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As cellphones began to lose their headphone jacks, even Joe Schmoe finally discovered the wireless technology standard Bluetooth. It had been around since the 90s but only arrived in living rooms (and on billions of devices) within the last decade. And while this technology has been adopted by many, some users are still hesitant. Read on to learn what you should know about Bluetooth!
Where does Bluetooth come from?
In 1998, companies like Ericsson, IBM, Nokia and many others founded the Bluetooth Special Interest Group (SIG) to develop and promote a wireless technology standard that would allow inter-device communication via short-range radio frequency bands. The core technology was developed in a Dutch-Swedish cooperation, which is reflected in its name. "Bluetooth" is an anglicized version of the byname used for a Scandinavian tenth-century king thought to have either had a bad tooth that appeared bluish or a penchant for blueberries. He's also known for having been particularly communicative which fits the technology quite well. The well-known Bluetooth logo is a blend of his initials written in old runes.
How does it work?
Every Bluetooth device hosts a transmitter and receiver chip that operate on frequencies between 2.402 and 2.480 GHz, like many other radio-enabled devices (DECT phones, routers etc.). However, Bluetooth uses a special radio technology called frequency-hopping spread spectrum. It was co-developed by Hedy Lamarr, who gained popularity as a Hollywood star and the "world's most beautiful woman" during the Second World War. Back then, it was designed to steer torpedoes, today, we've found a more peaceful application. Bluetooth separates data into packets and sends each through 79 designated 1 MHz wide channels while hopping between them at a breathtaking 800 times per second. This improves both bugproofness and signal robustness against electrical interference from other devices.
The famous rune logo
What are the applications?
Bluetooth is often used in entertainment, control and communication systems like hands-free car kits but the technology has already spread to other areas. Many toys now feature Bluetooth, e.g. through accessories like game controllers or "smart" dolls that talk to each other. Alarm and security systems frequently use Bluetooth and so do key systems, prosthetics, hearing aids and insulin pumps. Along with WLAN, Bluetooth has already become the go-to technology in the industry to interconnect machines and computers. It is estimated there are now more Bluetooth-enabled devices than humans on our planet. Bluetooth is ideal when speed is secondary as the maximum bandwidth of 2 Mbit/s ranks far below that of WLAN or cable solutions.
Pairing
For security reasons, first-time connections between devices have to be manually confirmed through a process called pairing. For this to work, devices have to be placed in close proximity and pairing triggered manually, usually through a dedicated button on the device. Pairing a device with a PC requires pressing a software button. Each device is identifiable via a unique 48-bit MAC address and authentication often happens through a manually entered PIN code. Once paired, devices will reestablish the connection automatically the next time. Though Bluetooth is often considered a short-range technology, the actually supported range varies depending on the device class used and ranges from 100 meters (class 1) to less than 10 meters (class 3). Most consumer devices are class 2 or class 3 devices and, naturally, surroundings also play a role since walls may decrease signal strengths considerably.
Profiles
Bluetooth supports several data types through different profiles. For example, audio streams use A2DP while sensor data is transmitted via GATT. Depending on the use case, each device category supports a different set of profiles. Cellphones include multiple profiles, since they usually offer a comprehensive feature set (sending photos, telephony, headset connections etc.) while devices like temperature sensors are usually limited to a single purpose and profile. Some profiles implement special security mechanisms. For instance, devices like pacemakers or respirators , for instance, must provide a high degree of reliability so transmission errors are a no-go. The number of new profiles has been steadily growing ever since the advent of the Internet of Things (IoT).
Security
Apart from increased power consumption, which may have a negative impact especially on mobile devices, security issues have long dogged this technology. Experts still recommend users disable Bluetooth whenever possible and developers naturally took this advice to heart. Beginning with version 4 (2010), 128-bit AES-encryption was added to improve security. Still, there was (and still is!) the danger of unsolicited pairing. Usually, each pairing request must be manually confirmed, however, a vulnerability was discovered in 2017 that enabled attackers to connect without prior consent and access data or install malware. It didn't take long for updates to arrive but many devices like smartphones, cameras or toys are still using outdated Bluetooth implementations - so they remain vulnerable. U p to five billion devices are likely affected. The current Bluetooth v5 features enhanced signal penetration and increased speeds of up to 2 Mbit/s. Once again, security has been ramped up - as it has been for over a decade now. When (and if) Bluetooth will finally be a secure technology, is one of the more interesting questions. In any case, adoption rates will continue to rise as Bluetooth is just too handy and affordable a technology to give up!
What I would like to know: Do you use Bluetooth devices or do you stick with cables and WLAN? How has your experience been so far?
What about hifi?
Is quality still better with a top headphone physically wired ?
Yo la verdad rarísimamente uso el bluetooth asi que por esa parte estoy trankilo
One of the first lessons in Navy communications (radioman is the 'class') is a simple saying; "Whatever can be encrypted can be decrypted," part of the constant reminders we had on that ship (ComSeventhFlt is in charge of ALL troops stationed in the Far East, although that appears likely to change soon.
BTW, PBS recently aired a documentary, "Bombshell: The Hedy Lamarr Story". Such an interesting life and such a smart woman! She invented the technology for so many things but was never given her due.
http://www.pbs.org/wnet/americanmasters/bombshell-hedy-lamarr-story-film/9906/
Thanks for the lesson. As for myself, I would never use it! Whenever I buy a piece of tech, one of the first things I do is disable the Bluetooth. Security is one reason but the main one being health. I don't want that close to my body. For the same reason, I never hold my cell phone to my head and only use it with wired headphones. A thin wire is not such a drastic inconvenience to me that I am willing to risk my health and, though less so, security to eliminate it!
Thank you for the article. Learned the background of the software. I use Bluetooth often to transfer phone contents to the PC. Bluetooth is not dead. There is a BIG market for cheap portable Bluetooth speakers that consumers can use to play music from their mobile phones.
Hi Sven,
I have used Bluetooth since the early release, a company vehicle, cell-'phone with Bluetooth.
Connected to 'her indoors', (good wife) ....no problems and other family/friends without problems.
Do we need 'more' connectivity via A to Z technobabble, Skype to contact family and friends is great, not the 'Look At Me' egotistical Farcebook where every members' soul is sold to the Devil without reward to the individual zombie and their 2,137 'friends'.
A miniature, hand-held computer with an attached telephone, camera , messenger, browser of choice and office programme seems to be not enough for the masses to keep in touch with, 'The Rest Of The World'.
Bluetooth, under-rated and still going strong and what next in the future of communications............will it be possible to be "Beam Me Down, Scottie" into the lives of relatives, friends, 2,137 homes of Farcebook 'friends', as holographs.
Imagine if to will ...... the multiple implications of Holographic contact with family and friends ... they see you standing on their dinner table, do you click 'Accept or Reject'.
P.S. Text is words made of letters, text cannot be an action, texting is not a verb, sending a text message is a verb....., sending a written message using text, not graphics .... it seems the illiterate clones are merging.
Bluetooth is convenient but the radio frequency it uses is useless and dangerous as it is absorbed by water vapour in the atmosphere. It is the only spectrum of the Radio frequencies no one wanted to use because a strong radio emitter on a cloudy day would struggle to make a few km's. (1000's of km's for short wave).
Put an aquarium between 2 bluetooth devises, or better still your head. Trust me I use bluetooth headphones daily for gaming convenience and don't feel any different except my IQ seems to be noticeably dropping off and memory loss creeping in. I keep telling myself to cut back on the C2H6OH as my liver is showing problems. (Can't process the alcohol quick enough and I fall over a lot) A bad liver gives that effect poisening the brain. Could I be wrong and its prolonged bluetooth use?
A year ago my doctor told me my LDT liver function levels are within specifications.
The bluetooth signal probably radiates away from the headphones in all directions for about 10m so as the signal is weak I should be ok.
No medical research has proved it to be dangerous in the long term, as we have to wait another 20-50 years. Perhaps that's the problem aging!!!
Makes you think though. I will be using the headphones again tonight...
Regards.
A few months ago I bought a Bluetooth wireless headset for use with my laptop. It works in conjunction with a Bluetooth USB dongle on the laptop. Three times it suddenly stopped working and no matter what I tried I could not get it to work again. So each time I had to bring my laptop back to BestBuy and get one of the geeks to get it working again. Now for the fourth times it has stopped working and I'm seriously in doubt about whether to make a fourth visit to BestBuy or call it quits and buy a traditional Sony non-Bluetooth wireless headset.
Thanks for a clear and very well written article. I use Bluetooth for speakers, phones etc. but was unaware of the security vulnerability.
Thank you Sven, for your blogs. Enjoyable and educational.
You’re welcome! I thoroughly enjoy writing these articles as I always learn a lot in the process. :)
I can't pretend that I fully understand your technical explanation of the inner workings of Bluetooth, but I certainly use it to connect my mobile phone to my car, for hands-free use. I find it very useful, very reliable and very effective.
Generally speaking, I find that Bluetooth sucks. I use it under protest. My Bluetooth speaker has difficulty connecting if I haven't connected in awhile. In my car, the phones have started to be crackly. The whole connection thing just seems to be hit and miss. Maybe, it's just me.
I have used Bluetooth for many years. My friends and I would send ring tones. Here as of late, I have really enjoyed the wireless headphones and others. Also I have added the use of keyboars and mice. I really like the technology.
Have used for probably ten years with phones back to the Razr flip phone. Never used with desktop, rarely with laptop, some headsets, speakers, no mechanisms.
Hate wireless, give me a cable any day.
ok I am not a tech head.....however to answer your questions: I love Bluetooth used with extension speakers (Bose) used with say my laptop. I use cables with my desktop computer in preference to Wi-Fi. as far as I know WLAN is a function used by my Router. this is all the info I can give you. regards, Arnold Smith
For devices at home bluetooth is great for very short distances but I mainly stay with cables and wlan. Bluetooth is still too insecure of a tech to use out in the general public.
thanks for this info as I was unaware of the dangers
I stick to cables.
Thank you for this "lesson". I discovered Bluetooth 20 years ago, but now I use it, and I know how it works.