is proposed to active tags in protocols which carries a large volume aggregated tag ID information. To further improve the utilization rate of a frame, we design a rehash scheme to change empty slots and collision slots into singleton slots. We evaluate the performance of our protocols with extensive simulations. Compared with the physical-layer missing tag identification protocol (P-MTI), which is the state-of-the-art missing tag identification technology, our best protocol reduces the execution time up to 99.8%.