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I'm doing a research about Bluetooth and I'm not sure what is the bluetooth maximum bandwidth?
I've seen that bandwidth is measured by Mbps and I've only seen Mhz... Help please
Before talking about the bandwidth of Bluetooth, let's learn about the technology behind Bluetooth. Bluetooth is an old technology for connecting two electronic devices without any wired connections. We can transfer the data packets from one device to another device with the use of radio waves. Every electronic device (which supports Bluetooth) consists of Bluetooth adapters, which are used for sending and receiving data. And we can only send the data packets only when the two devices are within the range(Bluetooth range) of each other. As the Bluetooth principal rule is to work on radio waves, we measure the frequency of Bluetooth on MHz, not on Mbps. The most common application of Bluetooth is: "Laptops, Headphones, Mobiles, printers and many more electronic devices...". Most of the electronic applications work on 2.4 GHz. The maximum range of Bluetooth is around 350m.
I think the above information might be a bit helpful for your research.
Thank you.
I believe you are mixing throughput with bandwidth:-
Throughput is the amount of data that can be sent per unit time. For this, the unit of measurement is bits per second (bps).
Operating frequency on the other hand is the frequency at which a wireless technology operates. The unit for this is Hz, and Bluetooth generally operates at 2400MHz - 2483MHz.
I recommend the links below to understand more the difference and how they are used programmatically:-
Classic Bluetooth vs Bluetooth Low Energy
Bluetooth 5 Speed: How to Achieve Maximum Throughput
A Practical Guide to BLE Throughput
The Difference between Classic Bluetooth and Bluetooth Low Energy
Introduction to Bluetooth Classic
Getting Started with Bluetooth Low Energy
The Basics of Bluetooth Low Energy
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I am building some software on mac os x that uses iobluetooth and corebluetooth to connect/manipulate bluetooth devices.
Like most Bluetooth speakers, the Bluetooth classic network is hidden unless pairing but often the Bluetooth Low Energy network is visible.
I was wondering if there was some way to find a link to the Bluetooth classic section through the Bluetooth Low Energy network and use the details to establish a connection to the Bluetooth classic network.
I am assuming that your speaker is supporting both LE and classic Bluetooth profiles.
So you can connect le first by giving BD_ADDR and all the details for your speaker and later on you can change the transport to classic Bluetooth such as A2DP or SCO.
Thanks.
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I want to monitor bittorent traffic in my LAN. I used wireshark for that. But I couldn't able to find packets by using wireshark. But can monitor with UDP port number
we can use colasoft packet analyzer. It helps to monitor P2P traffic. Since Skype uses p2p.
Visit http://www.colasoft.com/.
Yeah, I agree. One of Colasoft Capsa 7.8's new features is VOIP analysis.
Below is what I found on their site.
"Capsa 7.8 provides a VoIP analysis module to capture and analyze VoIP calls and graphically display VoIP analysis results, which helps IT staff baseline and troubleshoot VoIP-based networks.
A VoIP view is provided to list all VoIP calls as well as their related statistics and has a lower pane for analyzing voice and video control flows and media flows as well as their jitter, loss, MOS, etc., to visualize analysis data and assess voice and video quality."
source: http://www.colasoft.com/capsa/whatsnew.php
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I have a bluetooth device (headphones) that supports playing audio over A2DP.
I've been pairing them with both an iPhone and an Android, and I get only extremely poor audio quality with both sources.
My suspicion is that the device only supports the SBC codec, but not Mp3. Or if it does MP3, only an abysmally low bitrate.
The manufacturer only states A2DP is supported, but not which codecs.
How can I determine which codecs are supported? Is there a kind of protocol sniffer I could use on my phone or my computer and interrogate the device to get a definitive answer on what it supports?
You can actually see used A2DP codec in iOS device's console.
Step-by-step guide:
Connect your iOS device to your Mac, answer Trust on the iOS device if you haven't done this before.
Open Console.app.
Select your iOS device on the left sidebar.
Type bluetooth in the top-right search bar, press Enter and select Subsystem instead of All:
Now, start playing to your bluetooth headphones on the iOS device (codec activates only when you output sound).
Press Cmd+F and search for Starting a2dp send thread in your console messages:
You'll see used codec in codec: field. Values are the same as specified in Bluetooth specs (example). Basically 0 = SBC, 2 = AAC.
Was very surprised, though, that a pair of headphones I just bought from very adored and award-winning manufacturer (not Sennheiser) does not have AAC codec in them, despite having that in specifications (will not name them here, contacting their tech support for clarification).
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I have a Linux box wich has several 10 Gbe interfaces. What I want is to make a crypto-tunnel that has an ability to process 10 Gbit/s traffic as well as 10 Gbit/s router/firewall. There are some ways to achieve this but as I see it all the ways are brings to user-space or kernel-space processing.
As for the user-space solution, I suppose TUN/TAP device. But my experiments shows me that single TUN-device has performance limit at 1 Gbit/s boundary. I try some kind of TUN's aggregation and it gives me about 3.5 Gbit/s on 8xCPU XEON configuration (w/o encryption thought)
As for the kernel-space solution, I suppose that it might be faster than user-space, but it has another degree of complexity....
Has anyone has knowledge of how to make 10th Gbit/s Linux-based VPN solution?
UPD #1
Software solution wanted
TOE (TCP Offload Engine) is both your friend and enemy here.
TOE is the network card equivalent of a GPU from a graphic card along with something like DMA (Direct Memory Access) used by old style hard drive controllers. It allows for offloading the work of the TCP/IP stack to the NIC instead of running it through motherboard front side bus and CPU which are bottle necks for data being processed at this speed.
In order for what you are asking to work you will need your 10Gbps cards to have TOE (hardware acceleration) enabled in the OS and drivers. I worked on a project similar to this using a Cisco Nexus switch and some $5500 NIC cards about three years ago so I'm a little out of date on the technology. I'm betting things have moved along and costs gone down.
If you have already solved the TOE issue, then ignore my response.
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Not sure if this is a Stack Overflow question (if anyone knows a more apropiate section of StackExchange I'll be happy) but all questions on NFC Readers seamed to be here so, here I go:
I want to use NFC-Tags for a project and need a reader. While more and more phones are capable of reading such tags, any older phone is not. These phones do however usually have Bluetooth. So what I am looking for is a NFC Reader that can connect to a phone via Bluetooth.
I thought this would be a common device but to my surprise I did not find much. Readers usually connect via usb (as these do). There is at least one device that does use Bluetooth, the Blueberry UHF, but I could not find any retailer that sells it.
So, my question would be this: Is there a reason that there are almost no such devices or am I just looking at the wrong places?
I know I am late answering this questions, but maybe my response will help others who are searching for the same thing. What you are looking for is available from Serialio. There are multiple Bluetooth NFC readers available. The BlueBerry is re-branded with the Scanfob brand.
Here is a link to the updated Scanfob NFC page (the above link posted earlier no longer works): https://serialio.com/products/rfid/readerwriters/scanfob%C2%AE-nfc-bb2
There are multiple apps available that interface with the readers. This really depends on what you want to do with data from your reads.
Heres' an example of attendance managment solution using an NFC reader on Android:
https://serialio.com/products/mobile/software/MobileGrid/Android/use/TimeTrack/MG_TimeTrack_Android.php
There's a lot more. I just don't have the reputation to add more links yet.
The type of device you refer to is available here: https://serialio.com//store/index.php?cPath=89&osCsid=nep7av4i0431r39eqdl23oh2i7.
The reason you struggle to find a Bluetooth enabled device is because the peripheral market for NFC/RFID readers are targeted at the desktop embedded market where USB/RS232 cable options are cheaper/easier/stable offerings people are familiar with. The driver stack provided with a cabled device can also do a lot of the hard work in dealing with the incoming data.
There are however a few companies on the market producing RS232 to Bluetooth bridges which means you can try and port peripherals across to this using Bluetooth. Although you'll be able to pair the devices, you'll then need to write the software that can interrupt in the incoming payload over the Bluetooth serial port connection so it'll be a lot more work to get a platform like this up and running - especially with older devices. However it is possible if required.
What possible problem would a NFC reader that connects to a phone via bluetooth solve? The phone is not going to know anything about NFC, it does not have the required software or stack.
Sure, you could write that software (possibly) but to what end? The unit you linked to is what you are after, sure, but it's for a very specialised purpose (i.e. you have to write the s/w at the other end).
It's likely to be cheaper (in time and money) to just buy a phone that supports NFC rather then trying to upgrade a unit that does not.