Please clarify a few questions regarding the below scenario -
A service provider is providing a business "ABC Limited" two PRI trunks on a single IAD.
Should the IAD be always a 48-port IAD or could it be a 24-port IAD?
Assuming it's a 24-port IAD, what I'm unable to understand here is that if the device has only 24 ports then how will it allow 46 simultaneous call?
Is there any limitation placed on the number of analog telephone devices that could use a single IAD assuming a PBX is used between IAD and telephone devices?
Can the IAD be used without a PBX? If yes, then what should be the total number of analog telephone devices that could be attached to the IAD?
I provide a brief overview of an IAD below that will help clarify the answers to the questions posted.
Should the IAD be always a 48-port IAD or could it be a 24-port IAD?
Hardware-wise, the provider will provide a Voice handoff(Analog or Digital, PBX or Analog phone) and this will depend on the Data Pipe being installed. As an example, utilizing Telco Data, a 1.5 Meg T1 with 24 ports allowed for Voice channelization, if ALL ports are in use, this will utilized ALL the Bandwidth and not allow for any data to be used. So, 48-port IAD can be configured, only if the Data Pipe being installed is (2) bonded 1.5 Meg T1's.
Assuming it's a 24-port IAD, what I'm unable to understand here is that if the device has only 24 ports then how will it allow 46 simultaneous call?
You are correct. You will only have 24 voice channels available in a 24 port configuration. The handoff can be to a PBX can be Analog Trunks(can have analog telephone devices connected to these) or a PRI protocol.
Is there any limitation placed on the number of analog telephone devices that could use a single IAD assuming a PBX is used between IAD and telephone devices?
When talking analog telephone devices only, then, a 1 to 1 ratio has to be considered in the case of an Analog Trunk handoff.
Can the IAD be used without a PBX? If yes, then what should be the total number of analog telephone devices that could be attached to the IAD?
Again, in an Analog Handoff, a 1 to 1 ration is what you will need to consider.
NOTE: Integrated Access Device (or IAD) provided by the Local Telecom Provider can be deployed with multiple configurations. Its primary purpose is to aggregate multiples channels of data to support Voice and Data services to a carrier or service provider using one Data pipe onsite. When no Voice Channels are in use, the total capacity of the pipe can be utilized for Data.
Dynamically, the pipe will allow Voice channels(or ports) to be available when requested by the PBX onsite/analog device attached to the IAD or when an PSTN caller dials into the PBX/analog device. The Data Pipe will dynamically adjust to allow less Data to be used on the shared pipe to allow the Voice Channel connect. This is approximately 64k of bandwidth PER Voice Channel.
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i want to know some details about iBeacons. Couple of days back i created a sample project where i turned my iOS Device into an iBeacon and i tracked down that iBeacon with another device, i am also getting the proximity distance between my Device and the beacon.
So my question is Is it possible to post some advertisements from my device which acting as iBeacon?
How to configure that?
All i wanted to know is how the iBeacon Configuration done to send the data?
Some one please help me out
thankYou
An iBeacon "advertisement" is just a constant transmission of a four part identifier that signifies a unique device. It only contains four fields:
proximityUUID (a 16 byte UUID usually expressed in the form 00000000-0000-0000-0000-000000000000)
major (a number from 0 to 65535)
minor (a number from 0 to 65535)
power (a number from 127 to -128)
That's it. You can't make an iBeacon send any more data than that. It doesn't matter if the device acting as an iBeacon is your phone, an iPad, a Mac computer, or a small battery-powered unit.
If you want to tie other data to an iBeacon, you have to do it through another channel, by some kind of lookup that matches the data up with the identifiers above. You can do this with a static lookup table in your app, a web service, or a CoreBluetooth communication channel. But you have to code that yourself.
I am trying to detect if my iPhone is in the same network as my Raspberry Pi. I would like to execute a script when I am at home and my iPhone's presence is registered in my LAN.
It seems that when the phone is in standby not even the iphone-sync port (6207/tcp) is found. "/usr/bin/nmap -n -sT -p62078 [my phone's local IP]" shows no host. I wonder what else I could scan for. Obviously the phone is online and ready to accept facetime calls (data via 3G is deactivated). Could I accomplish something with avahi which I am using on my Raspberry Pi, or are there other ways.
I've just spent a week beating on this problem so I can refrain from sending SMS home alarms to my wife when she's at work.
Pinging won't work because the iPhone won't respond to ICMP when asleep. Reading the ARP cache won't work because a sleeping iPhone will come and go (check it every 30 seconds for a few minutes).
The only way I have found to 'reliably' determine when my two iPhones are on my local (home) network is to use the PCAP dotnet library to look for any packets originating from either of the phones' MAC addresses. For example, if you run Wireshark with the capture filter
ether src <iphone-mac-address>
you will see a surprising amount of network discovery/announcement traffic from the phone. It still has quiescent states, but so far the longest interval I have seen between captured packets is around 10 minutes. You would have to wait until you have not heard from the phone for some interval (I use 15 minutes) before declaring it not-home.
With this technique you will find a phone quickly when it rejoins the home network, assuming your phone is configured for DHCP. I also use port mirroring on my main Ethernet switch to include traffic from my wireless access points.
I don't have a Raspberry Pi solution for this, because my linux expertise is very limited, but someone else may be able to help you along those lines. I have a Windows Service using the PCAP library and so far it works reliably, with the limitation of waiting 15 minutes before deciding an iPhone has left the network.
* update 2-3-2018 *
I have this detection algorithm down to about 5 minutes, using a combination of ping/arp messages directed to each phone, about once per minute. Seems to work great.
You can find a list of devices on your network by investigating your arp cache.
arp -a
Simply write a bash script to run arp -a at a regular interval, and search for the mac address of your phone.
You could go even further with this and perform different actions depending on what brand of device is connected.
The first 3 hexadecimal digits of a mac address are the vendor id.
Take the following mac address:
00:19:E3:AB:CD:EF
00:19:E3: is one of the registered mac address for apple devices.
By comparing the devices on your network with this list, you could detect when for example a '3com' device, or a 'dell' device attaches to your network.
http://www.coffer.com/mac_find/?string=apple
You can do "arp-scan -l -r10" for that (tested this myself), but the problem is if mobile data enabled the iphone will go and suspend wifi if screen is locked to safe battery. so you need to disable mobile data .. then arp-scan will work.
I read a lot about Bluetooth LE in the past hours, but I do not really understand how profiles work. I want to pair an iPhone with a self-made device over BTLE.
The device should send measured temperature values, humidity or other values over Bluetooth and the iPhone should read that data.
I read about different profiles in the BTLE specs (even about heart measurement), but how does one proceed, when reading CO-emission for example?
Thanks a lot!
Regards, mary
There are two sides to this: the profile you'll define on your device and the code you'll write to communicate with this profile in your iOS application.
On the device, you'll define a profile with specific services for the measurements you want to gather. There are several standard Bluetooth LE profiles which you can find in a list on the main Bluetooth developer site. These include profiles for temperature, heart rate, and walking cadence, among others, so if you are providing measurements in one of these categories you can make your device provide one of those services and it will be usable with any iOS application that reads from that service.
For values that aren't covered by one of the existing services, such as the humidity readings you mention, you'll need to create your own custom service. You'll just have to define the service characteristics (what type of data you'll provide and how you'll provide it) and give this service a unique identifier, because it's one you're creating and not part of the standard ones laid out by the Bluetooth organization.
How you define these services and characteristics will depend on the specific Bluetooth LE hardware you use for your device. I've done most of my work recently on Bluegiga's BLE112 chip, which combines a low-power microcontroller with a Bluetooth LE transmitter. They have very good tools for defining device profiles and creating matching firmware, and it's reasonably straightforward to set this up on their chips. I can't speak for other manufacturers, but they most likely have something similar.
Once you have a profile defined on your hardware, you'll need to look for devices advertising it and be able to connect to them within your iOS application. You'll use Core Bluetooth for this, and I highly recommend starting with one of Apple's sample applications, such as their Temperature Sensor example. That example uses the standard health thermometer profile, but you can tweak it to find your proprietary services in addition to the temperature readings. You can see how they read and process the binary data returned from the LE device in that example.
I highly recommend watching Apple's two WWDC 2012 session videos on the topic, Session 703 - Core Bluetooth 101 and Session 705 - Advanced Core Bluetooth, because they provide a lot of background on the topic and show practical examples of this in use.
If I am writing my own networking services via Bonjour (instead of GameKit's implementation), is there any limit to the amount of devices that can connect to a single socket? Meaning, I have one device that is the "host", is there a limit to how many other devices can connect to the host via Bluetooth/Wi-fi?
The maximum number of remote users able to connect to the given host is dictated by the max number of file descriptors iOS allows you to open on a socket. It's not strictly a Bonjour issue. I'm unable to find any documentation for iOS but the default value for OS X is presently around 256 open descriptors per socket (low compared to other UNIXes, although it can easily be bumped).
Given the hardware constraints of an iOS device I would assume this max value is lower, but should still be in the hundreds, comfortably enough for gameplay between users on the same link-local network.
Get above that number of concurrent players and the likelihood is that CPU and network conditions would be the limiting factor anyway.
Does anyone know what kind of range can you get from the iPhone
bluetooth? Also, would the connection be strictly one to one? I know you
can choose from a number of peers to connect to but once the connection
is established, it seems you can only transfer data between one peer? So
basically, is it possible to create some kind of "multiplayer" experience?
Just answering the range part of your question...
The 10 meter figure for class 2 devices (of which the iPhone is an example) is very much a guideline.
The range of a Bluetooth device is limited by many real world factors. The 2.4 GHz radio frequency used by Bluetooth is strongly absorbed by water. For example, consider an iPhone connected to a Bluetooth mono headset. If the headset is in one ear and the iPhone is in your trouser pocket on the opposite side of your body, then there's a lot of water between the two devices. This will often cause a significant amount of packet loss in practice (you can hear this in the audio being carried). So, in this case, the range is about one meter.
At the opposite extreme, two class 2 devices separated by nothing more than clear air can get ranges of hundreds of meters.
Other factors that influence things are:
Interference - Lots of things use 2.4 GHz. WiFi, for example can cause problems.
Antenna design - Space and cost constraints often mean that the antenna design is sub-optimal. I don't know how good the iPhone is in this respect.
Walls - Generally walls attenuate Bluetooth signals. However, sometimes they are useful reflectors.
Quality of hardware - Some chips work better than others. Even different firmware revisions of the same chip may perform differently. Different versions of the iPhone probably have (or will have) different chips in them.
Protocol - It is possible to work around poor signal quality with error correction and retransmission. Even if the iPhone SDK forces you to use a particular protocol, careful design of your application can make a difference.
So, in summary, you should probably do some real world tests.
The connection is one-to-one, but you can create an adhoc network with one of the phones acting as the master/coordinator. The other phones would route all their communication through the master/coordinator.
One device can theoretically connect to 7 devices. according to the master-slave role, the device can multiplex between each of them giving the user an impression that you are connected to all of them simultaneously. Bluetooth specification does not stop you from doing that.This is theory.
Now for the iphone, whether it can connect to to more than one device can only be answered by apple or someone who knows the iphone bluetooth API. But I am pretty sure the bluetooth chip inside iphone should be able to connect to more than one device.
Range is essentially going to be good enough for a normal sized room to be covered. It can be longer or shorter depending on environmental circumstances, but remember that bluetooth was created to implement short range connections.
A bluetooth device can be part of a piconet of eight devices, one master and up to seven slaves. The slaves cannot communicate with each other, they must talk through the master, think of a star topology with the master in the center. The iPhone SDK has a GameKit framework that can be used to create the network for multiplayer games. Go to developer.apple.com at look at the GKTank and GKRocket sample code to see how it's used. These games only support two players, but the GameKit framework supports more. Look at the app store and you will see games that have four or more players.
Hope this helps to get started.
Apple iPhone 3G has a Class 2 bluetooth module. Class 2 Bluetooth devices have a communication range of 10 meters.
At a given instance a device can connect to just one device because it follows a master/slave communication model. But still we can perform a multiplexing. So we can virtually connect to more than 1 device and by rapidly changing the connected device.
I found a good article here. It explains bluetooth very well.
According to the my knowledge, multicasting is not impossible with bluetooth. So gaining a multiplayer experience is NOT impossible.
The bluetooth in the iPhone is Class-2, with a 10-meter range, approximately.
Unfortunately I can't answer the other parts of your question.
One device can be connected up to 8 others. It all depends on the iPhone bluetooth API (which I don't know anything about), but with Bluetooth itself you could then send data to multiple devices.
I tether my iPhone to my laptop over bluetooth every day, and I seem to remember having done that at the same time as using a bluetooth headset. YMMV.
It’s the latest incarnation of Bluetooth, the wireless device-to-device technology that allows your phone to talk to headsets, car stereos, keyboards and other devices directly, without the need for a router or shared wireless network.