Upgrading to HSD

Requirements for MESs 

All operational Mobile Earth Stations (MESs) must satisfy four basic requirements as follows:- 

Financial

The customer must be able to pay the bills and must select either an Inmarsat Service Provider (ISP) or Accounting Authority (AA) that will liaise with LESs for billing purposes.  Maritime customers who will use the MES for distress and safety purposes must be registered with an Accounting Authority. 

Legal

The MES must meet all national licensing requirements  The Routing Organisation is responsible for the enforcement of the national licensing requirements. 

Contractual

The MES operator or owner must agree to the Inmarsat Terms and Conditions for the Utilisation of the Space Segment, and realise that any violation of these terms and conditions could result in the suspension of or permanent withdrawal of access to the space segment. 

Technical upgrade

The nature of technical upgrade needed to activate an Inmarsat B's HSD function depends upon the MES model type. To learn more about HSD upgrades contact a local distributor:

Service Activation Process 

Service Activation can be initiated by the owner of an MES or anyone who is acting on behalf of the owner.  However, an applicant who is not the owner (for example, an agent) must pass the Service Activation Registration Form to the owner for signature.

The applicant selects the Inmarsat Service Provider or Accounting Authority who will be responsible for processing the traffic charges associated with the terminal.  The details of the owner, MES and billing arrangements are recorder on the Service Activation Registration Form which is then signed by the owner of the MES and forwarded to the relevant national Routing Organisation (RO) or Inmarsat Service Provider (ISP) for approval and allocation of Inmarsat Mobile Number.

After processing and approving the application the RO or ISP passes the information on to the Inmarsat Service Activation Unit in London, England who ensure that the details of the MES are transmitted to all Land Earth Stations so that access may be granted.

The Inmarsat-B Service Activation process is automated and normally takes about 24 hours providing there are no queries related to the application.

Inmarsat-B HSD MES Numbering

The Inmarsat Mobile Number (IMN) is the subscribers’ number, which is used for calling a Mobile Earth Station (MES).  It performs exactly the same function as a PSTN or PSDN number.  The exact form of the IMN varies from one Inmarsat service to another and so can be used to verify the type of service associated with the number.

The Inmarsat Mobile Number (IMN) for an Inmarsat-B HSD user takes the following form

  * Currently only the Duplex HSD service is available. 

Inmarsat-B IMNs are assigned by Inmarsat and are distributed in batches to Routing Organisations and Inmarsat Service Providers for allocation to their customers.

Installation and testing 

No customer will thank you for running up his satellite communications bill for carrying out testing, configuration and trouble-shooting that could have been done on an ISDN line back at the office.  It is good practice to check any Inmarsat-B HSD application first on an ISDN line.  This can be done on a single Basic Rate line as only one 64Kbps (B) channel is used for the application.  Calls can therefore be made from one B channel to the other.

An ISDN to ISDN test will verify that the application works in the office environment.  The next test should include the satellite delay.  Many off the shelf applications will not have been tested with a round-trip delay on the order that can be expected with the Inmarsat-B Service (i.e. 500-1400ms).

Each end of the application can be connected to the ISDN BRI either directly, if the equipment is fitted with a BRI, or through the ISDN Terminal Adapter (TA) if only the serial interface is available using interface converters as necessary (see Section 2.4.1, Basic Test Tools, below).  If required both ends of the application can be connected to the dual channel TA and calls made from one DTE to the other.  If the DTE equipment does not have dialling features calls can be initiated from the TA either via the front panel or from a PC connected to the control port on the TA.

A typical pre-installation check-list may comprise the following checks:

User familiarisation

The main objective of an Inmarsat HSD system provider should be to provide an HSD application that is as simple to use as its ISDN equivalent

In practice this is determined by the extent to which the Inmarsat-B Premium HSD MES has automated dialling features and the extent to which the HSD application can use these features. To learn more about HSD dialling features on different MES models click below.

1.Inmarsat-B HSD dialling features:

2. HSD applications dialling features:

The actual operation of the equipment should be done whenever possible using an ISDN line in the first instance so that the user can become familiar with the operation of the equipment without running up an unnecessary satellite traffic bill.

Post-sales support 

Once installed it would be reasonable to expect the equipment to function reliably for its working life.  Modern IT equipment has a high degree of reliability and equipment failures are decreasingly likely to be the cause of application failures.  More likely causes of application failure are likely to be: 

In the ideal world, the HSD system provider would have a duplicate system in the office so that test calls can be made in the event of problems to determine if the problem lies at the remote location or in the office.  See also Section 2.4, Trouble-shooting tools and techniques. 

It is often the case that users become at least as familiar and often more familiar with the day-to-day performance of the HSD application than the equipment supplier.  On this basis it makes good sense to review the performance and use of the equipment from time to time with the customer so that strengths and weaknesses can be identified and possible improvements made for future systems.