**United States of America**

**DRAFT PROPOSALS FOR THE WORK OF THE CONFERENCE**

**Agenda Item 1.10.1:** to consider the results of studies, and take
necessary actions, relating to exhaustion of the maritime mobile service
identity numbering resource (Resolution **344 (WRC-97))**;

**Background Information**: This agenda item addresses the potential of
an impending exhaustion of the Maritime Mobile Service Identities (MMSI)
numbering resource. Resolution **344** instructs the Radiocommunication
Bureau to monitor the status of the MMSI resource and report the status
to each WRC.

Maritime mobile service identities (MMSIs) are required for many
shipborne communications equipment (e.g. DSC, mobile earth stations).
The MMSI is a 9‑digit number to uniquely identify ship stations, group
ship stations, coast stations, and group coast stations. Three of the
nine MMSI digits are the Maritime Identification Digits (MIDs) that
represent territory or geographical area of administrations and are
assigned by the ITU. The total possible number of MMSIs is reduced by
ITU Recommendations, which advise administrations to assign MMSIs with
three trailing zeros to ships sailing worldwide and communicating with
foreign coast stations. Additionally, ITU-T Recommendation E.215 has a
requirement to assign MMSIs ending in 3-zeros to vessels requiring
access to certain satellite services. Therefore, for each MID assigned,
there are only 999 numbers available for use by ships with the present
generation of maritime mobile-satellite networks operated by Inmarsat
Ltd. (Standard B, C and M). Additional MIDs are now assigned by the ITU
to administrations when they have used 80% of the MMSIs with three
trailing zeros as documented via the notification requirements of
Article **19**. As the number of vessels carrying such systems
increased, so has the demand for MMSIs with three trailing zeros.

A second issue that can affect the MMSI numbering resource is potential
assignment to aircraft stations. Aircraft used for SAR purposes may have
a need to establish aircraft-to-ship communications using DSC-equipped
radios or using universal shipborne automatic identification systems
(AIS). This AIS communications requirement is addressed in ITU-R M
1371-1, which includes a message to be used for SAR aircraft position
report and requires the use of an MMSI.

**Proposal**:

ARTICLE 19

Identification of stations

**Section II -- Allocation of international series and assignment of
call signs**

**USA/ /1 MOD**

**19.30** 2) As the need arises, ship stations and ship earth stations
to which the provisions of Chapter **IX** apply, and coast
stations[,]{.underline} ~~or~~ coast earth stations [or aeronautical
stations]{.underline} capable of commu­nicating with such ship stations,
shall have assigned to them maritime mobile service identities in
accordance with Section VI of this Article.

**Reasons**: Permits MMSIs to be assigned to aeronautical stations that
require communications to ship stations.

**USA/ /2 ADD**

[**19.31A** 4) Means shall be provided for identifying uniquely mobile
stations operating in automated terrestrial or satellite communication
systems for the purposes of answering distress calls, avoiding
interference and for billing. Identification of the mobile station by
accessing a registration database is satisfactory, provided that the
system can associate the mobile station radio calling number with the
particular mobile station user.]{.underline}

**Reasons**: To provide guidance that identification of mobile stations
can be provided by use of a registration database, thereby allowing use
of all 9-digits of the MMSI.

**USA/ /3 MOD**

**19.35** § 16 The Secretary‑General shall be responsible for allocating
additional maritime identification digits (MIDs) to administrations
within the limits specified, provided that he is satisfied that the
possibilities offered by the MIDs allocated to an administration will
soon be exhausted despite judicious ship station identity assignment as
outlined in Section VI, which should be in conformity with the relevant
ITU‑R and ITU‑T Recommendations.

**Reasons:** The suppression of footnote 2 is consequential to **MOD**
**19.36** shown below.

USA / /4 MOD

**19.36** §17 ~~A single~~ [Each administration has been allocated one
or more]{.underline} maritime identification digit[s]{.underline} (MID)
~~has been allocated initially to each administration~~ [for its
use]{.underline}. A second [or subsequent]{.underline} MID should not be
requested[^1] unless the ~~first~~ [previously allocated]{.underline}
MID ~~allocated~~ is more than 80% exhausted in the basic category of
three trailing zeros and the rate of assignments is such that 90%
exhaustion is foreseen. ~~The same criteria should be applied to
subsequent requests for MIDs.~~

**Reasons**: Clarify the text describing requirements for requesting of
additional MIDs. This is further explained in footnote 2 (**19.36.1**).

Section VI -- Maritime mobile service identities in the maritime mobile
service and\
the maritime mobile‑satellite service

**USA/ / 5 MOD**

**19.99** § 39 When a station^5^ in the maritime mobile
service[,]{.underline} ~~or~~ the maritime mobile‑satellite service[, or
the aeronautical mobile service]{.underline} is required to use maritime
mobile service identities, the responsible admin­istration shall assign
the identity to the station in accordance with the provisions described
in Nos. **19.100** to **19.126**; in so doing, it should take into
account the relevant ITU‑R and ITU‑T Recommendations. In accordance with
No. **20.16,** administrations shall notify the Bureau immediately when
assigning maritime mobile service identities

**Reasons:** Permits MMSIs to be assigned to aeronautical stations that
require communications to ship stations.

**USA/ /6 MOD**

**19.100** § 40 1) Maritime mobile service identities are formed of a
series of nine digits which are transmitted over the radio path in order
to uniquely identify ship stations, ship earth stations, coast stations,
coast earth stations[, aeronautical stations,]{.underline} and group
calls.

USA/ /7 MOD

**19.101** 2) These identities are formed in such a way that the
identity or part thereof can be used by telephone and telex subscribers
connected to the [public]{.underline}~~general~~ telecommunications
network principally to call ships automatically in the shore-to-ship
direction. [Access to public networks may also be achieved by means of
free form numbering plans, so long as the ship can be uniquely
identified using the systems registration database (see No. **19.31A**)
to obtain the ship station identity, call sign or ship name and
nationality.]{.underline}

**Reasons**: Allows use of free form numbering plans thereby alleviating
the requirement for use of three trailing zeros.

108. B -- Maritime identification digits (MIDs)

**USA/ /8 ADD**

**[19.108A]{.underline} § [42]{.underline}** [The maritime
identification digits M~1~I~2~D~3~]{.underline} [are an integral part of
the maritime mobile service identity and denotes the geographical area
whose administration is responsible for the station so identified (see
Nos.]{.underline} **[19.102]{.underline}** [to]{.underline}
[**19.106**).]{.underline}

**Reasons**: Provides additional definition for MIDs denoting linkage to
geographical area.

USA/ /9 SUP

~~**19.109** § 42~~

**Reasons**: This change is consequential to **MOD 19.31A** above.

**19.110 C -- Ship station identities**

**USA/ /10 MOD**

**19.112** *a)* follow the guidelines contained in the ~~relevant~~
[most recent version of Recommendation]{.underline} ITU-R ~~and ITU-T
Recommendations for~~[M.585 concerning]{.underline} the assignment [and
use]{.underline} of ship station identities.

**Reasons**: Gives ITU-R responsibility for management of MMSI and MID
resources.

**USA/ /11 MOD**

**19.114** *c)* take particular care in assigning ship station
identities with six significant digits (three-trailing-zero identities),
which should be assigned only to ship stations which can reasonably be
expected to require such an identity for automatic access on a
world-wide basis for public switched networks~~;~~[, in particular for
mobile satellite systems accepted for use in GMDSS on or before 1
February 2002, as long as those systems maintain the MMSI as part of
their numbering scheme.]{.underline}

**Reasons**: Clarification that MMSI with three trailing zeros is
applicable primarily for earlier mobile satellite systems.

**USA/ /12 SUP**

**19.115** *d)*

**Reasons**: Originally, it was thought that a significant number of
vessels which sailed domestically or on a regional basis and also
required automatic access to Public Switched networks via DSC would be
able to use a regional or domestic designator (8 or 9 respectively) as
the first digit of the MMSI resulting in only two trailing zeros being
available. There are no current or planned DSC coast stations planning
to provide the automatic access, therefore, reserving MMSIs with one or
two trailing zeros for this purpose is no longer necessary, confusing
and undesirable.

**USA/ / 13 SUP**

**19.116** *e)*

**Reasons**: Since there are no longer needs for numbers ending with one
or two zeros to be reserved for automatic access to PSTN via DSC, there
are only two types of formats, those with three trailing zeros used
mainly for INMARSAT and all others therefore there is no need for the
above provision.

**USA / / 14 MOD**

RESOLUTION 344 ([Rev.]{.underline}WRC-~~97~~[03]{.underline})

~~Exhaustion~~[Management]{.underline} of the maritime mobile service
identity\
numbering resource

The World Radiocommunication Conference (~~Geneva, 1997~~ [Geneva,
2003]{.underline}),

noting

a\) that the installation of digital selective calling equipment or
Inmarsat B, C or M ship earth station equipment on ships participating
in the Global Maritime Distress and Safety System (GMDSS) on a mandatory
or voluntary basis requires the assignment of a unique nine-digit
maritime mobile service identity (MMSI);

b\) that such equipment offers the possibility to connect with public
telecommunications networks;

c\) that only mobile-satellite systems have been able to resolve the
various billing, routing, charging and signalling requirements needed to
provide full two-way automatic connectivity between ships and the
international public correspondence service;

d\) that ships using the present generation of mobile-satellite ship
earth stations have to be assigned an MMSI ending with three trailing
zeroes in order to support automatic access to public telecommunication
networks through a diallable ship telephone number [whose format
is]{.underline} compliant with ITU‑T Recommendation E.164[,]{.underline}
but can only accommodate the first six digits of the MMSI;

e\) that the first three digits of a ship station MMSI form the maritime
identification digits (MID), which denote the ship\'s administration or
geographical area of origin;

f\) that each MID only has sufficient capacity to identify 999 ships
using the three trailing zero number format, with the result that the
widespread use of MMSIs with three trailing zeroes rapidly exhausts the
capacity of each MID,

considering

a\) that digital selective calling distress alerts require valid
identities recognizable by search and rescue authorities in order to
ensure a timely response;

b\) that Recommendation ITU-R M.585 contains guidance for the assignment
of MMSIs,

recognizing

a\) that even domestic ships which install the present generation of
ship earth stations operating to Inmarsat B, C or M standards will
require the assignment of MMSI numbers from those numbers [originally
intended]{.underline} ~~reserved~~ for ships communicating worldwide,
further depleting the resource;

b\) that future growth of Inmarsat B, C or M ship earth station use by
non‑compulsory ships may further deplete the MMSI and MID resources;

c\) that future generations of mobile-satellite systems offering access
to public telecommunication networks and participating in the Global
Maritime Distress and Safety System will employ a free-form numbering
system that need not include any part of the MMSI,

noting further

a\) that ITU-T has recommended that ITU-R assumes sole responsibility
for managing the MMSI and MID numbering resources;

b\) that ITU-R can monitor the status of the MMSI resource, through
regular reviews of the spare capacity available within the MIDs already
in use, and the availability of spare maritime identification digits ,
taking account of regional variations,

instructs the Director of the Radiocommunication Bureau

1 to manage the allotment and distribution of the MID resource within
the MMSI numbering format, taking into account:

-- Sections II, V and VI of Article **19**;

-- regional variations in MMSI use;

-- spare capacity within the MID resource; and

-- the guidelines on MID and MMSI management contained in the most
recent version of Recommendation ITU-R M.585, in particular as regards
the re-use of MMSIs;

2 to report to each world radiocommunication conference on the use and
status of the MMSI resource, noting in particular the anticipated
reserve capacity and any indications of rapid exhaustion of the
resource,

resolves to invite ITU-R

to keep under review the Recommendations for assigning MMSIs, with a
view to:

-- improving the management of the MID and MMSI resources; and

-- identifying alternative resources if there is an indication of rapid
exhaust of these resources,

instructs the Secretary-General

to communicate this Resolution to the International Maritime
Organization.

**Reasons**: Changes needed to Resolution **344 (WRC-97)** in order to
implement the new resource management responsibilities.

[^1]: ^2^ **[19.36.1]{.underline}** In no circumstances may an
    administration claim more MIDs than the total number of its ship
    stations notified to the ITU divided by 1 000, plus one.
    Administrations shall make every attempt to reuse the MMSIs assigned
    from earlier MID resources, which become redundant after ships leave
    their national ship registry. Such numbers should be considered for
    re‑assignment after being absent from at least two successive
    editions of LIST VIIA of the ITU service documents. Administrations
    seeking additional MID resources must meet the criteria of having
    notified all previous assignments, in accordance with No. **20.16**.
    This criteria applies only to MMSIs in the basic category and to all
    MIDs assigned to the administration.