International Journal

on Marine Navigation

and Safety of Sea Transportation

Volume 2

Number 1

March 2008

Smart Container Security – the E-seal with RFID

Technology

Jin Zhang, Ya-qing Liu, Chun-yan Yu & Cui-fen Zhang

Dalian Maritime University, Dalian, China

ABSTRACT: In order to protect cargo from damage, theft, and terrorist threats, business and government turn

to wireless sensors and RFID tags, and tradition container is replaced by smart container. In this paper, the

basic technical features of RFID systems are described and linked to the practical applications. This paper will

also determine how the technologies perform in the real-world operational environments and evaluate the

various trade-offs that exist with E-seal design.

1 BACKGROUND

Cargo seals are more common in international trade

than for domestic shipments. This reflects the

historical and continuing importance of Customs

duties and cross-border smuggling. Manual cargo

seals have long been part of good security practice.

Their principal purpose is to assure carriers,

beneficial owners of cargo.

Manual seals vary widely in the degree of

protection they offer. Many factors affect protection,

including the design, materials, and construction of

the locking device, and the design and materials in

the hasp, bolt, or cable. The trade abounds with tales

of popular manual seal designs that have been

copied with cheap materials. There are no

international standards for manual seals.

Good seal practices improve the odds but cannot

guarantee shipment integrity. Clever miscreants can

defeat seals in numerous ways, such as cutting holes

in the side or top of a container and then repairing it.

However, the effectiveness of seal programs seems

more affected by poor practices than by unusually

skillful criminals.

2 SMART CONTAINER

Cargo container with smart systems alters globe

network in real time about security beaches. The

smart system is open, flexible and modular in

design. This will enable users to configure other

sensors or automatic identification technologies in

combinations applicable to their security or cargo

management needs. Other container sensors can

include hazardous chemical detection and various

physical parameters including temperature, light,

vibration, shock, atmospheric pressure and so on.

3 ELECTRONIC CONTAINER SEAL (E-SEAL)

E-seal ensure that ever-increasing cargo loads also

have far greater protection. These seals, combining

robust mechanical parts with sophisticated sensors,

deliver a highly cost-effective solution for the cargo

industry. An E-Seal is a radio frequency device that

transmits container information as it passes a reader

device, and issues alerts and error conditions if the

container has been tampered with or damaged. E-

Seals serve both commercial and security interests

by tracking commercial container shipments from

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their point of origin, while en route, and to their final

destination and point of customs clearance.

3.1 E-seal technology

E-seals marry manual seal elements with electronic

components to measure seal integrity, store data,

and provide communications. Some designs use

infrared signals and others use direct contact

communications technologies, but radio frequency

identification (RFID) is the most common choice.

Most e-seal designs automate the essential functions

of seal checking and reporting in order to remove

human intervention [1].

RFID has long been touted as the future of

logistics for all companies by allowing retailers and

suppliers to track goods throughout the supply chain.

Global logistics company Schenker is testing the use

of radio frequency identification (RFID) technology

to track containers used for overseas shipments.

4 RFID SEAL

RFID is the system technology that recognizes a

human or material by radio information communica-

tion and writes additional information through the

media of a card/tag that is built-in IC chip or

resonance material.

Fig. 1. RFID seal

4.1 System configuration

The purpose of the system is to communicate

data between informational medium (that is called

“RF tag”, “Transponder” of the shape of the

card/tag) and an interrogator (that is called “Reader”,

“Interrogator”) by the electric wave.

4.2 Features and Classification

Recognizable from a distance; Recognizable through

an obstacle; Reading two or more tags

simultaneously is possible; Writing additional

information is also possible; RF tag is reusable.

There are two main types of RFID tags and seals,

passive and active.

Passive seals do not initiate transmissions-they

respond when activated by the energy in the signal

from a reader. Interrogated by a reader, a passive

seal can identify itself by reporting its “license plate”

number, analogous to a standard bar code. The tag

can also perform processes, such as testing the

integrity of a seal. The beauty of a battery-free

passive seal is that it can be a simple, inexpensive,

and disposable device. Passive RFID seals can

carry batteries for either or both of two purposes.

The first is to aid communication by boosting the

strength of the reflective signal back to the reader.

This capability need not add much cost. The second

purpose is to provide power so functions can be

performed out of the range of readers [2].

Active seals can initiate transmissions as well as

respond to interrogation. All active tags and seals

require on-board power, which generally means a

battery.

All active RFID electronic seals on or

approaching the market monitor seal integrity on a

near- -continuous basis, and most capture the time

of tampering and write it to an on-board log. Some

can accept GPS and sensor inputs, and some

can provide live “mayday” tampering reports as the

events happen, mostly within specially equipped

terminals.

Passive vs active RFID seals. One may look at the

trade-offs between these technologies from

theoretical and practical perspectives. Theoretically,

the only difference between passive and active tags

and seals is the ability to initiate communications

from the tag-distinction that means passive RFID

tags could not initiate mayday calls. However, a

designer could add on-board power to a passive tag,

match other functionality and, setting aside

regulatory, safety, and cost issues, increase read

range and directional flexibility by increasing power

and adding antennas.

4.3 Standards and Frequencies [3], [4]

Adoption of RFID in supply chain and security

applications is hampered by a lack of standards and

by what some call “the frequency wars”. The two

issues are interrelated.Standards for electronic

seals address technical protocols, interfaces, and

frequencies. There are three related items.

− ISO 10374 is the existing voluntary standard for

RFID automatic identification of freight

containers. It is a dual frequency passive read- -

only standard that includes 850-950 and 2400-

2500 MHz. Globally, only two carriers use these

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tags, one primarily on chassis and the other on

chassis, ocean containers, and many dray trucks.

− ISO 18185 is a Draft International Standard for

electronic container seals. It includes passive and

active protocols, enabling both simple low cost

and more robust seals. The active protocols have

been the focal point for “the frequency wars”

in terms of freight containers.

− ISO 23359 is a New Work Item for read/write

RFID for freight containers. Work started on this

project in June 2002, and it seems likely to build

closely on the draft seal standard.

Frequency choice begins with technical

performance but includes political and regulatory

issues. In crowded freight-oriented environments

such as warehouses and terminals, the most effective

frequencies appear to be between 100 and 1000

MHz. Frequencies below 100 MHz lose range

rapidly because of inductive coupling or noise from

electrical coupling. Frequencies above 1000 MHz,

with shorter wavelengths, cannot wrap or diffract

around objects such as vehicles and freight

containers-they become more line-of-sight and

subject to blind spots.

5 LOOKING AHEAD

Container shipping is a critical component of global

trade: about 90% of global trade is transported in

cargo containers. Globalization and market

deregulation have also led to advances in security

devices and instruments and their strategic

integration within the logistics sector. The market

for E-seal that may improve both freight

transportation security and productivity is in its early

stages. We will become a big winner of market in

development through relatively early stages of use.

REFERENCES

1. Le-Pong Chin Chia-Lin Wu; The Role of Electronic

Container Seal (E-Seal) with RFID Technology in the

Container Security Initiatives”; MEMS, NANO and Smart

Systems, 2004. ICMENS 2004. Proceedings. 2004

International Conference on Aug. 2004, P：116-120.

2. HU Jianyun，HE Yan，MIN Hao; “Design and Analysis

of Analog Front-End of Passive RFID Transponders”;

CHINESE JOURNAL OF SEMICONDUCTORS 2006

Vol. 27, No. 6, P.999-1005.

3. International standard ISO/IEC 14443-1,-2,-3, International

Standardization Organization, April 2003.

4. Jung-Hyun Cho, et; ”An analog front-end IP for 13.56 MHz

RFID interrogators”; Proceedings of the 2005 conference

on Asia South Pacific design automation 2005, p. 1208- -

1211.