Hi everybody,
I'm in the process of building an app, that will either be a live wallpaper or a real monitoring app.
Is there a way to do the equivalent of a tcpdump on a android device regarding all gsm operations, requests etc..
when you switch Node B, when you update your location the HLR, the UTRAN communication, when you call someone all the requests and acks sent, etc.
First, there must be something already made for this, if not is there a way to get these things?
Thanks!
P.S. I'm no pro with cellular network, but as a IT engineer student I got 4 hours on cellular networks, from 1G to 3G and 4G networks. And I would love to see this info, and I'm not the only one for sure
Related
Hi, anyone tried connecting to 3G in a non 3G coverage area and the connection automatically switch itself to GPRS instead of EDGE, even if EDGE is available in that area? I wanted to connect my device to EDGE if 3G is not available and not to GPRS. Pls advice... Cheers!
Hey,
The way mobile networks and handsets work is the phone will always choose the highest available connection speed possible and the network based on capacity and available resource will assign the mobile what it can. That's why a phone will always look for a 3G network before a GSM one. When the phone initiates a packet connection to the network it includes a message which tells the network it's capability such as EDGE supported, what class of GPRS capability (4 slots down / 2 up etc...) and then the network based on this message assigns the phone a resource. Most networks nowadays have enough resource to give you a fairly good connection. For example if you support EDGE you will be given EDGE assignment (8QPSK instead of 4GMSK) as the ways the data is scheduled in the network is no different between GPRS and EDGE only the connection between the handset and network is faster.
What actually happens when you change from 3G to GPRS/EDGE is you drop the connection in 3G (move out of coverage) and based on the neighbouring channel list you received off the 3G cell you look for the most suitable GSM cell. Now this cell may or may not support EDGE but in either case the handset will PRACH on the cell, the cell with then ask the handset to authenticate and in this message you send your handset capability and also information about the last RNC/PCU (in this case the one connected to the 3G cell) you were on. The new PCU then signals with your old one and re-routes the data in the backbone of the network to you on your new cell. There will be data loss but the higher layers (application) should ask for re-tries for the missing data if it's TCP data.
In summary your connection priority (if the network supports all these technologies) is: HSDPA > UMTS (3G) > EDGE > GPRS > HSCSD > CSD
Hopefully this answers you question and adds a bit of extra info...
EDIT:
P.S. Not many networks support EDGE at present but most have plans to support it in the next 12-24 months.
Gav
How do you know you are on GPRS and not EDGE??
Hi Eeter,
I don't think there is any indication on the device You could tell my doing a speed test. If you are on a GSM network where you know EDGE is used then more than likely you will be using it instead of GPRS.
Gav.
There is an easy way:
1. Install the fieldtest utility
2. Go into a data session ( streaming radio ....BBC or others )
3. Check the Fiedtest EGPRS page and look for the downling coding
4. If it shows a CS1 or CS2 it is GPRS. If it shows MCS5 etc.. It is EDGE
Checking speed only is misleading. EDGE can be slow sometimes and the speed depends not only on the air interface but on the core internet side too
Hi eeter,
Yeah I agree that a speed test could be miss-leading.
Checking if you are using a MCS instead of CS will say for sure you have an EGPRS connection.
Gav.
(Argh unable fix the topic typo... sorry)
I have some specific problem i am unable to resolve.
My phone network provider is currently still building a network (base stations) so its signal is not reachable everywhere. This is the reason they have a "roaming" contract with some other provider that has 100% coverage for my country.
The difference between them is in price of UMTS (my provider is like 2 times cheaper). I have set the priority of phone network within windows mobile 6.1 but when the connection is lost for my provider it switches to the "roaming" but never switches back when the network of my provider is available.
Does someone knows how could i resolve this issue? I have coding expirience (16 years of c/c++ of windows development) but i dont know where to start.
Can someone point me to some apis/whatever that would enable me to track who the current provider is and check what are the available providers and finally how to change provider to my original one. Basically i want to write a service that would track the current provider and if changed from my provider scan for its network periodically and change it back when needed although there are some more questions that i am at this time unable to answer (battery consumption etc, i hope the scanning for providers is a passive operation as i dont want to glow in the dark etc.).
Thank you for reading and even more for answering
Hi all-
Can someone on Rogers in Canada please corroborate this info for me?
http://forum.xda-developers.com/showthread.php?p=40906041#post40906041
Basically, it appears that LTE users who want to use wifi hotspot tethering have been kneecapped deliberately by the network; Rogers blocks tethered device traffic on the standard LTEmobile.apn. (except DNS calls, strangely) They tell me to switch to LTEInternet.apn if I want to use wifi tethering.
But when I ask technical support about this, the "LTE APN" they tell me is required doesn't appear to be LTE in anything except name. Two APNs side by side 2 minutes apart in the same physical location give network speeds 8-10x different, and my cellular monitor app shows them negotiating different connections - HSPA+ for one, LTE for the other- that can't just be congestion.
Is this just poor service in my area (seems unlikely) or is this a deliberate crippling of tethered devices by Rogers? I have a 6Gb data plan, and they're telling me I can't use it however I want, at speeds my phone is capable of running!
Hi guys
My n9005 has been having mobile connectivity issues for a while now. I'm not very knowledgeable about mobile networking and standards so I need some help diagnosing the problem before I either find a setting to alleviate the troubles or get some hardware replaced. For your reference i think has been caused by dropping my phone quite a few times so there is likely a hardware issue, i just want to better understand it to see if theres a workaround before i go spending money!
My phone works flawlessly when it displays its connect to 4G or H+ networks. However when it drops to 3G it usually does not send or receive any texts, calls, and I have no data connection.
I have fiddled around in the service menus and tried setting the band preferences to GWL, WCDMA & GSM, LTE Only, etc etc, with not much luck either having no connection or having the same issue. For reference I don't have 4G coverage at my home only H+, but when I was on holiday in the middle of no where at the National Park (I live in New Zealand) I had 4G connections the entire time with no dropping.
Now I have no idea what mobile networks use what standards/protocols so if you could recommend a setting change or identify what I should get replaced that would be great!
Cheers
Hey, guys. I'm new here, and definitely a noob.
Just a quick backstory, I live in a rural area with only satellite internet connection, aside from using my phone as a mobile hotspot. I do quite a bit of gaming when I'm at a place with low latency internet, and have recently started using my mobile hotspot for gaming (laugh all you want, it works out fine for the most part). Unfortunately, living in a rural area, there is very limited service. I'm not completely informed on the lingo, but out here, I've learned that I can only connect to two towers (?). One is HSPA+, and one is 4G LTE. Obviously, only the 4G LTE one is good for low latency connections. I know that carriers have certain towers that they try to connect to before others because the others can cost them more. My phone usually defaults to the HSPA+ network.
I have found a way to force it to the LTE signal. By going into the hidden menu > Field Test > Modem Settings > PDP Setting > APN Setting > ATTNextgenphone > Bearer - LTE, and then saving. Usually, after about 20 seconds, it will switch to LTE service. Recently, though, my phone will attempt to not use that access point, and then remain with no 4G or 4G LTE icon next to the signal strength graphic, and I cannot connect to the internet in any fashion. I'm not sure if AT&T has figured out what I'm doing (I doubt it), but I just want to know if there is any way to combat this or to go about connecting to that 4G LTE access point in an easier way? Maybe there is some sort of root (?) I can do?
Any help would be appreciated.
* (?) <-- meaning I'm not sure if I'm using the correct wording or phrasing.