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Data Link Modes

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Jack View Drop Down
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    Posted: 03/July/2017 at 21:36
You've probably seen this on the Facebook group, but, to
start off the newly re-instated Forum, I'm posting it 
here as well for those who don't play on Facebook.

-------------------------------------------------------

Now, here's a possible theoretical scenario, you are contacted by your 
head of the Civil Contingencies department.

"We are having an exercise this weekend involving a large
scale flood evacuation, we need you to set up data links 
from 4 rest centres to the Operation Control Room.
We need you to pass lists of evacuees, equipment 
requirements etc.

There will be no telephone or internet available due to 
the Telephone Exchange being flooded, and there could be 
the possibilty of mains electricity failure."

How many groups could fulfill this requirement, what 
data modes would you use, and how many of your members 
have the capability to set up such a station ?.
G8HIK Bolton RAYNET
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Post Options Post Options   Thanks (0) Thanks(0)   Quote M0RYK Quote  Post ReplyReply Direct Link To This Post Posted: 18/July/2017 at 11:57
I think you pose one of the fundamental questions about RAYNET. Are we cheap telecoms providers, or are we comms problem solvers, whose job is to deliver practical, outcome based solutions. Frankly, if we're not the second, we're no longer in the game.
So, with great respect, don't be pushed into platform/ channel based solutions. Comms challenges should be outcome led, not platform led, and user services should be told that. Below, I've answered your questions in passing, but I've tried to address the real issues for the purposes of debate.
In the circumstances you describe, establishing resilient command and control and co-ordination are absolute priorities for RAYNET, let alone anyone else. And given the potential nature of the mass data traffic, multiple radio data links are not the best solution, given set up times, nature and volume and potential sensitivity of the mass data, and the need for reliable traffic handling. My suggested strategy and solutions would be this
1. First, command, control, co-ordination. So voice channels first, because unless you're in a metropolitan setting, fixed AIrwave talkgroup and channel capacity will be clogged.   So do you have the pretty simple necessary kit, and practised operators, with good net and message handling and recording disciplines?   We've got these, and they hone their skills on event after event, just like groups everywhere. Sorting this also sorts the routing for short, sharp equipment requests. Your voice network is also the vital precursor for dispatch notification and tracking etc - see below.
2. Mass data handling. Lists of evacuees means a lot of personal data that needs consistent, accurate and preferably reasonably secure transmission. A slow speed, open, data net with multiple stations is no solution. This problem requires either physical transmission or resilient, standalone IP solutions. So either
- 12v satellite terminals with satellite internet access and local wifi or Ethernet connection. (Yes, we can do it, and have done it.)
- or stand alone Mesh networking. The Scottish groups working across the Firth of Clyde have shown the way, as have others, but terrain and distances are a factor.
- or 4x4 or motorbike couriers (e.g. 4x4 Response, police, accompanied tspontaneous volunteers etc ) ferrying numbered USB memory sticks - relatively fast, secure and robust, no transmission channel probs; trackable, verified delivery, etc. (Obviously. rest centres and ops centre are accessible by road.) The user services need only simple computer facilities, and consistent data formats, or even just pens and paper, powered by good old fashioned wetware. Your voice Net guys are there to help arrange, track and verify delivery etc.
Of course, I confess to the crime of creating and answering a different question - but arrogantly and selfishly I think it's the right question. Thanks for stimulating it.


MIke M0RYK / F4VRD
Co-ordinator, Kent County Raynet
RSGB Emcomms Committee member for the South East
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Jack Quote  Post ReplyReply Direct Link To This Post Posted: 18/July/2017 at 17:42
All interesting stuff mike, my preference is bog standard
packet radio, it's easy and quick to set up, the kit is
inexpensive these days, and the learning curve is very shallow.

1200 Baud is perfectly capable of handling the sort of
messages in the above scenario, and if needed, can be made
secure.

The vast majority of emails are plain text, and there
are millions of plain text messages sent every day
from mobile phones, and plain text is what Packet
excels in.

The control station can run a mailbox, into which messages
may be deposited for processing.

The same radio can be used for voice and packet, if you
have a good voice link, you have a good packet link, if the
link is poor, then you can digipeat via another station.

I'm a great believer in KISAC, (Keep it simple and cheap).
the simpler and cheaper it is, the more people you are likely
to get involved.

It's a tried and proved technology, and has been used extensively
by RAYNET in the past.


Jack.

G8HIK Bolton RAYNET
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Post Options Post Options   Thanks (0) Thanks(0)   Quote M0RYK Quote  Post ReplyReply Direct Link To This Post Posted: 18/July/2017 at 18:37
Fair enough, Jack. I admit to some scepticism about packet delivering security, rather than privacy.   And given the nature of the potential traffic, and the great variation in real life of rest centre arrangements, staff and capabilities, I'd still be more comfortable if mass personal data travelled by courier. But I'd be happy to be proven wrong.
73
Mike
MIke M0RYK / F4VRD
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Post Options Post Options   Thanks (0) Thanks(0)   Quote G1HUL Quote  Post ReplyReply Direct Link To This Post Posted: 18/July/2017 at 18:44
There are packet "email" clients that look like standard email systems (so easy to use by non-radio people) and support PGP encryption.

Can't remember their names, used a lot in the US by ARES.
Jim, G1HUL
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Jack Quote  Post ReplyReply Direct Link To This Post Posted: 18/July/2017 at 19:07
There are plenty of encryption programs out there that can be used in conjunction with Packet, so security isn't a problem, although the licence conditions are quite strict, re encryption.

The original question was, how would RAYNET deal with the scenario, as far as I know, RAYNET doesn't run a courier service.


G8HIK Bolton RAYNET
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Post Options Post Options   Thanks (0) Thanks(0)   Quote M0RYK Quote  Post ReplyReply Direct Link To This Post Posted: 18/July/2017 at 19:48
Raynet might not run a courier service, but in this county, and I presume elsewhere,, we always work with people only too willing and able to help, like 4x4 Response - a lot of whom also have amateur radio licences, incidentally. I always find that drawing them in improves relationships no end.
I agree about the licence conditions. Ofcom's guidance is very specific in parts, and utterly ambiguous in others - the incident commander has to request the use of encryption for specific messages. One section says we're not allowed to send encrypted materisl international borders. But another says If there's a likelihood of messages being sent or heard across an international border (inevitable in NI, and quite a lot of the coast in the S E, Etc) there are logging requirements, because encryption is a breach of the Radio Regulations. Endless fun .....
MIke M0RYK / F4VRD
Co-ordinator, Kent County Raynet
RSGB Emcomms Committee member for the South East
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