Re: [Ccglrit-gcclrit] June 12-14 meeting of the Ad hoc Working Group onEngineering Aspects of LRIT, Hamburg Germany

Friday, 1 June 2007

Jeff,

Thanks for the e-mail.

There is alot of information in the e-mail and it will certainly provide
for useful discussion at the Hamburg meeting. Given that the intent of
the LRIT communications document is to add technical details to the
basic functions outlined in the Performance Standards, it seems a good
idea to add some boundaries to the communication link between the CSP
entity and the ASP entity. Ignoring this communication link in the
communications document or simply implementing a "anything goes"
strategy seems dangerous.

If the CSP entity takes the "raw" payload from the shipborne equipment
and does not format any of the information before it is sent to the ASP
than that seems ok (We can modify document text to handle this).
However, I think the delivery mechanism(s) that the CSP uses to send the
information to the ASP should be specified. We should at least list
acceptable mechanisms and ensure some standard level of data security.

If I understand correctly (maybe I don't), many CSPs deliver data
information (such as shipborne location co-ordinates) to the associated
ASP over the internet. Thus, application software at the CSP would have
to build IP packets with the "raw data" from the shipborne equipment as
the payload. If the CSP entity can build IP packets than why can't it
build SOAP messages with the "raw data" as the payload?

Jeff: I would be interested in chatting with you via phone early next
week if you are available and willing?

Thanks,

Craig Hayley
System Engineer
Candian Coast Guard

________________________________

From: ccglrit-gcclrit-bounces(a)lists.ncf.ca
[mailto:ccglrit-gcclrit-bounces@lists.ncf.ca] On Behalf Of Jeff Douglas
Sent: Friday, June 01, 2007 2:02 PM
To: ccglrit-gcclrit(a)lists.ncf.ca
Cc: 'Jeff Chandler'; 'Iain Hayes'
Subject: Re: [Ccglrit-gcclrit] June 12-14 meeting of the Ad hoc Working
Group onEngineering Aspects of LRIT, Hamburg Germany

Craig

I'm sorry that I missed the June meetings there - so please excuse any
duplication or overlap below as the topics may have been discussed
during the working groups.  Some thoughts on the question of how data
formats arise, and the appropriate point within the LRIT Infrastructure
follows:

As a practical matter many ASPs today support most, if not all, of the
satellite providers likely to meet the performance standards for LRIT
(and thus be potentially CSPs or support CSPs).  Therefore I would
disagree that this aspect is overly burdensome.  Converting data is not,
in context, likely to determine the success or failure of an ASP
considering all other factors within an ASP's list of responsibilities
(securing customers, maintaining a data center, certification into
LRIT).  

However; in our view that discussion itself is rendered moot by the
bigger question of what is technically feasible for a CSP.

The view here is that CSPs will be unable to convert data to the
proposed format (or any other standard format for that matter).

Each CSP provides a communications path via a specific satellite
network.  However CSPs do not, in most instances, have knowledge of
payload interpretation, protocol or format of the data exchanged between
the ASP and the Shipboard Equipment.  Such aspects are handled by
firmware, scripting or other configuration mechanisms that are specific
to each equipment vendor.  Hence the data transmitted via any given CSP
may vary from device-to-device and change over time as new software or
firmware revisions are made to the onboard equipment.

To our knowledge, all potential CSPs provide flexibility in the
representation of the LRIT requirements over their networks (e.g. the
raw encoding of a position report).  Most potential CSPs also provide
several different delivery mechanisms which are proven both technically
and commercially.  As the CSP cannot generally control the
scripting/firmware/configuration options present on each piece of
Shipboard Equipment it becomes technically infeasible to assign any data
translation capabilities to the CSP.

Furthermore; even if a CSP did have knowledge of the payload protocol -
and thus could translate it - that approach may have unintended
consequences.  If would lead to a lowest-common-denominator approach
within the data available to ASPs.  Shipboard Equipment and CSPs often
make data available in addition to the fields required for LRIT.  We
anticipate that ASPs are likely to use this additional data to offer
services complementary to LRIT - in terms of their offerings to fleet
owners and operators.  Consequently; we do not believe that it is
desirable for a CSP to remove all additional data as that would limit
the overall utility of the LRIT system to fleet owners and operators.
Such a step would also reduce the commercial opportunities available to
ASPs.

Our view is that the earliest point in the LRIT infrastructure where
sufficient information is available to standardize a format is at the
ASP.

Of note the ability to satisfy the Performance Standards arises through
the use of two system components in conjunction:

a) Shipboard equipment; including configuration options (scripts,
firmware versions etc)

b) The CSP; including the account configuration and selected delivery
formats etc (i.e. VPN, Internet, header formats)

There are two additional notes here - to avoid potential
misinterpretation of the above: 

1)       A CSP may also act as an ASP.  In that case the ASP+CSP can
take responsibility for the configuration of shipboard equipment - and
thus is able interpret the payload data fully within the ASP aspects of
its dual role.

2)       It may initially appear that Inmarsat-C equipment operating in
according to the baseline PDR specifications is an exception - as this
is a rare case of a network operating defining a position reporting
protocol.  However; it should be noted that most deployed Inmarsat-C
equipment extends the Inmarsat-C baseline standards in vendor
proprietary ways - and this is specifically allowed within the
Inmarsat-C baseline PDR specifications.

3)       Finally; any translation to a common format could not be
performed once per "physical" satellite network.  The "CSP" for
example
in Inmarsat could be a Land Earth Station operator, other distribution
partner or Virtual Network Operator (i.e. Inmarsat-D+).  The same
comment applies to other satellite providers who elect to have
distribution partner(s) act as the CSP.  It should be noted that this
may be required by the telecommunications regulators in some countries
(where a specific legal entity or reseller holds the concession to land
traffic from a given network within a defined country).  Consequently,
care should be taken here not to equate "CSP" in the LRIT lexicon with
"Satellite Network" in the sense of the physical satellite
constellations available - there may be many CSPs sharing the same
physical satellite network.  Hence the apparent simplicity of the
"one-CSP" vs. "many-ASP" argument falls down.  It is actually quite
possible that there would be fewer ASPs than CSPs in practice once LRIT
is deployed.

Best Regards

Jeff Douglas

Director

ABSOLUTE SOFTWARE INC

www.absolutesw.com <http://www.absolutesw.com/>  

________________________________

From: ccglrit-gcclrit-bounces(a)lists.ncf.ca
[mailto:ccglrit-gcclrit-bounces@lists.ncf.ca] On Behalf Of Hayley, Craig
Sent: Friday, June 01, 2007 09:43
To: ccglrit-gcclrit(a)lists.ncf.ca
Subject: Re: [Ccglrit-gcclrit] June 12-14 meeting of the Ad hoc Working
Group onEngineering Aspects of LRIT, Hamburg Germany

You make a fair point... I would suggest other interested parties (such
as ASPs wishing to bid on the ASP function for the IDC case) voice their
position. If we allow CSPs to send the shipborne data to the ASP based
upon any "format" or protocol than the ASP will have to absorb the cost
of supporting multiple "formats" and communication protocols. The extra
expense, of course, would likely be pushed back to the customers
(contracting governments).

This topic affects only ASPs and CSPs wishing to form the communication
path to the International Data Centre (not national or regional data
centers).

Based upon e-mails written on this reflector and the discussion in the
Hamburg meeting, the document will be aligned with the "consensus" view.

Regards,

Craig Hayley

System Engineer

Canadian Coast Guard

________________________________

From: ccglrit-gcclrit-bounces(a)lists.ncf.ca
[mailto:ccglrit-gcclrit-bounces@lists.ncf.ca] On Behalf Of Brian Mullan
Sent: Friday, June 01, 2007 10:37 AM
To: Hayley, Craig
Cc: ccglrit-gcclrit(a)lists.ncf.ca
Subject: Re: [Ccglrit-gcclrit] June 12-14 meeting of the Ad hoc Working
Group onEngineering Aspects of LRIT, Hamburg Germany

Thanks, Craig

Good clarification on the data format from the ships. However, you now
infer that CSPs will perhaps be asked to format messages from ships -
but not all CSPs have signed up to do this (I know of only one). It is
the understanding of many CSPs that the manipulation of the "raw" data
from ships starts at the ASP level. Also, the LRIT coordinator has said
in the past that coordination ("oversight") starts at the ASP level. The
CSP has largely been seen (until now) as purely the comms pipe that
provides the LRIT data from ships to the ASP and to start involving CSPs
in manipulating LRIT data would extend the oversight role.

Writing in specifications for all CSPs would therefore appear to be
premature!

Kind regards

Brian

Brian Mullan

Head, Maritime Safety Services

Inmarsat, 99 City Road, London EC1Y 1AX, UK

Tel: +44 (0)20 7728 1464

Fax: +44 (0)20 7728 1689

Mob: +44 (0)7711 495836

www.inmarsat.com

________________________________

From: Hayley, Craig [mailto:HayleyCR@DFO-MPO.GC.CA] 
Sent: 01 June 2007 13:52
To: Brian Mullan
Cc: ccglrit-gcclrit(a)lists.ncf.ca
Subject: RE: [Ccglrit-gcclrit] June 12-14 meeting of the Ad hoc Working
Group onEngineering Aspects of LRIT, Hamburg Germany

Hi All,

I'm please to see a good discussion has developed around this topic.
Hopefully, more discussion on other topics in the documents will be
initiated over the coming week before we meet in Hamburg.

Given the e-mails on this topic, the text (including wording in the
table) should be altered to eliminate any confusion.

I agree that the specific data elements (latititude, longitude, year,
month, day, hour, minute, unique equipment identifier) that the
shipborne equipment transmits is the important information. The "format"
of how those elements are displayed is accomplished by land based
software (not shipborne equipment software). Essentially, an application
piece of software will take those data elements, process them and
display them in a given "format". It has been decided that SOAP messages
(using XML format) will be the back bone of the LRIT communication
system. Thus, the various data elements contained in a given LRIT
message will have to be "formatted" as such. The question of whether
application software residing at the CSP or ASP (not software on the
shipborne equipment) begins to format the data elements into an LRIT
message (SOAP using XML) as defined in the communications document is
another issue. Currently, the document is written such that the CSP (for
the International Data Centre case) begins to build SOAP messages and
pass them to the ASP. We have to define an interface between the ASP and
the CSP for the International Data Centre case. If we allowed CSPs to
transmit information to the ASP using different formats, protocols, etc
than it wouldn't be fair to the ASP. This would add an extra cost burden
on the ASPs given that they would have to support multiple formats,
protocols, etc. Please note that national data centers and regional data
centers are free to define and allow different formats, protocols, etc
from the CSP to the ASP.

The intention of the LRIT communications document shall be to specify
the data elements transmitted by the shipborne equipment as stated in
Brian's previous e-mail:

Shipborne Data Elements:

Latitude -> degrees, minutes and decimal minutes to two decimal places
N / S 

Longitude ->degrees, minutes and decimal minutes to two decimal places
E / W 

Unique equipment ID -> number

Year -> 4 digit year number

Month -> 2 digit month number

Day ->  2 digit day number

Hour -> 2 digit hour number

Minute -> 2 digit minute number

Regards,

Craig Hayley

________________________________

From: Brian Mullan [mailto:Brian_Mullan@inmarsat.com] 
Sent: Friday, June 01, 2007 6:18 AM
To: Hayley, Craig
Cc: ccglrit-gcclrit(a)lists.ncf.ca
Subject: RE: [Ccglrit-gcclrit] June 12-14 meeting of the Ad hoc Working
Group onEngineering Aspects of LRIT, Hamburg Germany

Hi, Hayley

Many thanks for your email. I can agree that the text of the document is
clear; but that the wording in the table is not consistent and appears
even to contradict the text you quote. My copy of the document shows
wording for 1.1.1.1 that is different:

"The intent of this document is to outline the technical specifications
for communication within the international Long-Range Identification and
Tracking (LRIT) system as stated in the terms of reference of resolution
MSC.211(81)."

Your reference is new text in 2.2.2.4 in the copy that I received
(15-02-2007 LRIT ad hoc WG)

In Table 2, the heading indicates "Parameter provided by LRIT Shipborne
Equipment" and then describes the various elements, including specifying
the format. It is clear to me and others that this method of presenting
the information in the table means that the information transmitted by
the shipborne equipment *must* follow the format written in the table.
This is where the difficulty lies - the wording is over-prescriptive and
does not accord with the wording in 2.2.2.4. My original email showed
how, in Inmarsat C position reporting at least, the way the information
is transmitted. Other shipborne systems probably will have their own
format for presenting data to the ASP.

May I suggest, please, that we stick to requiring that the specific data
elements (unique identifier, latitude/longitude and date/time of the
position) are transmitted from the ship and then only start to prescribe
the format for onward transmission from the ASP? In other words, as long
as the shipborne equipment transmits, as a minimum, the required
elements, any format is acceptable. This allows for all approved
shipborne LRIT systems to be offered, no matter in which order or format
the data is presented. This approach will also allow the table to be in
accord with the new wording in 2.2.2.4

I hope that this is clear. Your hard work is very much appreciated and
it is clearly understood that the document remains a "work in progress".
Please don't take my input as criticism - it is not! All I seek is
clarity of the wording for all.

With best wishes

Brian

Brian Mullan

Head, Maritime Safety Services

Inmarsat, 99 City Road, London EC1Y 1AX, UK

Tel: +44 (0)20 7728 1464

Fax: +44 (0)20 7728 1689

Mob: +44 (0)7711 495836

www.inmarsat.com

________________________________

From: Hayley, Craig [mailto:HayleyCR@DFO-MPO.GC.CA] 
Sent: 31 May 2007 19:05
To: ccglrit-gcclrit(a)lists.ncf.ca
Cc: Brian Mullan
Subject: RE: [Ccglrit-gcclrit] June 12-14 meeting of the Ad hoc Working
Group onEngineering Aspects of LRIT, Hamburg Germany

Hi Brian,

Thanks for the e-mail. I hope more people will take the time to read the
documents and provide comments. I assume you are referring to the LRIT
communication document.

Please note the following text in the LRIT communications document: 

1.1.1.1          The parameters added by the LRIT shipborne equipment
include the latitude, longitude, Time Stamp when the position was
generated, and the shipborne equipment identifier. The "Format" of these
parameters as outlined in table 2 indicates how the parameters shall be
formatted while the information is contained within the LRIT message and
does not specify the format of how the shipborne equipment transmits the
information.

Regarding your concerns with the format of the date/time... The only
difference that I can detect between the date/time you state and what is
in Table 2 of the LRIT communications document is the separators ("-"
versus ":") for the year, month, day, hour and minute. The separator
used to separate the year, month, etc in the date stated in table 2 is
not important and in no way linked to the format coming out of the
shipborne equipment. The format is with respect to SOAP messages
communicated along the various LRIT communication segments. CSPs for the
IDC shall have to "build" SOAP messages complying with table 2 in the
communications document using the format from the ship borne equipment.
The important thing with the time stamp is that seconds are not
transmitted.

Regarding your concerns with the format for latitude... We had a
discussion on your e-mail and the intention was to implement your
recommendation. I can't recall why the "seconds" component of the
latitude didn't change to decimal minutes with a precision of 2 decimal
places. The most likely reason is that I forgot to incorporate this
change in the document due to the numerous requests. My apologies on
this topic. I will make the change for latitude to decimal minutes
unless someone raises a compelling reason not to change. Any body from
the Communications group recall if there was a specific reason why we
didn't make the change (Jilian, Guy, etc.)???

I would like to high light to everyone that these documents are in
constant flux as a result of many requests from different inputs at the
Ad Hoc meeting. Thus, it is important to fully read the documents that
come out of each meeting to ensure that any particular topic of interest
is addressed in a satisfactory manner.

Thanks,

Craig Hayley

System Engineer

Canadian Coast Guard

709-772-7740

________________________________

From: ccglrit-gcclrit-bounces(a)lists.ncf.ca
[mailto:ccglrit-gcclrit-bounces@lists.ncf.ca] On Behalf Of Brian Mullan
Sent: Thursday, May 31, 2007 12:35 PM
To: ccglrit-gcclrit(a)lists.ncf.ca
Subject: Re: [Ccglrit-gcclrit] June 12-14 meeting of the Ad hoc Working
Group onEngineering Aspects of LRIT, Hamburg Germany

Thanks, Tracy

In table 2 I note that the format of date/time is still shown as
YYYY-MM-DD-HH-MM. My earlier email (attached) made comment on this. Also
in Table 2, note appears to have been taken of my comments regarding
latitude/longitude position for Longitude only, but ignores Latitude.

We must not start requiring reformatting for transmitted data that is
already designed into existing shipboard equipment - PLEASE!

Many thanks

Brian

Brian Mullan

Head, Maritime Safety Services

Inmarsat, 99 City Road, London EC1Y 1AX, UK

Tel: +44 (0)20 7728 1464

Fax: +44 (0)20 7728 1689

Mob: +44 (0)7711 495836

www.inmarsat.com

________________________________

From: ccglrit-gcclrit-bounces(a)lists.ncf.ca
[mailto:ccglrit-gcclrit-bounces@lists.ncf.ca] On Behalf Of Peverett,
Tracy
Sent: 29 May 2007 22:27
To: ccglrit-gcclrit(a)lists.ncf.ca
Subject: [Ccglrit-gcclrit] June 12-14 meeting of the Ad hoc Working
Group onEngineering Aspects of LRIT, Hamburg Germany

Second of two e-mails

As promised, attached please find the updated LRIT Communications
specification.

Best regards

Tracy

Tracy Peverett

Senior Policy Analyst

Canadian Coast Guard

Tel: 1-613-990-4046

Fax: 1-613-998-3255

e-mail:  peverettT(a)dfo-mpo.gc.ca

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Re: [Ccglrit-gcclrit] June 12-14 meeting of the Ad hoc Working Group onEngineering Aspects of LRIT, Hamburg Germany