Guidelines
on
Shipboard Wireless LAN Systems
November 2009
NIPPON KAIJI KYOKAI
Guidelines on Shipboard Wireless LAN System
Copyright ⓒ 2009
All right reserved
No part of this document may be reproduced in any from, or transmitted by
any means, or otherwise, without prior written permission from the Society,
For NIPPON KAIJI KYOKAI,
Administration Center, 4-7 Kioi-cho, Chiyoda-ku, Tokyo 102-8567 Japan.
Introduction
Introduction
Demands for reductions in crew members and greater sophistication of equipment
fitted onboard ship started from the eighties, at which time shipboard LAN systems
began to be proposed for safe operation of ships. At that time, voyage data and
machinery data were collected and integrated, and these data were made usable from
control spaces and accommodation spaces. In recent years, the requirement for
shipboard LAN systems has been growing with the use of network systems between
ship and shore as a result increased use of satellite communications equipment
(IMMARSAT) and temperature monitoring of reefer containers, in addition to the
functions mentioned above. The diffusion of shipboard LAN systems has been
progressing, especially as more sophisticated systemization of operations has become
required in research ships and special purpose/survey ships.
The basis of the shipboard LAN systems mentioned above is the wired LAN.
Diffusion of wireless LAN systems onboard ships lags in comparison with wireless
LAN systems used on shore.
The reasons are as follows:
1. Radio wave propagation characteristics are difficult to predict onboard ship
because of the enclosure of all spaces by steel plates.
2. Interaction, interference and other hindrances to wave characteristics observed
on shore may also occur onboard ship.
3. Risks associated with eavesdropping and other security concerns exist.
4. Restrictions on the use of radio waves in various countries are not always clear
nor consistent.
However, many commercial products such as wireless IP phones, wireless cameras
and wireless personal computers are already available on the market. If
standardization of wireless LAN construction and infrastructure are established,
wiring between equipment will not be necessary, and systems using wireless LAN
terminals can be easily installed and gain widespread use very quickly.
Considering applications to ships, the adoption of wireless LAN systems is likely
to result in reduced man-hours originally required for laying electric wiring for
shipbuilders. For shipowners too, advantages are many in respect of replacement of
equipment, future expandability (scalability), and greater compatibility with varied
applications. As is the case on shore, the intention to make use of the convenience
afforded by wireless LAN systems on ships is gradually gaining ground.
7
Introduction
In the light of this background, systems with high expandability using wireless
LAN have been proposed in recent years.
On the other hand, rules for wireless LAN systems do not exist in IACS nor in the
existing Rules for the Survey and Construction of Steel Ships (hereafter referred to as
“the Rules”) of ClassNK. To respond to the wishes of shipowners and shipbuilders
considering the installation of wireless LAN systems onboard ships, and to establish
basic design and system requirements for classification so that the relevant systems
can be provided more consistently and effectively onboard ships, ClassNK has
prepared these “Guidelines on the Installation of Shipboard Wireless LAN Systems”
as a general guidance for installing wireless LAN systems onboard ships.
The authors would consider themselves honored if these guidelines prove to be a valuable
reference for the provision of wireless LAN systems onboard ships and contribute to concerned
personnel.
7
Preface
Preface
These guidelines have been prepared as a reference for wireless LAN systems to be fitted
onboard ships. A summary of the guidelines is given below.
In section 1, the advantages and disadvantages of wireless LAN is explained in comparison to
wired LAN systems from a technical viewpoint.
In section 2, wireless LAN systems to which the guidelines apply are defined.
As ClassNK does not have experience in dealing with ships fitted with shipboard wireless LAN
systems, these guidelines are to apply to communications and installations to which class
requirements do not apply. When reliability of wireless LAN equipment and systems becomes fully
verified in the future, the guidelines will apply to communications and equipment which are
designated as important use in the Rules at the next step. The guidelines will be a base for
regularization of Classification Rules in that case.
In section 3, a brief explanation is given about the main terms appearing in the guidelines.
Explanation on other terms of wireless LAN systems are given in the glossary of terms at the end of
the guidelines.
In section 4, rules and standards are introduced to assist equipment manufacturers and designers
at shipyards. It is expected that requirements of a ship’s flag state and those of the country to which
the ship calls will not necessarily be the same. Frequency bands, communication systems, antenna
power, etc. deemed acceptable for use today are listed in table form. Frequencies and outputs
assigned in foreign countries are also given for future use of foreign made products.
It is recommended that ships that are likely to call in Japanese ports should comply with
Japanese specifications, in principle. This will likely ensure compatibility in foreign ports also.
In section 5, requirements for wireless LAN equipment are described. The main points of these
requirements are those for EMC and vibration. Attention must be paid to those points when
equipment made for shore use is installed onboard ships. In this section, it is also explained that
requirements for equipment described in this section comply with the minimum requirements of the
Classification Rules even if the requirements are those for equipment of un-important use.
In section 6, system configuration and connection issues are explained to help readers gain a
better understanding of basic concepts based on the matters mentioned above.
In section 7, operation tests to be carried out by shipbuilders during and after the installation of
LAN systems and equipment, as well as performance tests required by ClassNK, are described.
In section 8, maintenance is described with examples of network management for a system using
a control server.
In section 9, the Crew Safety Management Support System is introduced as an application
example of shipboard wireless LAN systems which was demonstrated at Sea Japan Tokyo 2008 and
the Imabari Maritime Fair in 2009.
7
Preface
A recent news article reported that a certain ocean-going passenger ship company had expanded
their shipboard services by commencing Internet connection service with the shipboard wireless
LAN system and mobile telephones onboard ship. In Japan, a system has been developed and
marketed, in which a shipboard surveillance robot with an infrared temperature sensor and a CCD
camera on a wireless LAN system transmits fire detection data to a wired LAN.
A crew member can call his or her family from any location onboard the ship by connecting a
wireless IP phone to his or her home via satellite. The Master can also easily find the location of
any crew member onboard the ship via this system. These features effectively improve the
seamen’s working environment.
In utilizing radio communications on wireless LAN systems, reliability of the communications
needs to be fully evaluated by applying it firstly to the communications between devices of
un-important use. On the basis of this evaluation, step-by-step introduction needs to be considered
regarding expanding applications of the communications to devices of important use in the future.
In utilizing wireless LAN systems for the communications between devices of important use, as
well as redundancies, such as the back-up arrangement of power supplies, should be taken into
account depending on the importance of the role of the wireless LAN system.
Application range is so wide that further use may be expected when systems for devices of
important use are developed.
A working group which studies shipboard wireless LAN systems has been set up in IACS. This
working group is tasked with the development of unified requirements for a system based on
IEEE802.11 with a schedule to make requirements for radio inter-communications between devices
after 2010.
The authors acknowledge with thanks the guidance received from various personnel concerning
wireless technical standards, technical terms, and wireless LAN model tests.
7
Preface
Table of Contents
1. What is LAN? ................................................................................................................... 1
2. Application ....................................................................................................................... 2
3. Explanation of terms......................................................................................................... 3
4. Standards and rules related to wireless LAN systems......................................................... 4
4.1 Wireless LAN standards .............................................................................................. 4
4.2 Japanese rules (technical standards) ............................................................................ 4
4.3 Certification system for technical regulations for compliance of radio equipment in
Japan................................................................................................................................ 7
4.4 Using wireless LAN equipment onboard Japanese flag ships ........................................ 7
4.5 Frequencies and outputs allowed in each country......................................................... 7
4.6 Restrictions on the use of radio waves in port............................................................... 8
4.7 Using wireless LAN equipment onboard ships of foreign flags...................................... 8
5. Requirements applicable to wireless LAN.......................................................................... 9
5.1 Requirements for specifications ................................................................................... 9
5.1.1 Frequency ............................................................................................................. 9
5.1.2 Wireless LAN access points and maximum output of wireless terminals................. 9
5.1.3 Security................................................................................................................. 9
5.2 Requirements of equipment ......................................................................................... 9
5.2.1 Electromagnetic compatibility of equipment (display of CE mark) ........................ 9
5.2.2 Electromagnetic compatibility (EMC) of equipment on the bridge ......................... 9
5.2.3 Operating voltage.................................................................................................. 9
5.2.4 Vibration resistance............................................................................................... 9
5.2.5 Ambient temperature conditions............................................................................ 9
5.3 Requirements for installation....................................................................................... 9
5.3.1 Locations for installing equipment......................................................................... 9
5.3.2 Precautions during installation ............................................................................ 10
5.3.3 Measures against vibration.................................................................................. 10
5.3.4 Power source ....................................................................................................... 10
5.3.5 LAN cable outfitting procedures.......................................................................... 10
6. Basic system design of wireless LAN................................................................................ 11
6.1 Basic configuration.................................................................................................... 11
6.2 Design of wireless LAN systems ................................................................................. 13
6.3 Examples of connection of wireless LAN shipboard equipment .................................. 14
7. Procedures for onboard testing ....................................................................................... 15
8. Maintenance ................................................................................................................... 16
9. Advantages and application examples of wireless LAN systems ....................................... 17
9.1 Application examples of wireless LAN systems........................................................... 17
9.2 Examples of using wireless LAN systems.................................................................... 18
Appendix
App. - 1. Glossary of terms ............................................................................................... 23
7
7
1. What is LAN?
1. What is LAN?
Generally, LAN (Local Area Network) may be of two types: wired LAN constructed from twisted
pair cables, coaxial cables, optical fibers, etc., and wireless LAN constructed from wireless
connections using radio waves. LAN has developed onshore as a data communication network for
sharing and processing data by integrating personal computers and printers in specific areas such as
offices, research institutes, factories or universities.
Wireless LAN made its appearance in the early half of the nineties, and communication standards
for such systems were standardized globally in the latter half of the nineties. Since cables and wiring
are not required up to the terminal equipment in wireless LAN, it was initially used in offices and the
like where office layout needed to be changed frequently. After standardization of communication
standards, wireless LAN equipment has been installed in public areas such as train stations, airports
and hotels, as shown in Fig. 1, and the public Internet environment has developed rapidly, as well.
In this way, wireless LAN has spread rapidly on land in various fields; along with this spread, the
prices of peripheral equipment and terminals have dropped dramatically. This has also led to the
spread of such systems in ordinary households, too. Naturally, this kind of diffusion on land is likely
to happen in the shipping field, too.
Table 1 shows a comparison of the general advantages and disadvantages of wired and wireless
LAN systems.
Table 1 Advantages and Disadvantages of Wired and Wireless LAN Systems
Wired LAN Wireless LAN
Advantages * Less external interference, stable * No cables required.
communications. * Multiple terminals can be connected and easily
* High communication speeds (mainly 1,000 increased.
Mbps). * Since wiring is absent, terminals can be moved
* Comparatively safe considering security easily.
aspects. * Place need not be selected; information can be
transmitted while on the move.
Disadvantages * Wiring is necessary for connecting each * Sometimes communications are not stable,
equipment used in the LAN. depending on the environment.
* The number of units that can be connected * Communication speed is low compared to wired
is limited by the number of ports that can be LAN.
connected. * Greater considerations need to be given to security
* Limitations in the places where LAN can be aspects of wireless LAN.
used. * Settings specific to wireless connections need to be
made.
Fig. 1 Example of installation of public wireless LAN (in the premises of a Tokyo subway station).
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2. Application
2. Application
These guidelines give a general description of standards related to the specifications, design, and
installation of wireless LAN systems installed onboard ships.
These guidelines are applicable to communications other than those for important services
prescribed in the Classification Rules and those between navigational equipment.
For this reason, unless specifically indicated otherwise, classification requirements do not apply
to requirements described in these guidelines.
These guidelines do not impose any restrictions on the selection of hardware, materials, or
processes for specific items.
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3. Explanation of terms
3. Explanation of terms
The meanings of the terms used in these guidelines are explained in this section. Details of these
terms and other related technical terms are given in the glossary of terms in the Appendix of this
document.
3.1 Access point
A radio switching device connecting the wireless terminal to the network.
3.2 Network switch
A network switching hub. Also called a switching hub.
3.3 Wireless terminal
The collective name for wireless personal computer, wireless IP phone, wireless camera, etc.
3.4 Control server
A server with functions for maintaining and controlling wireless LAN and wireless terminals.
3.5 LAN cable
Cable for wiring used in the network.
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4. Standards and rules related to wireless LAN
4. Standards and rules related to wireless LAN
4.1 Wireless LAN standards
The wireless LAN being used at present follow various standards that have been established and
for the most part standardized by the IEEE802 Committee. The IEEE802 Committee was set up in
February 1980 by the Institute of Electrical and Electronic Engineers (IEEE) with the aim of
standardizing LANMAN (Metropolitan Area Networks). The group that discusses wireless LAN
in the IEEE802 Committee is referred to as 802.11. The important wireless LAN standards
established by IEEE802.11 are shown in the table below.
Table 4.1 Wireless LAN Standards
Remarks (for Japan
Standard Established in Frequency band Rated speed
only)
IEEE 802.11 1997 2.4 to 2.5 GHz 2 Mbps License not required
IEEE 802.11b October 1999 2.4 to 2.5 GHz 11 Mbps License not required
5.15 to 5.35 GHz:
License not required if
used indoors
5.15 to 5.35 GHz
IEEE 802.11a October 1999 54 Mbps
5.47 to 5.725 GHz;
5.47 to 5.725 GHz
License not required
regardless of whether
indoors or outdoors
IEEE 802.11g June 2003 2.4 to 2.5 GHz 54 Mbps License not required
IEEE 802.11n September 2009 2.4 GHz /5 GHz 300 Mbps
4.2 Japanese rules (technical standards)
Wireless LAN standards are established by IEEE802.11, and each country establishes its own
rules based on these standards.
The main technical standards related to IEEE802.11 (2.4 GHz band and 5.2 GHz band) in Japan
are as shown in Table 4.2.
For details of the technical standards, refer to the Japanese “Ordinance Regulating Radio
Equipment,”* Article 49.20 (radio equipment for use in radio stations of a low-power data
communication system).
* For the ordinance, please refer to the following URL on the Internet:
http://www.tele.soumu.go.jp/resource/e/equ/tech/orre.pdf
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Table 4.2 List of Main Technical Regulations of Low Power Data Communications Systems (as of October 2009)
Item Technical standard
Frequency 2400 to 2483.5 MHz 2471 to 2497 MHz 5150 to 5250 MHz 5250 to 5350 MHz 5470 to 5725 MHz
Band W52 W53 W56
1,2,3,4,5,6,7, 100, 104, 108, 112, 116, 120, 124, 128, 132, 136,
8,9,10,11,12,13 36, 40, 44, 48 (20 MHz system) 52, 56, 60, 64 (20 MHz system) 140 (20 MHz system)
One channel is regulated 14 5180, 5200, 5220, 5240 MHz 5260,5280,5300,5320 MHz 5500, 5520, 5540, 5560, 5580, 5600,
Channel Center frequency 2484 5620, 5640, 5660, 5680, 5700 MHz
from 2412 MHz at MHz
5-MHz interval for 38，46 (40MHz system) 54，62 (40MHz system) 102, 110, 118, 126, 134 (40MHz system)
center frequencies 5190, 5230 MHz 5270, 5310 MHz 5510、5550、5590、5630、5670 MHz
One-way One-way communication,
communication, simplex simplex operation system, One-way communication, simplex One-way communication, simplex One-way communication, simplex operation
Communication
operation, half-duplex half-duplex operation or operation system, half-duplex operation system, half-duplex operation system, half-duplex operation
method duplex operation using
operation or duplex operation or duplex operation or duplex operation
operation spectrum spread system
Modulation (1) Orthogonal frequency
division multiplex (OFDM)
(1) DS method, OFDM method
method Direct spread (DS)
*1 (2) Amplitude modulation method,
method , or spectrum method, frequency (1) DS method, OFDM method (1) DS method, OFDM method
*2 phase modulation method, frequency
spread method hopping (FH) method (2) Other methods (2) Other methods
modulation method, pulse modulation
(2) Digital modulation other or DS+FH method
method, and their combinations
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than (1) above
4. Standards and rules related to wireless LAN
6
Frequency 6 -6 6 6 ±20×10-
±50×10- ±50×10 ±20×10- ±20×10-
Tolerance
*3
Permissible 83.5 MHz
*4 19 MHz (OFDM), 18MHz (Others) 19.7MHz (20 MHz system)
Values for 26 MHz or less 26 MHz or less Same as W52
Occupied 38 MHz(OFDM 40 MHz 38 MHz（OFDM 40 MHz system） 38 MHz（40 MHz system）
Bandwidth system)
10mW/MHz or less, OFDM
method in the 40 MHz
system is 5mW/MHz or less,
However, FH, FH+DS, DS method and OFDM method in the 20 MHz system:
FH+OFDM methods that 20 MHz method are 10mW/MHz or DS method and OFDM method DS method and OFDM method are 10 mW/MHz
Antenna power use frequencies from 2,427 10mW/MHz or less less, other methods are 10mW. 10mW/MHz or less, other methods are or less, other methods are 10mW or less
MHz to 2470.75 MHz are OFDM method in the 40 MHz system 10mW or less 40 MHz system:
3mW/MHz or less; methods is 5mW/MHz or less OFDM method is 5mW/MHz or less
other than OFDM method or
spectrum spread method are
10mW or less
Tolerance for
＋20％、－80％ ＋20％、－80％ ＋20％、－80％ ＋20％、－80％ ＋50％、－50％
antenna power
12.14 dBi or less
However, half-value
Gain of
angle θ is to be 360/A or
transmitting
less (Max. value of A is 2.14 dBi or less No regulation No regulation No regulation
antenna *5
10)
When 3 dB power reduction function provided When 3 dB power reduction function provided
Equivalent 10mW/MHz or less (20 MHz system) 50mW/MHz or less (20 MHz system)
isotropic 10mW/MHz or less (20 MHz system) 5mW/MHz or less(40 MHz system) 25mW/MHz or less (40 MHz system)
No regulation No regulation When power reduction function not available
radiated power 5mW/MHz or less(40 MHz system) When power reduction function not available
(EIRP) 5mW/MHz or less (20 MHz system) 25mW/MHz or less (20 MHz system)
2.5mW/MHz or less (40 MHz system) 12.5mW/MHz or less (40 MHz system)
Diffusion
bandwidth 500 kHz ≤ 500 kHz ≤
Diffusion rate, 5≤ 10 ≤ No regulation No regulation No regulation
Frequency ≤400 ms ≤400 ms
retention time
Radar wave
― ― No Yes Yes
detection (DFS)
Location where
Indoors and outdoors Indoors and outdoors Indoors only Indoors only Indoors and outdoors
used
*1：The number of carriers per bandwidth of 1 MHz should be 1or more.
*2：Direct spread (DS) method, frequency hopping (FH) method or DS+FH method or OFDM+FH method.
4. Standards and rules related to wireless LAN
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*3：FH method, DS+FH method or OFDM+FH method.
*4：System other than the *3 above.
*5：”A” is calculated in the form of “EIRP divided by 12.14dBi”. If the A is lower than 1, it can be regarded as 1. (Half-value angle θ: angle of the main radiation
beam of the horizontal plane and vertical plane of the transmitting antenna.)
*6：Value obtained by dividing the diffusion bandwidth by the frequency equivalent to the transmission speed of the modulation signal.
*7：The sum of the frequency retention times at arbitrary frequencies within the period obtained by multiplying the diffusivity by 0.4 seconds is 0.4 seconds or less.
4. Standards and rules related to wireless LAN
4.3 Certification system for technical regulations for compliance of radio equipment
in Japan *
The certification system for technical regulations based on the Radio Law of Japan is established
from the four methods (1) to (4) below.
(1) Technical Regulations Conformity Certification (Article 38.6 of the Radio Law)
(2) Construction Design Attestation (Article 38.24 of the Radio Law)
(3) Self-check of compliance to technical regulations (Article 38.33 of the Radio Law)
(4) Certification related to compliance assessment for registration in a foreign country (MRA
Law (*) Article 29) (*) Refer to glossary of terms
Equipment that has been certified to conform to technical regulations based on any of the
methods (1) to (4) above is affixed with the identification (technical regulation conformity mark)
shown in Fig. 4.1.
Fig. 4.1 Example of technical regulation conformity mark.
* For details of the certification system, please refer to the following URL on the Internet:
http://www.tele.soumu.go.jp/e/sys/equ/tech/index.htm
4.4 Using wireless LAN equipment on board ships of Japanese flag
Wireless LAN equipment used onboard ships of the Japanese flag are required to comply with
the technical regulations of 4.3 above, and the conformity mark is to be affixed on the equipment
regardless of whether the products are domestic or foreign made.
4.5 Frequencies and outputs allowed in each country
Table 4.3 shows the status of permitted frequencies and outputs overseas that have been
established as of October 2009.
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4. Standards and rules related to wireless LAN
Table 4.3 Frequencies and Outputs Assigned to Each Country
Wireless IEEE 802. IEEE802.
LAN 11b,g 11b IEEE 802. 11a
standards
Frequency 2400 to 2471 to 2497 5150 to 5250 to 5350 to 5470 to 5725 to 5725 to 5725 5825 to
2483.5 5250 5350 5470 5725 5825 5850 to 6425
5875
(MHz)
Japan 10mW/MHz 10mW/MHz 10mW/MHz 10mW/MHz --- 50mW/MHz --- --- --- ---
(EIRP) (EIRP) --- (EIRP) --- --- --- ---
US --- --- --- --- --- 1W --- --- ---
1W
(Txout) --- --- --- --- --- (Txout) --- --- ---
Canada 1W --- 200Mw 1W --- --- --- --- --- ---
(EIRP) (EIRP)
(Txout) --- --- --- --- --- --- ---
Europe 100mW --- 200mW 200mW --- 1W --- --- --- ---
(EIRP) --- (EIRP) (EIRP) --- (EIRP) --- --- --- ---
China 500/100 mW --- --- --- --- --- --- 2W --- ---
(EIRP)
(EIRP --- --- --- --- --- --- 500mW --- ---
depending on (Txout)
antenna gain)
Australia 100mW --- --- --- --- --- --- 4W --- ---
(EIRP) --- --- --- --- --- --- (EIRP) --- ---
India 100mW --- --- --- --- --- ---
(Txout) --- --- --- --- --- ---
Russia 100mW --- 50mW 250mW 1W 1W 1W 1W --- 1W
(Txout) --- (Txout) (Txout) (Txout) (Txout) (Txout) (Txout) --- (Txout)
* Notes
---： Not assigned
Empty column: To be assigned but not clear in terms of specific details.
4.6 Restrictions on the use of radio waves in port
Restrictions on frequencies and outputs vary in different countries. Thus careful attention must be
paid to the latest conditions of the restrictions in any countries of particular concern. Wireless LAN
equipment should not be used in a port where its use is restricted.
4.7 Using wireless LAN equipment onboard ships of foreign flags
In principle, equipment sold in Japan is to be used. However, foreign-made equipment that is not
sold in Japan can be used, if the equipment is properly attested in accordance with the Mutual
Recognition Agreement Law.
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5. Requirements applicable to wireless LAN
5. Requirements applicable to wireless LAN
5.1 Requirements for specifications
5.1.1 Frequency
Any of the following frequencies is to be used for wireless LAN systems: IEEE802.11b,g（2400
MHz to 2483.5 MHz）, IEEE802.11ｂ（2471 MHz to 2497 MHz）, IEEE802.11ａ（5150 to 5250 MHz）,
IEEE802.11ａ（5250 to 5350 MHz）, IEEE802.11ａ（5470 to 5725 MHz）.
5.1.2 Wireless LAN access points and maximum output of wireless terminals
The maximum output is to be 10mW/MHz. However, the maximum output is to be 50 mW/MHz
EIRP for IEEE802.11a of 5470~5725 MHz adopting DFS (Dynamic Frequency Selection) and TPC
(Transmitter Power Control) technologies.
5.1.3 Security
To avoid unauthorized connection by a third party or eavesdropping of wireless communications, the
use of security equivalent to WPA-PSK is recommended. WEP is not recommended since it has been
pointed out that it can be decoded within a short period of time.
5.2 Requirements of equipment
5.2.1 Electromagnetic compatibility of equipment (display of CE mark)
Since a ship is likely to enter EU waters, in principle, all equipment should be affixed with the CE
mark indicating compliance with the EU Directive on Electromagnetic Compatibility.
5.2.2 Electromagnetic compatibility (EMC) of equipment on the bridge
Access points provided on the bridge are, in principle, to have equipment that have cleared the EMC
test prescribed in IEC60945 Ed.4 for preventing interference with navigation instruments provided in
the bridge.
5.2.3 Operating voltage
Equipment that works on 100 to 220 volts AC is to be used. The equipment is to remain functional
without being cut off even during power supply variation, up to a 6% rise and 10% drop in voltage,
occurs. In case of a blackout, the equipment should be capable of having its operation restored
immediately after recovery from the blackout.
5.2.4 Vibration resistance
The vibration resistance function of the equipment should be resist to vibration at the location where
it is installed.
5.2.5 Ambient temperature conditions
To ensure correct operation of wireless LAN equipment, the requirements set forth in Part H, section
1.1.7 of the Rules are to be adhered to, unless specifically noted otherwise.
5.3 Requirements for installation
5.3.1 Locations for installing equipment
Equipment is to be installed at an adequately ventilated location so that it is not exposed to risks
of mechanical damage, nor damaged from water, steam or oil.
Moreover, if this equipment is to be installed at locations where explosive air-fuel mixture, or
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5. Requirements applicable to wireless LAN
combustible gas is likely to accumulate, then it is to be of a type approved as being explosion-proof.
5.3.2 Precautions during installation
If lamps indicating continuity and operating status are provided in the equipment, these are to be
fitted so that the status can be checked easily. Equipment provided with fuses and breakers is to be
installed so that they can be easily replaced and maintained.
5.3.3 Measures against vibration
The shipbuilder is to determine the most appropriate method for installing the equipment provided
at each access point depending on the condition of the vibrations anticipated so that the equipment
can withstand the vibrations that occur at the location where the equipment is installed. If necessary,
measures should also be adopted including the use of shock absorbing materials or securing methods
so that vibrations do not affect the equipment directly.
5.3.4 Power source
Redundancy of power supply is not required, unless specifically noted in the design
specifications.
5.3.5 LAN cable outfitting procedure
Laying, supporting, fixing, penetrating bulkheads, and connections of LAN cables are subject to
Part H of the Rules.
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6. Basic system design of wireless LAN
6. Basic system design of wireless LAN
6.1 Basic configuration
The basic equipment that constitutes a wireless LAN system is described below.
(1) Access point
(2) Network switch
(3) Wireless terminal (wireless personal computer, wireless IP camera, wireless IP telephone, etc.)
(4) Control server
(5) LAN cable
An example of the configuration of a common wireless LAN system provided onboard a ship is
shown in Fig. 6.1.
To construct a wireless LAN system, access points are installed at various locations on the ship,
and wired with LAN cables using network switches as the pivot points. The control server may be
installed in the wheel house, cargo control room, engine control room, or other suitable location.
Control server
Access Point
LAN Cable
Network switch
IEEE802.11a/b/g Wireless Terminals
Fig. 6.1 Example of the configuration of a typical wireless LAN system onboard ship.
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6. Basic system design of wireless LAN
Fig. 6.2 shows an example of access points provided in a typical onboard LAN system.
(1) Example of access point in engine room.
(2) Example of access point in accommodation space.
(3) Example of access point in acc. space corridor.
Fig. 6.2 Example of provision of access points onboard ship.
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6. Basic system design of wireless LAN
If the access point has a repeater function for relaying data between wireless terminals, the system
can be configure as shown in Fig. 6.3.
Control server
Access point
Relay by repeater function
Network switch
LAN cable
IEEE802.11a/b/g Wireless terminal
Fig. 6.3 Example of wireless LAN system with repeater function.
If the repeater function mentioned above is used, for instance, and if two access points are distant
from each other as shown in Fig. 6.4, the laying of LAN cables to the access points shown in the
figure by dotted lines is no longer required; thereby eliminating cable laying costs.
LAN cable need not be laid
LAN cable
Relay by repeater function
Fig. 6.4 Example of use of repeater function.
6.2 Design of wireless LAN
When deciding the subdivisions to which communications are to be made during design of wireless
LAN, the arrangement of access points and the selection of frequencies (standard) are to be
considered. All the requirements mentioned in Chapter 4 above should also be considered at the
same time.
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6. Basic system design of wireless LAN
6.3 Examples of connection of wireless LAN shipboard equipment
Construction of a system for transmitting data through a wireless LAN system such as voyage and
surveillance data of equipment fitted onboard the ship can be considered.
In this way, when shipboard equipment is connected to wireless LAN, measures need to be taken
to ensure that factors that generate noise and improper operation, etc., are not transmitted from the
shipboard equipment to the wireless LAN system, regardless of whether they are essential or
non-essential services. Consideration also needs to be given to ensuring that any troubles and
faults that may occur in the wireless LAN system do not affect other equipment.
Interface equipment may be installed for electrically insulating the space between the navigation
equipment or monitoring system and the wireless LAN system, as shown in Fig. 6.5, for instance.
Navigation
equipment
Wireless LAN system
Interface equipment
Monitoring
system
Fig. 6.5 Example of interface equipment.
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7. Procedures of on board test
7. Procedures of onboard testing
A functional check of the wireless LAN system is to be carried out under conditions in which it will
be normally used after the system has been installed onboard the ship.
If the wireless LAN system complies with these guidelines which limit its application to non-vital
services, the attendance of a surveyor is not necessary at confirmation tests of operation.
However, in cases where wireless LAN equipment that has not cleared the IEC60945 Ed.4 EMC
test has been installed on the bridge, it must be confirmed during sea trials that this wireless LAN
equipment does not affect navigational equipment and vice-versa.
In confirming a wireless LAN system’s operation, the individual confirmation tests should be
carried out individually with all installed radio equipment such as wireless IP telephones, wireless
PC, wireless cameras, etc. Fig. 7.1 shows examples of the confirmation testing of a wireless LAN
system onboard a ship.
(1) Example of voice test by wireless IP telephone.
(2) Example of data communication test of wireless personal computer and wireless camera.
Fig. 7.1 Examples of onboard testing of wireless LAN equipment.
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8. Maintenance
8. Maintenance
The maintenance of a shipboard wireless LAN system is to be carried out in accordance with the
instruction manual of the manufacturer for each component of the system.
Introduction of a network management system to the control server will make it possible to
always monitor the operation of equipment and contribute to maintaining and effectively managing
the operational quality of a shipboard wireless LAN system and to realize stable operation of the
system.
Fig. 8.1 shows an example of the network management system screen which displays the
operational status of a connected access point, event log, etc.
Fig. 8.1 Example of network management system screen.
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9. Advantages and Application examples of wireless LAN system
9. Advantages and examples of application of wireless LAN systems
9.1 Application examples of wireless LAN systems
Figure 9.1(2) shows an engine room monitoring system as an example application of a wireless LAN
system.
In the engine room monitoring system, surveillance cameras are installed around the main engine,
generator, incinerator, and boiler to monitor conditions of the engine room from the wheel house and
the engine control room.
To set up this engine room monitoring system as a wired system, each surveillance camera in the
engine room needs to be connected to the control panel by a coaxial cable, as shown in Fig. 9.1(1).
On the other hand, to set up the engine room monitoring system as a wireless system, wireless
surveillance cameras need not be connected by coaxial cables but with one or more access points by
radio waves, as shown in Fig. 9.1(2).
Signal wiring to each surveillance camera is not required in a wireless LAN system. This means
that, when changing the arrangement of surveillance cameras or installing an additional camera
onboard a ship in service, only power-supply wiring is required. Additional power may be supplied
from the nearest lighting power distribution board, and changes in the layout can be made with
minimum outfitting work.
Monitor Control
Panel Surveillance camera
Coaxial cable
Fig. 9.1(1) Example of configuration of a wired engine room monitoring system.
Wireless
Monitor Control surveillance camera
panel
LAN cable AC power
Network switch
Access point IEEE802.11a/b/g
Fig. 9.1.(2) Example of configuration of a wireless LAN engine room monitoring system.
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9. Advantages and Application examples of wireless LAN system
Surveillance cameras may also be used as a security measure against suspicious persons in
addition to their use of monitoring the engine room. In installing a surveillance camera to guard
against suspicious persons, the cameras are to be installed at the locations specified in the ship’s
security standards. Such locations are generally in the vicinity of the boarding gangway and the
mooring deck.
Adoption of a wireless LAN based surveillance system as a measure against suspicious persons
makes it easy for ships in service to install a surveillance system. Furthermore, it is efficient in terms
of additional installation or relocation of surveillance cameras related to the future review of security
standards.
When wireless communications between the ship and the port office at the port of call becomes
available, the video images on the surveillance camera onboard the ship can be monitored by the
port office. This feature can also contribute to the implementation of a highly sophisticated port
security system.
9.2 Examples of using wireless LAN system
The concept of the Crew Safety Management System based on the introduction of a shipboard
wireless LAN system was announced at the Sea Japan exhibition in 2008, after joint development of
the system by MITSUBISHI HEAVY INDUSTRIES, LTD. and FURUNO ELECTRIC CO., LTD.,
as a system for ships using wireless LAN.
Fig. 9.2 shows an overview of the Crew Safety Management System. The Crew Safety
Management System is a system that combines a wireless IP telephone system that enables talking
in all areas on the ship when each crew member carries a wireless IP telephone, and a wireless LAN
position data system that detects the position of the wireless IP telephones (=crew) by detecting the
connection data between the access point and the wireless IP telephone.
Management server Wireless IP phone
Crew
LAN cable
Access point
Position detecting screen
Network switch
Fig. 9.2 Example of Crew Safety Management System.
Similar to the commonly available mobile phone, voice and instant messaging (mail), image
sending and receiving functions can be used in the wireless IP phone by introducing the system
shown above. Moreover, by integrated control of position data of crewmembers onboard the ship,
the work efficiency during normal hours can be enhanced based on the position data, support for
emergency response in the event of a fire or accident becomes more effective, and overall safety of
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9. Advantages and Application examples of wireless LAN system
the ship is enhanced.
If the crew position data is recorded and saved on a hard disk or other storage media, the data will
also be useful in post-accident analyses.
At the Imabari Maritime Fair (BARI-SHIP) in 2009, the concepts of shipboard safety surveillance
data and ship-shore communications were combined with the Crew Safety Management System
mentioned above, and an expanded Crew Safety Management System (hereafter referred to as Ship
Safety Management Support System) was announced by the same companies, namely MITSUBISHI
HEAVY INDUSTRIES, LTD., and FURUNO ELECTRIC CO., LTD. Fig. 9.3 shows an overview
of the Ship Safety Management Support System. By superimposing and displaying the data obtained
from the fire control panel, which is a shipboard safety surveillance data, and the crew position data,
this system can support fire extinguishing activities and escape guidance based on the location of the
crew members when a fire occurs. Similarly, by superimposing and displaying crew position data
and door surveillance data and surveillance cameras, the location of crew members can be
instantaneously known when an abnormality is detected by the surveillance camera when the door is
opened or closed. Thus, the system is effective as a security measure against the entry of suspicious
persons during service or during cargo operations.
Mgmt server Satellite
Ship’s earth
station.
Shore office
Wireless Tag
Crew
Wireless IP phone
Interface
Ship safety surveillance. info
Fire control panel Door surv. panel Surv. camera GPS/DGPS Other surveillance
Fig. 9.3 Example of Crew Safety Management Support System.
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9. Advantages and Application examples of wireless LAN system
Furthermore, by connecting the system to satellite communications equipment such as
IMMARSAT and VSAT, surveillance camera images and status of fires, locations of crew members,
and other shipboard conditions can be easily known even from shore-based management companies.
In recent years, wireless tag is being offered as portable wireless terminal. Crew members are likely
to carry wireless tags, which has excellent portability or wireless IP telephones with voice functions.
The examples above show that operations and security measures which were not possible in the
past can be implemented by introducing new features such as crew position data.
As a case example of the above, the Safety Centre on Passenger Ships (hereinafter referred to as
the “Safety Center”) may be pointed out. Safety Centers will become mandatory onboard passenger
ships in accordance with SOLAS Chapter II-2 (effective on 1 July 2010).
The Safety Center is installed with the objective of managing emergency situations such as fires,
by collecting shipboard safety information from fire detection systems, television surveillance
systems, fire doors, and general emergency alarms, etc. The SOLAS Convention also requires a
means of communication between the Safety Center, the central control station, the navigation
bridge, the engine control room, and fire control station for fire extinguishing systems and fire
equipment lockers.
By constructing the Ship Safety Management Support System mentioned above, the collection
and distribution of information to and from each crew member becomes possible in the locations
other than those required by SOLAS.
Attachment of wireless tags to passengers and lifejackets on passenger ships can help effectively
locate passengers and crew members and assist in the provision of evacuation guidance.
The Bridge Navigational Watch Alarm System (hereinafter referred to as “BNWAS”) may be
pointed out as another case example showing expandability in the future as one of the advantages of
a wireless LAN system. BNWAS was adopted at the MSC86 in May 2009. NOTE) An example of a
wired BNWAS is shown in Fig. 9.4(1) and a wireless LAN BNWAS in Fig. 9.4(2).
NOTE : Currently, test standards IEC 62616 of BNWAS are under development at the IEC. It is not clear at
this moment whether wireless LAN systems will be adopted in the future or not.
BNWAS is required to issue an alarm outside the bridge at locations such as the Master’s, back-up
officer’s and other crew members’ locations. A control unit is provided in the bridge and buzzers as
well as buzzers with switches are provided at alarm locations. For this reason, signal lines must be
wired from the control panel in the bridge to the buzzers at each of the alarm locations, as shown in Fig.
9.4(1).
BNWAS is mandatory on existing ships. In addition to the cost of equipment, considerable cost will
be necessary for wiring work. On the other hand, if wireless LAN BNWAS becomes available, wiring
work from the bridge to each of the alarm locations becomes unnecessary by installing access points
and alarm units at each of the alarm locations shown as Fig. 9.4(2).
Furthermore, in ships where a shipboard wireless LAN system is already provided, only wiring
between the control panel and already-installed network switches is required to configure BNWAS.
Up to here, the advantages of adopting a wireless LAN system and its application examples have
been explained. With a wireless LAN system fitted onboard a ship, the ship can flexibly correspond
to expansion in installations such as convenient wireless IP telephones, surveillance cameras for use
in security measures, and mandatory installations such as BNWAS required by SOLAS regulations.
Owing to the easy expandability of the wireless LAN systems mentioned above, a number of
functions and information can be used in a wireless LAN system infrastructure, and various
applications and possibilities are expected after the introduction of such systems onboard ship in the
future.
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9. Advantages and Application examples of wireless LAN system
Marine cable
Control unit Buzzer
(bridge)
Buzzer
Buzzer with
switch
Buzzer with
switch
Fig. 9.4(1) Example of BNWAS with wiring.
Control unit Network switch
(bridge) LAN cable
Alarm unit
AC power
AC power
Fig. 9.4(2) Example of BNWAS expansion by wireless LAN.
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References
References
(1) International Telecommunication Union “Radio Regulations and its Appendix”, Denki Tsushin
Shinkokai, March 1999.
(2) “Radio Law Statutes”, Denki Tsushin Shinkokai, December 2008.
(3) "802.11 High speed wireless LAN textbook”, Editors: Hideaki Matsue, Masahiro Morikura;
Published by: Showa Mitsuhashi, Publisher: IDG Japan; IDG Information Communication
Series, 29 March 2003.
(4) “Crew Safety Management System by introducing shipboard wireless LAN", MITSUBISHI
HEAVY INDUSTRIES, LTD., FURUNO ELECTRIC CO., LTD., FURUNO SYSTEMS, SEA
JAPAN data, April 2008.
(5) The Japan Maritime Daily, “POA that enables mobile phone use”, 5 November 2008.
(6) Kaiji Press Co., Ltd.., “Development of the world’s first autonomous surveillance robot for fire
detection”, 3 April 2008.
(7) “Ship Safety Management Support System”, MITSUBISHI HEAVY INDUSTRIES, LTD.
FURUNO ELECTRIC CO., LTD., FURUNO SYSTEMS, Imabari Maritime Fair data, May
2009.
(8) “Rules for the Survey and Construction of Steel Ships and NK Guidance, Part H Electrical
Installations”, NIPPON KAIJI KYOKAI, 2009 edition.
-22-
Appendix
Appendix
App. - 1. Glossary of terms
・Bluetooth
A wireless communication technology used to communicate over a distance of a few meters; uses
radio waves in the 2.4 GHz band. The maximum transmission speed is 3 Mbps. Small-scale wireless
networks can be easily formed; therefore, this technology is used in wireless hands-free mobile
phones for connecting wireless headset, wireless headphones for music players, wireless mice for PC
and so on.
・IEEE 802.11
IEEE stand for the Institute of Electrical and Electronic Engineers, the world’s largest association
of electrical and electronic engineers in the USA. This association has a committee named 802. The
working group (WG) 11 under the umbrella of this committee, develop standardization of wireless
LAN. IEEE 802.11 is the first wireless LAN standard established by the IEEE. The medium access
control (MAC) layer protocol that controls communications and the physical layer protocol that
handles data transmission and wireless frequency bands, were mainly established.
・IEEE802.11a
A wireless communication technology used to communicate over a distance of tens of meters;
uses radio waves in the 5 GHz band. The maximum transmission speed is 54 Mbps. It is mainly used
in notebook computers that can use wireless LAN, and it contributes to improving user-friendliness
such as facilitating mobility through wireless network connections. Limitation of usable bands and
prohibition in use outdoors are set in some countries to prevent interference with existing radio
systems. In Japan, the usable bands are 5.15 - 5.25 GHz (W52), 5.25 - 5.35 GHz (W53) and 5.47 -
5.725 GHz (W56), and only W56 can be used outdoors. In W53 and W56, radio transmission stops
and the transmission channel is changed to prevent interference when radio waves from
meteorological radar exist. 5 GHz radio waves, due to their higher frequency than 2.4 GHz, have a
narrower service area and are in comparison susceptible to interference from obstacles.
・IEEE802.11b
A wireless communication technology used to communicate over a distance of tens of meters; uses
radio waves in the 2.4 GHz band. The maximum transmission speed is 11 Mbps. It has a wider
coverage area and is less susceptible to obstacles compared with 5 GHz. However, it is susceptible to
interference and noise from microwave ovens and medical equipment nearby.
・IEEE802.11g
A wireless communication technology used to communicate over a distance of tens of meters;
uses radio waves in the 2.4 GHz band. The maximum transmission speed is 54 Mbps. Mainly
installed in notebook computers that use wireless LAN. It is also used in wireless IP phones and
wireless surveillance cameras. Since it uses the 2.4 GHz band, it has the same disadvantages as
802.11b.
・IEEE802.11n
Next-generation wireless LAN specifications that increase the transmission speed to above
100 Mbps through a technology that uses multiple radio frequencies simultaneously called Multiple
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Appendix
Input Multiple Output (MIMO). It has upward compatibility with 802.11a/b/g.
・Industry Science Medical Band (ISM band)
Frequency bands specified for the industry, science and medical fields; frequencies are assigned in
the 900 MHz band, 2.4 GHz band and 5.7 GHz band.
・Mutual Recognition Agreement (MRA) Law
The abbreviated name of “The Act for Implementation of the Mutual Recognition between Japan
and Foreign States in Relation to Results of Conformity Assessment Procedures of Specified
Equipment (Law No. 111, 2001)”. Wireless LAN equipment approved by a registered foreign
conformity assessment body is treated as equipment conforming to the Technical Regulations
Conformity Certification System of the Radio Law.
・OFDM （Orthogonal Frequency Division Multiplex）
Orthogonal Frequency Division Multiplex system. System in which data is divided and spread
over multiple waves and transmitted in parallel after multiplexing. Since the phases of two waves are
offset by 90 degrees (orthogonal), the waves are not likely to interfere. For this reason, a part of the
multiple waves can be densely arranged, enabling the usage efficiency of frequencies to be
increased.
・PoE （Power over Ethernet）
Standard and method for supplying power to equipment through twisted pair cable for data
transmission. PoE can supply a maximum of 15.4 W of power (maximum 48 V. Maximum current
value is 350 mA).The maximum power on the receiving side is taken as 12.95 w considering the
power loss in the cable.
・ Spectrum Spread (SS) modulation system
A modulation system by spectrum spread technology. Primarily modulated digital signals are
transmitted after being spread to a wide frequency band by secondary modulation with a spread code.
Received signals are demodulated by the same spread code to the original signals.
・TCP/IP (Transmission Control Protocol/Internet Protocol)
A standard communication protocol used in the Internet and intranets.
・WEP (Wired Equivalent Privacy)
A method to encrypt wireless transmission data so as to prevent eavesdropping. It was suggested
that the code could be decrypted since the encryption strength was low; therefore, it is not
recommended as a security measure.
・WPA-PSK (Wi-Fi Protected Access)
A method to encrypt wireless transmission data so as to prevent eavesdropping. By periodically
updating the encryption key, the code becomes difficult to be decrypted; thus, the security is
stronger than that provided by WEP.
・WPA2-PSK
A method to encrypt wireless transmission data so as to prevent eavesdropping. Security is further
enhanced by use of a stronger encryption system than that used in WPA-PSK.
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Appendix
・ Frequency hopping (FH) system
A system of the spectrum spread modulation systems. Rapid changes are made to the transmission
frequency by using spread code.
・ Switching hub
In a normal hub, data selection and pickup is by each terminal but in a switching hub, the
data sent from the terminal is analyzed, destination is detected and data is sent only to that
destination. For this reason, network load is reduced and security is enhanced.
・ Direct spread (DS) system
A system of the spectrum spread modulation systems. The modulated signals are directly
multiplied by spread code to spread the transmitted frequency bandwidth.
・ Equivalent isotropic radiated power
Index that expresses the transmitting performance. Energy radiated in a certain direction from the
antenna is converted to transmitting power of an “equivalent antenna” (ideal antenna) to express the
strength of the wave.
・ Registered Foreign Conformity Assessment Body
Refers to the organization registered as a technical standard assessment organization with which
Japan has concluded the Mutual Recognition Agreement related to approval of standards for
wireless equipment.
Examples of such organizations are the Dutch TELEFICATION B.V, the German CETECOM
ICT Services GmbH, BABTM, Phoenix Testlab GmbH, and EMC Cert Dr. Rasek GmbH, and the
British KTL.
・ Network switch
Also called a switching hub. Refer to “switching hub.”
・ Hot spot
Public locations outside homes and offices, such as railway stations and airports, where Internet
connection services are available. They contribute to improve convenience in accessibility to E-mail
and Web-sites in the field.
・ Wireless IP phone
IP phone or VoIP (Voice over Internet Protocol) phone is a telephone system which uses a
transmission technology to transmit voice signals on an IP network after converting the signals into
packets with compression and digital coding method. When combined with wireless LAN
technology, they are called as Wireless VoIP phones or WVoIP phones.
・ Access point
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Appendix
A relaying device which connects wireless LAN equipment such as wireless LAN enabled
notebook PCs and wireless IP phones to wired LAN, and exchanges data between wireless LAN
equipment and wired LAN. Some access points support router functions. A wireless LAN service
area is established with an access point as a center. An access point is often abbreviated as AP.
With a PoE compatible access point, electrical power can be supplied through a LAN cable, then
power source wiring work to the access point becomes unnecessary.
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Material and Equipment Dept.
4-7 Kioi-cho, Chiyoda-ku, Tokyo-102-8567
Telephone ： 81-3-5226-2020
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NIPPON KAIJI KYOKAI