SpreadNet Spread Spectrum - still viable?

I am replacing an old Brinks BHS-2000D based system that uses wired and wireless sensors and evaluating what I can reuse for a replacement system which is likely to be Vista20P or Vista21iP based. I am only interested in alarm and fire, no interest in IoT/control. I will be trashing the panel, keypads and 4-wire smoke. This leaves the following:

1. 3x SpreadNet wireless SN-935DT DualTec motion sensors
2. 2x SpreadNet wireless door sensors
3. 1x SN914-SZR Spreadnet receiver. I don't have an SN-900 Prog programmer but these crop up on eBay occasionally if I need one.
4. 4x wired DT-435TB DualTec motion sensors (need to check for EOLR but this was after-market install)
5. 2x wired external door sensors
6. 1x overhead garage door sensor

It seems likely I can re-use all the wired sensors but of course most of the original cost and most of today's replacement cost would be in replacing the wireless components since I would again select DualTec motion sensors which are ~$120 each. Hence request. Couple of data sheets attached for reference.
 
Thanks
John

Why use a third party RF when the Vista has one of the best wireless receivers and device selection on the market.
 
The BHS system, if a Honeywell product (not scantronic) uses all Honeywell 5800 series devices and the receiver is the same.

If the can hinges top/bottom, it's scantronic. If it's beige, it's Honeywell

Sorry, I see I didn't make it clear in my original post. The reason to use third party is because I already own these sensors.
 
To replace with Honeywell 5898 (which is the option I am considering if I cannot reuse what I have) would cost $120 per sensor i.e. $360 for three. And once I switch to the current Honeywell wireless system then every other wireless part will need to change because Honeywell use 345MHz while my sensors use 902-928MHz spread spectrum comms (or they should be but see below). So probably approaching $500 I wouldn't need to spend if I can reuse.
 
As to what I have now. There's a Scantronic label stuck on the side of the can that hinges at the top so it seems fairly certain the can is Scantronic. The printed label inside the cover with a diagram explaining the connections indicates BHS-2000D but the online ADT system lists my alarm as BHS-4000D and indeed the back of the PCB seems to confirm this based on the part number stamped there so it must have been replaced way back when there were some problems with the system. I guess I'll need to power down and open up everything to check exactly what is there in case anything else was changed.
 
The SpreadNet spread spectrum was made by C&K which became part of Ademco/Honeywell. I assume today's Honeywell dualtec leverages some of that history, but today's sensors use different frequencies for the comms and for the microwave.

If the RJ cord is direct connected to the board and the can opens up top to bottom, then you got a scantronic unit. Basically it's sounding like you hae a boat anchor.
 
I'd ditch the wireless. Appears the unit is only able to trigger a single relay/zone, so really, it's not in your best interest to keep it or migrate it to the new panel.

Well I now have the answer to my question "Spreadnet Spread Spectrum - still viable?" and the answer is no, but not for the reasons I had originally considered. In a good news-bad news story I've discovered that back around 2008 Brinks basically gutted the complete alarm system. In the course of which they removed my spread spectrum (bad news) door/motion sensors and wireless receiver, replacing them with Honeywell 5800 series sensors (good news).
 
Its bad news because I paid a premium for spread spectrum to mitigate wireless jamming (however slight that risk) and instead ended up with vanilla Honeywell 345MHz (without my knowledge or approval) that enterprising DIY'ers seem to have reverse engineered the protocol on, in order to use the sensors for home control projects http://www.rtl-sdr.com/reverse-engineering-honeywell-345-mhz-home-automation-sensors-rtl-sdr/
 
The good news is that after opening up all the sensors and wireless receiver it seems I have Honeywell 5897-35 DualTec motion sensors and 5816 door sensors so I should be able to reuse these with either a 6160RF keypad or more likely a 5881ENL receiver in a replacement system. The old wireless receiver is BHS-3250 and based on some internet searches appears to be proprietary so it will be binned along with the two proprietary Brinks keypads and BHS-4000 alarm panel.
 
Just for reference. At the same time Brinks changed the wireless sub-system they also replaced the alarm panel. Hence why the Honeywell based BHS4000 PCB (Honeywell 2007 etched in copper on the PCB) is contained in the Scantronic can.

I don't see the how the C&K devices and receiver are attractive or a better product than the 5800 series in this application.

You are correct that in my situation today the C&K devices and receiver wouldn't be better because they might be difficult if not impossible to tie into a Vista system. Hence why the Honeywell 5800 sensors Brinks left me with do actually work out better for me today because I should be able to integrate them with Vista.
 
That said, in general spread spectrum is a superior technology to a fixed frequency comms. Fixed frequency is easier to detect and then to jam. Spread spectrum is much harder if not impossible to detect and jamming would require saturating a band of frequencies assuming you knew which frequencies to jam in the first place. That's why I chose the spread spectrum solution back in 2000 when the system was originally installed.
 
Its certainly debatable as to whether one needs the sophistication of spread spectrum and/or encryption, the vast majority of crimes seem to be simple smash and grab. However, the ability to detect and decode Honeywell's protocols on 345MHz does make the 5800 series more vulnerable to a sophisticated attack, and failing that someone could just jam the frequency. The company Videofied, now owned by Honeywell, implemented both spread spectrum and encryption to address these threats. It costs relatively little to implement this more robust wireless comms based on the Videofied prices so in my view it should be standard practice to build into wireless alarm systems. Honeywell's SiX system just implements encryption. 

This doesn't help your application needs now but wanted to just mention that Honeywell does have new SiX Series sensors that work with their new Lyric system. The SiX Series sensors are encrypted and use spread-spectrum technology.

I've heard they are in the works to make a SiX Series RF receiver as well so that a VISTA system could employ the more secure wireless sensors.

Thanks for the feedback Sterling. I hadn't seen any mention of spread spectrum on the SiX sensors before, only the encryption hence my statement so your confirmation is useful. Is the spread spectrum discussed in any SiX documentation I can reference? I confess I had only briefly skimmed some of the SiX documents and hadn't seen spread spectrum mentioned.
 
The potential future upgrade of the wireless section of a Vista system is a nice option.

I can't find any documentation from Honeywell specifically saying "spread-spectrum" and perhaps I'm mis-using that term but I did find the following from their internal site which I believe would be your verification that someone jamming a frequency channel would not prevent the devices from getting back to your panel. Please correct me if I'm wrong.
 
The Panel will monitor the Wi-Fi and 802.15.4 RF environment, If noise or an overlapping channel is detected, panel will initiate a change and select a new channel with less interference and direct all sensors to join that channel. The Panel will change channels and verify all sensor made the change. If any sensor did not join the new channel, the panel will tell all sensors to rejoin the previous channel, and repeat the process.

Sterling,
Don't take my answer as gospel but as I understand it the Honeywell Lyric system uses WiFi and Z-Wave wireless technologies. What I believe you to be referencing is how to counter interference on the WiFi or Z-wave channel and not the application of spread spectrum technology. For example interference could be a number of sources, such as microwave ovens affecting WiFi or just your neighbors using the same WiFi channels. The section you quote seems to be selecting another available WiFi channel to try to either mitigate or avoid the interference. Ditto for Z-Wave. Spread spectrum deliberately selects and varies which frequencies it uses in anticipation or attempts to disrupt or monitor its communications, which is different. Concept explained here https://www.videofied.com/us/en/concept/secure_wireless_communication/

I found some more documents I had about SiX technology and they do say SiX devices employ "direct sequence, spread spectrum (DSSS), two way radio" technology.
 
The sensors aren't actually WIFI back to the panel. They use a proprietary Honeywell RF technology that uses the same 2.4GHz range used by WIFI devices.

I couldn't find Honeywell promoting spread spectrum publicly with either their Lyric panel or the SiX sensors that communicate with it. Maybe they believe that their end customers might conceptually understand encryption but would just be confused by discussion of spread spectrum. Clearly Videofied felt differently by actively promoting both on their website. In the Videofied case they appear to be using Frequency-Hopping SS based on the animation on the website versus Direct-Sequence SS in the SiX sensors.
 
While I couldn't find any mention online for Honeywell Lyric/SiX use of spread spectrum beyond that of another forum and a provider of alarm equipment, I did find a nice 4-page whitepaper from Honeywell Process Solutions titled "Interference and Security Considerations for Wireless Communications in an Industrial Environment" that briefly compares some of the options including a comparison of FHSS vs DSSS which some readers might find of interest  http://www.honeywellprocess.com/library/marketing/whitepapers/Interferenceand Security_WP_May08.pdf
 
Edit to fix link

Hmm, I read that whitepaper (very interesting find by you!) and still am unclear about which type of spread spectrum technology would be less susceptible to jamming and interference.
 
I would think if the sensors can hop from one frequency to another (like with FHSS), that would be less susceptible to frequency jammers but I also know nothing about how frequency jammers work and I also may be understanding it wrong as the chart at the bottom seems to read that DSSS is less susceptible to interference and jamming.

I agree that the table isn't very well worded. Where the table column header says "Susceptibility to jamming & interference" it would probably be better titled something like "Ability to counter jamming & interference" and a rating of 5 means FHSS is best which is consistent with the statement in the article that "With FHSS, security and noise immunity are at a peak". The article also states earlier that narrow band is bad for susceptibility to jamming and interference; and both the narrow band solutions have a rating of 1 in the table which is consistent with poor comparative performance.
 
There may also be some factor at play based on which frequency band is used, i.e. is there more general non-malicious interference in the 2.4GHz or 900MHz frequency band, I'm assuming that wasn't part of his assessment but the author didn't specifically exclude this.
 
In any event while FHSS seems to have an edge, both forms of spread spectrum appear to be much more attractive from a security perspective than standard narrow band based on this authors ratings.