2.2

Private IP address

2.2.1

Use of private IP addresses

NACCS user network assigns private IP addresses for the following purposes:(If the connection form between the NACCS center server and each user system is the Internet(netNACCS connection, WebNACCS connection, or gateway connection (ebMS processingmode), a NACCS center IP address is not granted.)[1] To employ a logically closed network for the NACCS user network.
[2] To prevent unauthorized access by non-NACCS users.
[3] To be unbound by global IP address exhaustion.
The TCP/IP network layer protocol at NACCS is IPv4 (Internet Protocol version 4).
No support is provided for IPv6 (Internet Protocol version 6). The user's existing LAN needs to be
IPv4-based to connect to the NACCS Center server. Connection to the NACCS user network via a
IPv6-based LAN is not allowed. Nevertheless, connection is allowed if a gateway computer is set
up at the border between IPv6-based LAN and NACCS user's network to translate IPv6 to IPv4.

! An IP address is a numerical address used to identify each computer connected to the
network, and is required when building a computer network using TCP/IP.

! A private IP address is an IP address assigned in accordance with unique structure Thisis used for such networks as a network closed within the company.

! A global IP address is a globally unique assigned and managed IP address.
IANA (JPNIC in Japan), an IP address management body, assigns numbers to users to
avoid address overlaps.
Recently, the number of assigned addresses has almost reached the upper limit ofnumbers which can be assigned, so running out of addresses has become an issue.

2-2-1

2.2.2

Private IP address architecture

The IP address is expressed by 4 fields separated by "." (periods).
VVV .
(Field A)

XXX .
(Field B)

YYY .
(Field C)ZZZ(Field D)

The IP address architecture used by NACCS is shown in Table 2.2.1:

Table 2.2.1
Field A

IP address architecture

Field B

Field C

Field D1 - 254

1 - 254

designated bydesignated bydesignated by

NACCS Center

NACCS Center

NACCS Center

20 - 98

Range ofassignment

10

user
100 - 177

180 - 189
Assignment
method

Fixed

2-2-2

2.2.3

Relationship between IP address and subnet mask

The following value is applied as the subnet mask required for IP address setting (common to allusers).
255. 255. 255. 0
An IP address is composed of a network address that represents the network the computers andother devices belong to, and a host address that represents those computers and other devices
within the network.
The subnet mask works as a marker to separate the network address and host address parts
within the IP address.
For example, when the following is set,

IP address：
subnet mask:

10. 169. 254.
255. 255. 255.

30

Network address part Host address partthe IP address "10. 169. 254" represents the network address part, while "3" represents the hostaddress part.
The same network address will applied to computers connected to the same LAN.
Each device connected to the same LAN is distinguished by the host address part.

Network address part: 100.100.100

Network address part: 10.169.254
10.169.254.2

100.100.100.2
10.169.254.1

100.100.100.1

ComputerComputer

Hub*

RouterHub** "Hub" refers to a "switching hub".
10.169.254.3

100.100.100.3

ComputerIP address： 10.169.254.xxx
Subnet mask ：255.255.255. 0

ComputerIP address：100.100.100.xxx
Subnet mask ：255.255.255. 0

Figure 2.2.1 Subnet Mask and the Network

2-2-3

2.2.4

IP address assignment by NACCS Center

Since NACCS is a system for administrative procedures, users' computers that connect to the
NACCS Center server to process export/import and port related procedures must be identified.
NACCS Center, for this purpose, will manage IP addresses of NACCS user computers andprovide a unique address for each user computer.
The user computer to which an IP address will be assigned by NACCS Center must be locatedin Japan.
The same applies to users who already have their own private IP addresses: They, too, must
use the IP address uniquely determined and managed by NACCS Center to receive NACCS
services.
If, however, the IP address of a user's in-house system overlaps with the one assigned by
NACCS Center, the Center shall make adjustment by assigning a separate private IP address
which does not overlap with that of the user's system, provided that there is no adverse effecton system operation.
Note that it is allowable that a private IP address assigned by NACCS Center is converted toanother IP address at user's network and is assigned to user's computer with the precondition
that the IP address uniquely corresponds to the IP address assigned by the NACCS Center.
When converting an IP address for use, correspondence between the IP address assigned by
NACCS Center and the IP address after conversion should be immediately presented when
NACCS Center requests.
For example, when converting an IP address on the communication equipme nt installed by theuser using the NAT function, the setting is configured so that static conversion (conversion
where converted IP address is always converted to the same IP address if original IP address isthe same) is carried out, and setting details can be presented to the NACCS Center.

! Although it is possible to use cloud services as a user-side Gateway computer, when it isnecessary to use systems based on EDI specifications and business specifications, suchas installing user-side Gateway computers (region, etc.) and NACCS connection routers towhich the NACCS center assigns IP addresses in Japan, it is the same as the case of
on-premise systems.

2.2.5

Where to assign the IP address

An IP address is assigned according to the type of user connection:(1) Peer-to-peer connection
router, user-side computer(2) Router connection
router, user-side computer(3) Gateway connection*router, user-side gateway computer* Gateway connection refers to SMTP two-way connection and to SMTP/POP3 connection.

2-2-4

2.2.6

IP address allocation rules(1) IP address for NACCS user computer
NACCS Center will assign IP addresses, with all the values in the fields from A to D being
specified, to user-side computers and gateway computers that connect to the NACCS
Center server.
(2) IP address for computer of intraoffice use located within the same LAN as the NACCS
user computer
NACCS Center will specify fields A to C for computers connected to the same LAN as the
NACCS user computer but only for intra communications (not used for NACCS service).
As for field D, the user will assign any value that does not overlap with the IP address of
any NACCS user computers.
(3) Limitation on IP address assignment to user computers
In field D, NACCS Center will assign the value "1" for the router. Users may not assign "1" infield D to their computers.

(1)<NACCS user computer>
IP address: AAA.BBB.CCC.DDD

NACCS connection
routerdesignated by NACCS Center(2)<Intraoffice computer>
IP address: AAA.BBB.CCC.EEEHub

IP address: AAA.BBB.CCC.1

designated by NACCS Center

designated by NACCS
CenterAssigned by the user
arbitrarily(3)

NACCS user LAN
Figure 2.2.2

NACCS user network

IP Address Assignment (router connection)

2-2-5

2.2.7User LAN setup (typical cases)

Table 2.2.2 shows the typical cases in setting up a user LAN to be connected to NACCS when
an intraoffice network is already provided with a user's unique IP address.

Table 2.2.2

Variations of User LAN Configuration

NOT connecting to
intraoffice network from
NACCS user LAN

Connect to intraoffice
network from NACCS
user LAN

Case 3
Separate NACCS
user LAN andintraoffice network by
setting up user router

Build new
NACCS userLAN

Utilize existing
intraoffice
network

Case 4

Case 5

Use 2 LAN cards(NIC) forcomputersconnecting to
NACCS

Create 2 logicalsubnets on 1 LAN by
setting up userrouter corresponding
to secondary IP

Case 1
Physically separate
NACCS user LAN andintraoffice network

2-2-6

Case 2
Switch all IP
addresses on
NACCS user LAN to
NACCS-designatedaddresses

CASE 1
User's current LAN setup
Simple LAN setup using a hub
existing computer A
IP address: 100.100.100.1

existing computer B
IP address: 100.100.100.2

existing computer C
IP address: 100.100.100.3

hub
hub

Designate existing computer A as the
NACCS user computer, and B and C for
intraoffice communications only.

Figure 2.2.3 Case 1: Current LAN Configuration
New user LAN configuration[1] Set up a NACCS connection router designated by NACCS Center. The Center assigns an
IP address for setting up the router.
[2] The user changes the IP address of existing computer A to a private IP address
designated by NACCS Center.
[3] As for existing computers B and C, the user changes the IP address in Fields A to C toprivate the IP address designated by NACCS Center and sets an arbitrary value i n Field
D.

NACCS user LAN

Changed to NACCS
designated address

Changed to NACCS
designated address

IP address: 10.169.254.2

IP address: 10.169.254. 3

Set arbitrary by the user

IP address: 10.169.254. 4

existing computer B(for intraoffice use)

existing computer A(NACCS user
computer)existing computer C(for intraoffice use)

NACCS user network

NACCS connection router
IP address: 10.169.254.1

Hub

Designated and setup by NACCS Center

Figure 2.2.4 Case 1: New LAN Configuration
2-2-7

CASE 2User's current LAN setup
Communication within network outside NACCS user LAN (LAN, WAN) using router
existing computer A
IP address: 100.100.100.2

User's own network(LAN, WAN)

existing computer B
IP address: 100.100.100.3

IP address:
100.100.100.1

Hub

User's router

Existing computer A is for intraofficecommunications only. Use existing computer B as
NACCS user computer.

Figure 2.2.5 Case 2: Current LAN Configuration
New user LAN configuration[1] Set up a NACCS connection router designated by NACCS Center. The Center assigns an
IP address for setting up the router.
[2] The user changes the IP address of the LAN connected to the NACCS user computer(existing computer B) to the NACCS IP address architecture.
[3] The user changes the IP address of the NACCS user computer (existing computer B) to
the private IP address designated by NACCS Center.
[4] As for existing computer A and the user's router, the user changes the IP address in
Fields A to C to a private IP address designated by NACCS Center and sets an arbitraryvalue in Field D.
NACCS user LAN
Arbitrarily designated by the user

IP address: 10.169.254. 4
existing computer A(for intraoffice use)

Changed to NACCS
designated address* This will not apply when user's own network isusing the same architecture as the IP address
newly assigned by NACCS Center, in which casea separate report to NACCS is required.

IP address: 10.169.254.2
existing computer B(NACCS user computer)

Arbitrarily designatedby the user

* User's own network(LAN, WAN)

IP address:
10.169.254. 3

HubUser's router
NACCS user network

Change to NACCS
designated address
NACCS connection router
IP address: 10.169.254.1
Designated and setup by NACCS Center

Figure 2.2.6 Case 2: New LAN Configuration
2-2-8

CASE 3User's current LAN setup
Communication within network outside NACCS user LAN (LAN, WAN) using router
existing computer A
IP address: 100.100.100.2

User's own network(LAN, WAN)

existing computer B
IP address: 100.100.100.3

IP address:
100.100.100.1
Hub

User's routerSet up new LAN for NACCS without changing
existing LAN settings.

Figure 2.2.7 Case 3: Current LAN Configuration
New user LAN configuration[1] Set up a NACCS connection router designated by NACCS Center. The Center assigns an
IP address for setting up the router.
[2] The user arranges a NACCS user computer, new hub, and new user router to connect to
the NACCS user LAN and sets a private IP address designated by NACCS Center for the
new user router and NACCS user computer.
[3] Connect NACCS user LAN and existing LAN with new user router. This requires nochange in the IP address architecture of the user's existing LAN.
existing computer B
IP address: 100.100.100.3

existing computer A
IP address: 100.100.100.2* User's own network(LAN, WAN)

IP address:
100.100.100.1* This will not apply when user's own
network is using the same architecture as
the IP address newly assigned by NACCS
Center, in which case a separate report to
NACCS is required.

Hub

User's router

IP address: 100.100.100.4

Set arbitrary by the user
according to intraoffice IP
address structure

User's newrouterSetup as designated by
NACCS Center

IP address:
10.169.254. 3

NACCS user LAN
Set arbitrary by the user

IP address: 10.169.254.2
NACCS user computer

New hub

NACCS connection router
IP address: 10.169.254.1
Designated and setup by NACCS Center

Figure 2.2.8 Case 3: New LAN Configuration
2-2-9

NACCS user network

CASE 4User's current LAN setup
Communication within network outside NACCS user LAN (LAN, WAN) using router
existing computer A
IP address: 100.100.100.2

User's own network(LAN, WAN)

existing computer B
IP address: 100.100.100.3

IP address:
100.100.100.1

Hub

User's routerSet up new LAN for NACCS without changing
existing LAN settings.

Figure 2.2.9 Case 4: Current LAN Configuration
New user LAN configuration[1] Set up a NACCS connection router designated by NACCS Center. The Center assigns
an IP address for setting up the router.
[2] Set up a new hub to build a NACCS user LAN, and insert the LAN card (NIC) for using
NACCS into the existing computer. The user sets up a private IP address designated by
NACCS Center for the newly inserted LAN card.
[3] Connect the newly inserted LAN card and NACCS connection router via the new hub.
It is not necessary to change the IP address structure of the user's existing LAN.

existing computer A(for NACCS andintraoffice use)

User's router

NACCS user LAN

IP address:
100.100.100.1
IP address:
100.100.100.2

IP address:
10.169.254.2

New hub
Setup as designated by
NACCS Center
Hub

IP address:
100.100.100.3* User's own network(LAN, WAN)

IP address:
10.169.254.3

NACCS user network

existing computer B(for NACCS and intraoffice use)
* This will not apply when user's own
network is using the same architecture as
the IP address newly assigned by NACCS
Center, in which case a separate report to
NACCS is required.

NACCS connection router
IP address: 10.169.254.1
Designated and setup by NACCS Center

Figure 2.2.10 Case 4: New LAN Configuration
2-2-10CASE 5User's current LAN setup
Communication with network outside NACCS user LAN (LAN, WAN) using user router
supporting secondary IP function
existing computer A
IP address:
100.100.100.2

existing computer B
IP address:
100.100.100.3

User's own network(LAN, WAN)

existing computer C
IP address:
100.100.100.4

IP address:
100.100.100.1
Hub

User's router supporting
secondary IP function

Use existing computer A as NACCS user computer,and use all existing computer A, B and C also for
intraoffice use.

Figure 2.2.11 Case 5: Current LAN Configuration
New user LAN configuration[1] Set up a NACCS connection router designated by NACCS Center. The Center assigns an
IP address for setting up the router.
[2] Set up a network address designated by NACCS Center as the secondary address for theuser router supporting the secondary IP functionality (capable of setting up multiple
logical subnets on a single physical port).
[3] Use the user router as a default gateway and set routing information for NACCS to static.
[4] Set a private IP address designated by NACCS for the user computer.

existing computer A(for Air-NACCS and intraoffice use)
IP address: 10.169.254.10NACCS* User's own network(LAN, WAN)

existing computer B(for intraoffice use)
IP address: 100.100.100.3

existing computer C(for intraoffice use)
IP address: 100.100.100.4

Set default ga teway as
user's ro ute r

User's router* This will not apply when user's own
network is using the same architecture as
the IP address newly assigned by NACCS
Center, in which case a separate report to
NACCS is required.

Set packe t for NACCS
Center ser ver alo ne asstatic2 logical subnets(100.100.100.0, 10.169.254.0)
both processable

Hub

NACCS user network

NACCS connection router
IP address: 10.169.254.1
Designated and setup by NACCS Center

Figure 2.2.12 Case 5: new user LAN Configuration
2-2-11

Supplements
Precautions:
The NACCS connection router does not exchange routing information with other routers.
Users connecting the NACCS user LAN and their intraoffice network must set to static
routing information for the user's router which is a gateway for their intraoffice network andset the user router to a default gateway setting for computers within the NACCS user LAN.

NACCS user LAN
NACCS
connection router

Host

NACCS user network

Hub

Gateway
computer[1][2]

Computer[3]
ComputerUser'srouterUser's own network(LAN, WAN)

(default gateway)

Figure 2.2.13 Setting Routing Information for User’s Router[1] A message (data) sent by the user is first transmitted from the NACCS user LAN to theuser router set to the default gateway.
[2] When a message (data) addressed to NACCS is sent by the user, it will be directed to the
NACCS connection router in the user router based on the routing information set to staticand then transmitted from the NACCS connection router to the NACCS user network.
[3] When a message (data) addressed to the user's intraoffice network is sent by the user, it
will be transmitted from the user router to the user's intraoffice network.

2-2-12

2.2.8IP address translation(1) IP address translation
Since NACCS is a system for administrative procedures, users' computers that connect to
the NACCS Center server to process export/import and port related procedures must be
identified. NACCS Center, for this purpose, will manage IP addresses of NACCS user
computers and provide a unique address for each user computer. Note that it is allowablethat an IP address assigned by NACCS Center is converted to another IP address at theuser's network and is assigned to the user's computer with an assumption that that IP
address will uniquely correspond to the IP address assigned by NACCS Center.
(2) IP address conversion on gateway computer
In the case of gateway connection, IP address conversion on the gateway computer ispermitted:
However, due to security reasons, the user must keep a log of messages transmitted toand received by the gateway computer and save the log for a period of one year.

2-2-13

<In Peer to Peer Connection>User-side computer

User-side communication
NACCS
equipment
connection router☆

AP
IP address
conversion☆⇔△* With the precondition of one-toone static conversion<In Router Connection>☆
User-side
computerUser-side
computer

NACCS
User-side communication
connection routerequipment☆

AP
IP address
conversion

User-side
computer☆

☆⇔△* With the precondition of one-to-one
static conversion<In Gateway Connection>

IP address
conversion○☆

User-side communication
NACCS
equipment
connection routerAP
IP address
conversion
User-side
Gateway
computer☆⇔△* With the precondition of
one-to-one staticconversion△ : Private IP address assigned by
NACCS Center☆ : Private IP address assigned by
users

AP
User system: Access point

NACCS user network

Record and save the archive(log) transmitted message
contents for 1 year.

Figure 2.2.14 Prohibition of IP Address Translation

2-2-14NACCS Center
server2.2.9Boundaries of liability for failures

NACCS Center shall assume liability for failures between the NACCS Center server and the
NACCS connection router on the user side.

Peer-to-peer
connection

NACCS
connection
routerAP

User's network
backbone

NACCS
connection
routerRouterconnection

Gateway connection

User system

NACCS
connection
routerAP: Access point

User's liability

NACCS Center
server

NACCS's liability

Boundaries of liability for failures

Figure 2.2.15

Liability Coverage for Possible Failures

2-2-15

2.2.10NACCS Information and IP address(1) NACCS Information
NACCS Center sets up a website, titled as "NACCS Information" exclusively for NACCS
users, aimed at providing latest news and announcements concerning NACCS, status of
the NACCS Center server, code updates and latest version of packaged software available.
NACCS Information consists of sites for visitors and NACCS users, whose access level
and authentication method vary. Information only available to NACCS users, such as thelatest version of software packages, is posted only on the NACCS User Website.
Table 2.2.3
Types

Types of NACCS Information and User Authentication Methods
Users
Authentication Method
All visitors including
No authentication necessary.
Visitor's Website
non-NACCS users
Accessible by all visitors.
Closed network users
Authentication by private IP
address assigned by NACCS
Center
NACCS User
WebsitenetNACCS users
Authentication by digital user
WebNACCS users
certificates for netNACCS users
and WebNACCS users(2) Setting dedicated IP address in the case of gateway connection
Users choosing gateway connection need to build a system to access NACCS informationfrom a gateway computer or a computer connected to the gateway computer.
NACCS Center, upon request from a gateway connection user, issues an IP address solely
to access NACCS information, in addition to the one assigned for the use of NACCS.
Users in the gateway connection, when accessing NACCS Information, must comply withthe security standards formulated by the NACCS Center, including the implementation ofanti-virus scanning on the gateway computer as well as other computers connected to thegateway computer.

2-2-16