How commercial Radio System are protected for People who want have some "fun"? - Page 1
Forum section: electronics / rf-microwave

author: Lord of nothing
author_rank: Super Contributor
timestamp: April 22, 2020, 06:45:34 pm
content: HiHere in my City the major Public Transport Company run a Analogue System and the Broadcast Messages are on one Freq Analogue who from time to time People with some kind of Mental illness scream disturbing thinks into there Radio who get broadcast around the city.Well what is when the Public Transport Company would switch to an (unencrypted) DMR, NextEDEG, Tetra,... System?What I heard Tetra could use some Authentication with a Sim Card.How about DMR? Does the Repeater have some kind of Authentication?How are the protected from "Capture" them with a total new User Group who the "legitimated" Radio not know and not show.

author: geggi1
author_rank: Frequent Contributor
timestamp: June 10, 2020, 07:19:46 pm
content: This reply is a bit late.Motorola DRM (Mototrbo) have the capabilities for AES encryption. It is posible to buy licences for higer grade of encryption.Mototrbo does also have the posibility for internet linking saving some cost for an permanent analoug line.Hytera does also have enctyption capabilities with the option of bying licenses for higher enctyption grades.By using TS1 & TS2 on the repeater is is possible to have two paralell speach channels on the same frequency pair.I think it is also possible to have a whitelist of radios so that it its not possible to get a transmission through the repeater. Jaming of the input frequency is possibible.As far as I know many of the Chinese cheep brands do also have encryption but I guess it is a bit like huawei with possible backdoors.TETRA does have the capabilities for very high level of encryption but price for terminals and repeaters are 2-3 times higher than for a DRM system.But it is also possible to have 3 paralell speach channels (one TS for handshaking and net control)

author: vk4ffab
author_rank: Frequent Contributor
timestamp: June 10, 2020, 09:54:01 pm
content: Quote from: Lord of nothing on April 22, 2020, 06:45:34 pmDMR in amateur radio does not require authentication. But what it has going for it to stop random people from using it is obfuscation. I guess the same goes with commercial DRM, without knowing the time slot, colour code and channel names and or what network to connect to, its pretty hard for some random person to jump on there and cause problems. DMR is not like going and buying a baofang and being able to annoy people, it requires some work to setup and use and you need all the technical details to do so. Just setting up DRM for amateur radio use is kind of a nightmare. LOL

author: geggi1
author_rank: Frequent Contributor
timestamp: June 10, 2020, 10:36:08 pm
content: DMR is a commersial standard defined by ETSI but it has been adopted for HAM use.

author: Marck
author_rank: Regular Contributor
timestamp: June 11, 2020, 10:37:47 am
content: TETRA you need to line up the holes to get through. Valid radio ID on the system. Valid Talk group id. Valid system id and country code. And thats if the system is clear. When you stack all these things up it gets well beyond the mental capacity of the twits that play those silly games.DMR is much the same once its any harder than throwing in a frequency on a $30 Chinese radio people that can do it just don’t.

author: Lord of nothing
author_rank: Super Contributor
timestamp: June 11, 2020, 04:08:57 pm
content: Quotewell anyone can program anything into any dmr radio so that is no problem to pass that.QuoteNobody found any Backdoor in any Huawei Product until today. On the other Hand the US Company Cisco Products have one.QuoteWhat I read the have 4 Speak Channels.QuoteWith Simcards who I know. So its quite impossible to send fake Radio Data into the System.QuoteDSD Plus show everything.QuoteWell its no problem. There is nothing special about that.QuoteSure because there are no information about that. Its just guessing. Sry like many open source stuff its often turn into a nightmare because nobody fell capable for the project.QuoteMany of that thinks are open Source now:Code:T-MNC232-1000-TETRON Sicherheitsnetz Errichtungs- und BetriebsgmbHHohenbergstraße 1 / Objekt 3A1120WienT-MNC232-1010-Büro der Vereinten Nationen WienWagramer Strasse 5A1220WienT-MNC232-1020-OMV Austria Exploration & Production GmbHProtteserstrasse 40A2230GänserndorfT-MNC232-1050-Wiener Lokalbahnen GmbHPurkytgasse 1BA1230WienT-MNC232-1234-Flughafen Wien AGFlughafenA1300Wien-Flughafensource:https://www.rtr.at/de/inf/odSKP232-1234 is use by the Vienna Airport232-1010 use by the United Nation in Vienna ()And 232-1000 by the "Company" who maintain the System for the Fire, EMS and Police

author: Theboel
author_rank: Frequent Contributor
timestamp: June 11, 2020, 04:21:45 pm
content: Hi,My city Fire rescue has same problem and they solve it use IP-Radio.in this case they must pay about 5 USD for each radio a month (GSM subscriber fee) and about 100 USD for the hand held.

author: Lord of nothing
author_rank: Super Contributor
timestamp: June 11, 2020, 04:57:08 pm
content: QuoteUntil the power ent out and no network coverage.

author: geggi1
author_rank: Frequent Contributor
timestamp: June 12, 2020, 01:52:06 pm
content: No TETRA got 4 timeslots one is used for roaming and the rest for data or speach. But if the configuration is "sigle site multiple repeater" or "multiple site multiple repeater" you will have four timeslots for each repeater minus one timeslot for the whole site used for roaming.