[Q] 3G/4G Communication - Java for Android App Development

Hi,
I'm creating an application which contains chat and I've decided to make the communcation with sockets.
I've tested it via 2 devices in the same wifi network and it worked (Guess because they didnt pass through the gateway)..
But whenever one of the devices is using 3g/4g the socket just doing nothing and time-out.
I guess it's either the Internet company block the specific port or the company doesnt supply the public IP.
My questions are:
1) I'm using the IP address which appear in Settings->About phone->Status->IP Address, I'm pretty sure its the public address, Isn't it?
2) If it isnt, When I send request from my device to a PHP page, and take the parameter '$_REQUEST["REMOTE_ADDR"]' , I'm getting diffrent IP from the one in the device's status. It might be it?
3) Are there any familier-common ports that most company allow in 3G/4G and are good for communication between sockets?
4) If I'm screwed with this approach, can anyone recommand me a diffrent approach to implement chat except using WebService and Receiving data every few seconds which will make my DB server crash if there are more than 10 users active.
Thanks for whoever helps.
edit:
Well, I found out a way I can acheive my device's public IP programmatically.
Still have no idea how to find out programmatically which ports the device's 3G internet company blocks.
I'm thinking about just going GCM and that's it.. but I really dont want to. :\

Av1vz said:
1) I'm using the IP address which appear in Settings->About phone->Status->IP Address, I'm pretty sure its the public address, Isn't it?)
Click to expand...
Click to collapse
I'm pretty sure it isn't. Mine shows my local IP.
If it's one of these, it's just the local one:
10.0.0.0 - 10.255.255.255
172.16.0.0 - 172.31.255.255
192.168.0.0 - 192.168.255.255
(Source: http://en.wikipedia.org/wiki/Private_network#Private_IPv4_address_spaces)
I guess that you will need a public server but I'm not sure about it.

I am having a similar problem, when I call connect() on the sockets, the app blocks on 3G/4G, but works ok in Wifi connection.
What could cause this, any necessary extra initialization needed?

Well, I found out a way I can acheive my device's public IP programmatically.
Still have no idea how to find out programmatically which ports the device's 3G internet company blocks.
I'm thinking about just going GCM and that's it.. but I really dont want to. :\

Related

wifi identities

hello xda,
my wife has a htc hd2 phone from T-mobile. She turned off the 3g and
i gave her a static ip so she could connect to our wifi router at home.
so far so good. now she wants to connect to the wifi at her work,
she could just change the settings manually, but that is kind of bothersome
everytime. i guess what she needs is a procedure to setup 2 different profiles
or identities for her wifi connections--one HOME-one WORK. i have been
googling for some time, the toggle apps available seem not to fit her needs.
any advice?
thanks
craig
why have you not turned on the hdcp in your router at home and let it give her an ip dymanic ?
what??
hello,
i need a static ip becasue i host websites off a server and it was advised
many years ago that i establish a static ip's for all my machines in the house.
any help?
zpupster
You should be able to have certain things static in your house, while using a specific range that doesn't interfere with your other devices as dynamic...at least that's how my setup works.
gsvnet said:
You should be able to have certain things static in your house, while using a specific range that doesn't interfere with your other devices as dynamic...at least that's how my setup works.
Click to expand...
Click to collapse
I think this best answers your problem.
There are cases that you need a static and a dynamic setup in your house.
And I think by doing that, there will be less problem with regards to changing the settings of your wife's phone connection.
_____________________
yeah having a computer with a static ip don't interfere with the rest of the devices using the dhcp

[Q] Any solution to keep IP from changing?

I know that this thread will probably be over in approximately 3 posts, but I figured this was the place to ask to get a good answer.
I am part of staff for a site that uses my IP to enable staff functions. These functions are set to the IP I'm on. However, it never works considering my IP constantly changes when I'm on the T-Mobile network, and I do not have access to wifi. Is there any possible way at all, to be able to make this work, either from my N1, or on my PC using my N1 as a 3G hotspot? I'm not all that knowledgeable about networking, but I'm thinking there has to be some possible way to make this work somehow. Maybe I'm wrong and it is one of the impossible things to do on a cell network.
Thanks for any help.
how often does it change ? is the running at home or the pc u are tethering with it ? are you using a 3g network service for a server
Every couple minutes at least. One minute it's for example, something like 208.54.27.50 and in a matter of 5 minutes the last two digits could be changed. I use the 3G hotspot at home and there's no difference from that and using the phone's browser itself. I do not use T-Mobile 3G to operate any servers.
If it is via your provider you have no control over it changing as they assign you a dynamic IP. If you were at home you could set it to a static local IP (Over WiFi) but outside your LAN on T-Mobile's WAN you have no control over DHCP
All I use for internet access on the go and at home is the 3G hotspot that I get from my phone. Would I need an actual Wifi connection from an ISP other than T-Mobile to set it to a static local IP?
looks like that just cant be done.. either ur site changes ur auth to id pw based one(atleast in ur case)
or ..
if its a job of just checking somthing, u can find a friend or family member with a 24/7 online pc(with a a static ip) and just do the job thru a remote desktop connection
All right guys. Thanks. Very much appreciate your thoughts and for not flaming me due to an obvious answer. Thank you again.

[Q] Trace routes using your hd2 andriod

I Have been doing some looking and testing of my device in regards to network routes.
I have used several tools both on the hd2 and tethered with some very crouis results.
The list is as follows
Trace route android hd2 using tmobile usa
Can someone tell me if the device has be targeted by virus or worm
n
10.168.189.10 (10.189.168.10.in-addr.arpa)
9.189.168.10.in-addr.arpa
21.189.168.10.in-addr.arpa
67.189.168.10.in.addr.arpa
49.189.168.10.in-addr.arpa
173.135.164.10.in-addr.arpa
149.135.164.10.in-addr.arpa
25.189.168.10.in-addr.arpa
36.189.168.10-in-addr.arpa
Post your routes and let's compare
If you are a dev and find this can help let me know I may be able to provide more information.
i dont understand what you mean or how did you test. Can you explain please.
Usually if you are tracing, you need a source IP address and a target IP address. It can be a specific single ip address or an ip network. So how do you test this, do you use a router and connect to it via wifi or do you use data connection? Or are these IPs you provided the targeted ones?
whys this in the dev section? this should be in the Q&A section
This makes no sense. A traceroute is a command that will tell you all the hops it takes to get from point a to point b, and the latency timing between them. That will in no way tell you if you have a virus or not. If you went into a command prompt on windows, for example, and typed tracert www.google.com it would show you the route it took to get there. This route can be different depending on when it's run.
Now, if you're really worried, and you have an ip that's been connecting to you, and you're unsure of it, a good place to start would be running an nslookup or a whois and seeing who it's registered to.
Even then, however, I still have no idea what it is your even asking. Perhaps a little more info? (And like others have said, wrong section.) Perhaps if you even told us what tools you used, and what your were looking for...
Ok I used several (targets) google.com, yahoo.com, IBM.com and so on.
Ok this is not the total list of the trace log only the ip and servers i don't understand or can't explain.
I used both my hd2 as the source and as a pass-thru as a hotspot.
The trace route command tracks the path to the target. As you can see from my data the traffic I'd several address not even listed in the US but in the UK. I am wondering why the phone might doing this as in a worm, virus, ghost program?
/sigh
Again, this is not what the traceroute command is used for. It's used when you can't hit a certain address, and you want to find out where the signal is getting lost/stopping. Traceroute has nothing to do with viruses, or virus detection. You just don't seem to understand how internet routing works.
Seems like it's time for you to google networking, tcp/ip, ip4, traceroute, etc... start reading about this stuff. In the interest of saving time, however, what you're doing is like me bringing my car in for service worrying that something is wrong with it mechanically because the gps is telling me to turn on the wrong street.
?
Maybe i am confused?
Maybe I don't know what i am talking about you try it and post what you get please.
Try out the app Landroid from the market and post what your routes are.

Internet issues with Android devices at school

Hi,
Just got a shiny new Galaxy Note 10.1 last weekend. Yesterday, after receiving my case and keyboard from Amazon, I brought it in to school to start taking advantage of the S-Pen for note taking in classes that keyboards don't quite cut it in. Unfortunately, it revived an issue that I had and ignored on my HTC Rezound from last year... an issue that a WiFi device can't ignore, and unfortunately my phone's battery is not up to using CM10's tether function all day (and it might start running down my monthly data being used 5 days a week, all day).
So, any ideas what might cause this issue? The school primarily has Macs, and my Windows 8 Laptop sometimes has issues, but at least half the time it works fine. It is just Android devices that will not work. They connect, and get great signal strength, but just won't get any actual data. To my knowledge, nobody has ever gotten an Android device to connect. My Rezound is running an unofficial CM10 (4.1 JB) version, and my Note is using whatever the newest official update is (4.1 as well, I believe. Non-rooted). I don't know a whole lot about this type of stuff, but I'm not afraid to tinker around to try and get it working. I've tried a few other suggestions from numerous Google searches, but to no avail so far. The network is unprotected, and run by the school's IT people, so needless to say I have no way to easily change settings for the campus' network. I'd prefer not root the Note just yet, but if I need to, so be it. Any ideas what this might be?
Thanks
Some more Info
Coffeeist said:
[Original Post]
Click to expand...
Click to collapse
Some more info:
I cannot ping the tablet from my laptop (I get no packet loss, but all return 'Destination Host Unreachable'.
Same result if I try pinging my laptop or the router from my tablet using Terminal Emulator.
Sometimes, if set to DHCP, the tablet will give an 'Authentication Error Occured' error (or similar, I don't recall the actual wording). Sometimes it indicates a connection, but just won't work. I've never had a problem connecting using the same info as my laptop (with the IP changed, of course), but again, no internet, no ping.
Thanks
May or may not be the problem, but from what I've noticed, school networks tend to have a lot of blocked ports. I know the main Google Sync Framework uses port 5228. Try shooting an email to a network admin in your school's IT dept, asking about that port or just in general if they're aware that Android devices are unable to connect on their network.
Coffeeist said:
Some more info:
I cannot ping the tablet from my laptop (I get no packet loss, but all return 'Destination Host Unreachable'.
Same result if I try pinging my laptop or the router from my tablet using Terminal Emulator.
Sometimes, if set to DHCP, the tablet will give an 'Authentication Error Occured' error (or similar, I don't recall the actual wording). Sometimes it indicates a connection, but just won't work. I've never had a problem connecting using the same info as my laptop (with the IP changed, of course), but again, no internet, no ping.
Thanks
Click to expand...
Click to collapse
What do you mean by "same info as my laptop" what types of credentials are you referring to? Something you have to change on the laptop in order to get in? The more information regarding this you can provide (safely, mind you, mask/alter any sensitive info), the better we can assist you. If you have to do something like set a VLAN, then you're never going to get an Android device to work as we do not have the capability to use VLAN'd wireless like most PCs and Macs can with the proper configuration changes. If there's some browser catch-all page, then that should work, but based on your statement "with the IP changed" leads me to believe that you're messing with the adapter settings directly. I would be especially keen to helping you with more detailed networking issues like this should you provide me with the information requested. I look forward to your reply. (Yes, I like technical challenges like this, it's why I work VoIP support.)
IP address or no IP address
Coffeeist said:
Some more info:
I cannot ping the tablet from my laptop (I get no packet loss, but all return 'Destination Host Unreachable'.
Same result if I try pinging my laptop or the router from my tablet using Terminal Emulator.
Sometimes, if set to DHCP, the tablet will give an 'Authentication Error Occured' error (or similar, I don't recall the actual wording). Sometimes it indicates a connection, but just won't work. I've never had a problem connecting using the same info as my laptop (with the IP changed, of course), but again, no internet, no ping.
Thanks
Click to expand...
Click to collapse
since you know ping, then did you check the IP address for each device?
Back to basic:
1: ping your device gateway IP
2) if ok, then ping ur device (tablet or laptop)
3) if ok then ping bbc.co.uk (this will check your dns), if failed ping your dns's IP address.
If no IP on android, then check if there is any protection on device. It sound like no IP been allocated for you.
Depends on how good a school's IT dept. I have not seen many school actually put filter to stop non-window device.
I am not sure it has anything to do with VLAN yet. As a simple logon, device does not care VLAN or no VLAN.
The basic for us is 1) get an IP on device. 2) know how to get out (gateway IP) 3) interrept hwere you go (DNS resolution) 4) know how to get to internet (internet router, internet firewall, internet boardband et...)
If you have authentication error, then it is sure you are not going to get an IP address. If this is WiFi then check on security (WEP, WAP...TKIP...)
tinbox134 said:
since you know ping, then did you check the IP address for each device?
Back to basic:
1: ping your device gateway IP
2) if ok, then ping ur device (tablet or laptop)
3) if ok then ping bbc.co.uk (this will check your dns), if failed ping your dns's IP address.
If no IP on android, then check if there is any protection on device. It sound like no IP been allocated for you.
Depends on how good a school's IT dept. I have not seen many school actually put filter to stop non-window device.
I am not sure it has anything to do with VLAN yet. As a simple logon, device does not care VLAN or no VLAN.
The basic for us is 1) get an IP on device. 2) know how to get out (gateway IP) 3) interrept hwere you go (DNS resolution) 4) know how to get to internet (internet router, internet firewall, internet boardband et...)
If you have authentication error, then it is sure you are not going to get an IP address. If this is WiFi then check on security (WEP, WAP...TKIP...)
Click to expand...
Click to collapse
Hello Coffeeist,
Please contact your schools IT department and find out what kind of encryption they use on their APs.
If they use TKIP, then that is whats causing the problem with android devices.
Once TKIP is disabled on the AP you are connecting to, you will be able to reach the internet.
I say this because I had the same problem in the past (setting up Cisco APs), and can confirm that this is the cause of the problem.
TKIP shouldn't be used anyway. They should be using AES. TKIP is too weak.
I guess that last part answered another question that you might of had. (Why TKIP doesn't work with Android?) Android=Secure TKIP=WEAK.... Unacceptable for Android
Also, you mention something about not being able to ping your tablet from your laptop. If I understand this correctly, you have both your laptop and tablet connected to the same AP and you are trying to ping between the two. This wont work in most cases. Reason: "Port-Protection", which if enabled doesn't allow clients on the AP to communicate with each other.
Regards,
Ed
Let us know how it goes.
nasvi said:
Hello Coffeeist,
Please contact your schools IT department and find out what kind of encryption they use on their APs.
If they use TKIP, then that is whats causing the problem with android devices.
Once TKIP is disabled on the AP you are connecting to, you will be able to reach the internet.
I say this because I had the same problem in the past (setting up Cisco APs), and can confirm that this is the cause of the problem.
TKIP shouldn't be used anyway. They should be using AES. TKIP is too weak.
I guess that last part answered another question that you might of had. (Why TKIP doesn't work with Android?) Android=Secure TKIP=WEAK.... Unacceptable for Android
Also, you mention something about not being able to ping your tablet from your laptop. If I understand this correctly, you have both your laptop and tablet connected to the same AP and you are trying to ping between the two. This wont work in most cases. Reason: "Port-Protection", which if enabled doesn't allow clients on the AP to communicate with each other.
Regards,
Ed
Let us know how it goes.
Click to expand...
Click to collapse
With useful posts above the rest is not much left for me to say but a simple advice
Make sure your friends aren't playing a prank on you coz I tend to do it I use arpspoof and aireplay-ng to cause such mayhem
Sent from my A116 using Tapatalk 2
Airplay and Arpspoof wouldn't be possible if MFP is enabled on the AP. Also the OP is stating that it is with all android devices and not 1.
Sent from my HTC One XL using xda app-developers app
responses
First off, thanks for all of the posts, and I apologize for taking so long to respond.
Also, I did check port 5228 with my laptop, and it seemed to indeed be closed. Haven't been able to contact IT yet, but I will need to soon to solve an issue with another, unrelated issue.
Cynagen said:
What do you mean by "same info as my laptop" what types of credentials are you referring to? Something you have to change on the laptop in order to get in? The more information regarding this you can provide (safely, mind you, mask/alter any sensitive info), the better we can assist you. If you have to do something like set a VLAN, then you're never going to get an Android device to work as we do not have the capability to use VLAN'd wireless like most PCs and Macs can with the proper configuration changes. If there's some browser catch-all page, then that should work, but based on your statement "with the IP changed" leads me to believe that you're messing with the adapter settings directly. I would be especially keen to helping you with more detailed networking issues like this should you provide me with the information requested. I look forward to your reply. (Yes, I like technical challenges like this, it's why I work VoIP support.)
Click to expand...
Click to collapse
Just IP/DHCP/DNS (and I've also tried public DNS such as Google). Nothing fancy set up on the laptop (everything should be on Windows default network settings, same with Android on both devices). There is also no catch-all page, assuming I'm interpreting that correctly (as a login page sort of thing, like I'd get at Starbucks or a Hotel).
Glad to provide the challenge... truth be told, underneath the annoyance of lacking connection, I love issues like this because of the fun tricks and such that solving them can teach.
tinbox134 said:
since you know ping, then did you check the IP address for each device?
Back to basic:
1: ping your device gateway IP
2) if ok, then ping ur device (tablet or laptop)
3) if ok then ping bbc.co.uk (this will check your dns), if failed ping your dns's IP address.
If no IP on android, then check if there is any protection on device. It sound like no IP been allocated for you.
Depends on how good a school's IT dept. I have not seen many school actually put filter to stop non-window device.
I am not sure it has anything to do with VLAN yet. As a simple logon, device does not care VLAN or no VLAN.
The basic for us is 1) get an IP on device. 2) know how to get out (gateway IP) 3) interrept hwere you go (DNS resolution) 4) know how to get to internet (internet router, internet firewall, internet boardband et...)
If you have authentication error, then it is sure you are not going to get an IP address. If this is WiFi then check on security (WEP, WAP...TKIP...)
Click to expand...
Click to collapse
1. If I recall, this either had full loss, or Destination Host Unreachable, when pinging the gateway IP from the tablet.
2. Have tried this nonetheless, and I think I made it through once or twice just after turning on the tablet, but after that would only get Dest. Host Unreachable.
3. Had tried with Google, fails across any DNS.
I seem to get an IP, although sometimes I get the authentication error in Android and it won't connect. Whenever I set a static IP, based off of my laptop's IP (not the same, of course), I get connected, just no internet.
nasvi said:
Hello Coffeeist,
Please contact your schools IT department and find out what kind of encryption they use on their APs.
If they use TKIP, then that is whats causing the problem with android devices.
Once TKIP is disabled on the AP you are connecting to, you will be able to reach the internet.
I say this because I had the same problem in the past (setting up Cisco APs), and can confirm that this is the cause of the problem.
TKIP shouldn't be used anyway. They should be using AES. TKIP is too weak.
I guess that last part answered another question that you might of had. (Why TKIP doesn't work with Android?) Android=Secure TKIP=WEAK.... Unacceptable for Android
Also, you mention something about not being able to ping your tablet from your laptop. If I understand this correctly, you have both your laptop and tablet connected to the same AP and you are trying to ping between the two. This wont work in most cases. Reason: "Port-Protection", which if enabled doesn't allow clients on the AP to communicate with each other.
Regards,
Ed
Let us know how it goes.
Click to expand...
Click to collapse
Unless I am totally clueless about this stuff (er, moreso than I though I already was), it uses neither TKIP or AES, being an open and unsecured network.
sak-venom1997 said:
With useful posts above the rest is not much left for me to say but a simple advice
Make sure your friends aren't playing a prank on you coz I tend to do it I use arpspoof and aireplay-ng to cause such mayhem
Sent from my A116 using Tapatalk 2
Click to expand...
Click to collapse
Haha, I doubt it. None of my friends, especially the ones who I think would even try and do something like this, are tech-savvy enough for me to have any suspicion of that. Thanks though
Another piece of info (a pretty weird seeming one at that): Sometimes, I'll turn on my tablet in the middle of the day, and out of the blue there is an email notification there, for recent emails. Of course, if I go into browser, I can't get any pages. Can't think of any other networks that the device could/would connect to on campus, either.
Thanks!
Coffeeist said:
First off, thanks for all of the posts, and I apologize for taking so long to respond.
Also, I did check port 5228 with my laptop, and it seemed to indeed be closed. Haven't been able to contact IT yet, but I will need to soon to solve an issue with another, unrelated issue.
Just IP/DHCP/DNS (and I've also tried public DNS such as Google). Nothing fancy set up on the laptop (everything should be on Windows default network settings, same with Android on both devices). There is also no catch-all page, assuming I'm interpreting that correctly (as a login page sort of thing, like I'd get at Starbucks or a Hotel).
Glad to provide the challenge... truth be told, underneath the annoyance of lacking connection, I love issues like this because of the fun tricks and such that solving them can teach.
1. If I recall, this either had full loss, or Destination Host Unreachable, when pinging the gateway IP from the tablet.
2. Have tried this nonetheless, and I think I made it through once or twice just after turning on the tablet, but after that would only get Dest. Host Unreachable.
3. Had tried with Google, fails across any DNS.
I seem to get an IP, although sometimes I get the authentication error in Android and it won't connect. Whenever I set a static IP, based off of my laptop's IP (not the same, of course), I get connected, just no internet.
Unless I am totally clueless about this stuff (er, moreso than I though I already was), it uses neither TKIP or AES, being an open and unsecured network.
Haha, I doubt it. None of my friends, especially the ones who I think would even try and do something like this, are tech-savvy enough for me to have any suspicion of that. Thanks though
Another piece of info (a pretty weird seeming one at that): Sometimes, I'll turn on my tablet in the middle of the day, and out of the blue there is an email notification there, for recent emails. Of course, if I go into browser, I can't get any pages. Can't think of any other networks that the device could/would connect to on campus, either.
Thanks!
Click to expand...
Click to collapse
Based on your responses, I have a follow up question and comment. The question is as follows: Did you have to register your computer with your IT when you started school in order to be permitted on the wireless network? If this was the case they're likely filtering based on MAC address (which you won't be able to spoof on your Android, but you may be able to spoof on your laptop), get them to re-register your laptop after you spoof the MAC address so you can get both devices on using the same MAC address (though not at the same time of course unless you're fine with stuff randomly not working). The comment is as follows: Yeah, finding the workarounds to get back limitations like this is definitely a fun challenge because when you win, you've definitely learned something new. Oh, and you were right about my question of the gateway authentication page like a hotel wifi login page.
MAC
Cynagen said:
Based on your responses, I have a follow up question and comment. The question is as follows: Did you have to register your computer with your IT when you started school in order to be permitted on the wireless network? If this was the case they're likely filtering based on MAC address (which you won't be able to spoof on your Android, but you may be able to spoof on your laptop), get them to re-register it after you spoof the MAC address so you can get both devices on using the same MAC address (though not at the same time of course). The comment is as follows: Yeah, finding the workarounds to get back limitations like this is definitely a fun challenge because when you win, you've definitely learned something new.
Click to expand...
Click to collapse
Nope, it was up and running just through connecting normally, and has been since (mostly) - no registration or anything like that. Now, the reason that I put 'mostly' in parentheses is that sometimes the computer will be connected, but also have no internet (I don't think this started until I, dare I admit, upgraded to Windows 8). However, this only happens sometimes, whereas the Android devices never get internet access.
However, on the topic of MAC addresses, one post (in fact, I think it was on XDA) I saw awhile back while Google searching this problem was that someone had a similar issue, found to be with their device's MAC address having the letters 'FA' instead of 'FB' or something like that. Being that my Note isn't rooted, I haven't tested it with that, but perhaps I should give that a try with my CM10 Rezound?
(This is the post: HERE)
Thanks!
Coffeeist said:
Nope, it was up and running just through connecting normally, and has been since (mostly) - no registration or anything like that. Now, the reason that I put 'mostly' in parentheses is that sometimes the computer will be connected, but also have no internet (I don't think this started until I, dare I admit, upgraded to Windows 8). However, this only happens sometimes, whereas the Android devices never get internet access.
However, on the topic of MAC addresses, one post (in fact, I think it was on XDA) I saw awhile back while Google searching this problem was that someone had a similar issue, found to be with their device's MAC address having the letters 'FA' instead of 'FB' or something like that. Being that my Note isn't rooted, I haven't tested it with that, but perhaps I should give that a try with my CM10 Rezound?
(This is the post: HERE)
Thanks!
Click to expand...
Click to collapse
That shouldn't be it unless they have corporate level routers that don't recognize the MAC address of any devices manufactured after 2009 (when most of these manufacturers got the MAC addresses assigned to them (this is VERY unlikely)). I would honestly work with IT on campus and advise that it appears not a single Android device is allowed on the network. If they're blocking Android for any reason, check the terms of service for using the WiFi and see if there's any provisions for banning an entire brand of device/OS for whatever reason. If there's only provisions for individual banning, then take it back to them and show them that your record has not been abusive in the least and go from there. Make a case, otherwise draw one up with legal council. *shrugs* I don't believe anyone should ever be punished for the type of device they chose to purchase, that's first amendment choice, but it really comes down to their terms of service which you agree to by using the wifi.
Cynagen said:
That shouldn't be it unless they have corporate level routers that don't recognize the MAC address of any devices manufactured after 2009 (when most of these manufacturers got the MAC addresses assigned to them (this is VERY unlikely)). I would honestly work with IT on campus and advise that it appears not a single Android device is allowed on the network. If they're blocking Android for any reason, check the terms of service for using the WiFi and see if there's any provisions for banning an entire brand of device/OS for whatever reason. If there's only provisions for individual banning, then take it back to them and show them that your record has not been abusive in the least and go from there. Make a case, otherwise draw one up with legal council. *shrugs* I don't believe anyone should ever be punished for the type of device they chose to purchase, that's first amendment choice, but it really comes down to their terms of service which you agree to by using the wifi.
Click to expand...
Click to collapse
I'll give it a shot, thanks.
Coffeeist said:
I'll give it a shot, thanks.
Click to expand...
Click to collapse
Sorry to bump the thread, but seeing as it's my own I figured it would be alright...
I got around to asking the the school IT about the issue, and they said that the deliberately block mobile traffic, which they went on to find out does include Android tablets (I understand phones, but I can't even begin to understand why they target Android tablets... unfortunately, that's not my call). I Google searched a bit, and found that networking devices from a company called Aruba can be set to block traffic from specific types of devices (supposedly Cisco and a few other companies can do similar things too), by checking something with the HTML version, or something like that (I'm by no means a networking expert hehe).
So, I guess I'll make my last effort with this thing, and ask if anyone knows of some legal, non-hacky way of getting by this?
I'm guessing not, but worth asking.
Thanks
Coffeeist said:
Sorry to bump the thread, but seeing as it's my own I figured it would be alright...
I got around to asking the the school IT about the issue, and they said that the deliberately block mobile traffic, which they went on to find out does include Android tablets (I understand phones, but I can't even begin to understand why they target Android tablets... unfortunately, that's not my call). I Google searched a bit, and found that networking devices from a company called Aruba can be set to block traffic from specific types of devices (supposedly Cisco and a few other companies can do similar things too), by checking something with the HTML version, or something like that (I'm by no means a networking expert hehe).
So, I guess I'll make my last effort with this thing, and ask if anyone knows of some legal, non-hacky way of getting by this?
I'm guessing not, but worth asking.
Thanks
Click to expand...
Click to collapse
Before discussing any workarounds, you may need to review the Terms of Service for your wifi on the school premises first, review the consequences for bypassing their security measures, and figure if it's worth the risk to you... At this time, it'll be kind of "hacky" to get around such a block. In order to provide you with a valid workaround though we'll need a little bit of information regarding what's going on when you connect.
First, when you connect to the WiFi with your Android device, do you even receive an IP address? If you don't then we'll stop here, the only way to get around the types of blocks they're employing at this level would require hardware hacking/firmware reprogramming to change the identity of the device itself, which is flat out illegal in just about anywhere I can think of. Here's your checklist, fill out where applicable: (Even if you set static information to accomplish this, that will be a valid Y.)
Get an IP? (If Y, proceed)
Is it a valid IP address on the same network as your PC? (Either way, don't care)
Can you ping the gateway you got from DHCP on Android? (If Y, proceed)
Can you ping the DNS server(s) you got from DHCP on Android? (If Y, proceed)
Can you ping an external server such as Google DNS (8.8.8.8) on Android? (If Y, then we're done here)
It's kind of a bit of a process unfortunately, however, if you pass every single one of these tests with the Android device, there's good news. They're only filtering traffic based on the User-Agent identification of all your applications (and based on the MAC address of your device, denying your DHCP requests), you should be able to bypass this with a VPN tunnel back to your home from your Android (after setting your static IP) in order to encrypt and keep this information from leaking to their systems. However, this will likely set off alarms if they monitor their network heavily. If the school IT asks, then you're "working on projects in-between classes on your computer at home and your family has a home office with VPN already, so you used that to connect back to the house". Either way, they can't say much about it besides cut you off... again. Anywhos, I wouldn't recommend trying to bypass without doing all this research first, and then also evaluating the possible consequences, however the rewards are within themselves. You'll be the only person at school with a working mobile device, (besides those iSuckers). Technically, encrypting your traffic is completely legal (and they can't say anything legally about it), however, setting a static IP address in the same range as your computer at school may be against their TOS which you abide by being on campus. Let us know how everything goes.
Cynagen said:
Get an IP? (If Y, proceed)
Is it a valid IP address on the same network as your PC? (Either way, don't care)
Can you ping the gateway you got from DHCP on Android? (If Y, proceed)
Can you ping the DNS server(s) you got from DHCP on Android? (If Y, proceed)
Can you ping an external server such as Google DNS (8.8.8.8) on Android? (If Y, then we're done here)
Click to expand...
Click to collapse
With Static I set an IP and all other info (Gateway, DNS, etc, except for Network Prefix Length... no clue what that is, left it at 24 default), and could not ping gateway
Dynamic/DHCP I will have to check tomorrow, after downloading stuff for the tablet to get that info (I think I need root to use IfConfig with Terminal Emulator, correct?).
Whatever they use to block me out, it seems to have a slight hole built in... every day, multiple times a day, I will look down at my tablet and see notifications (mainly email, occasionally Facebook, etc) that pushed through on the schools network (I know that for sure, being that often times the emails are messages received during the day, in a time period where the tablet has been nowhere near any other networks). Maybe this hole can be breached?
Thanks!
Coffeeist said:
With Static I set an IP and all other info (Gateway, DNS, etc, except for Network Prefix Length... no clue what that is, left it at 24 default), and could not ping gateway
Dynamic/DHCP I will have to check tomorrow, after downloading stuff for the tablet to get that info (I think I need root to use IfConfig with Terminal Emulator, correct?).
Whatever they use to block me out, it seems to have a slight hole built in... every day, multiple times a day, I will look down at my tablet and see notifications (mainly email, occasionally Facebook, etc) that pushed through on the schools network (I know that for sure, being that often times the emails are messages received during the day, in a time period where the tablet has been nowhere near any other networks). Maybe this hole can be breached?
Thanks!
Click to expand...
Click to collapse
It seems like small gaps where the system doesn't block you long enough to receive some traffic, but that is promising. BTW, you can get your "network prefix" (netmask as we call it) from your computer. If you go into the command prompt on windows and run "ipconfig /all" you'll get 4 useful bits of info we need, IP address (so you can mimic it), the gateway, the subnet mask (usually 255.255.something.something) and the DNS servers. The subnet mask determines what you use, and I HIGHLY doubt they use 24 (that's mainly for home networks, 24 = 254 devices permitted on the DHCP, 16 = 65534 devices (this is WAY more likely)).
Cynagen said:
It seems like small gaps where the system doesn't block you long enough to receive some traffic, but that is promising. BTW, you can get your "network prefix" (netmask as we call it) from your computer. If you go into the command prompt on windows and run "ipconfig /all" you'll get 4 useful bits of info we need, IP address (so you can mimic it), the gateway, the subnet mask (usually 255.255.something.something) and the DNS servers. The subnet mask determines what you use, and I HIGHLY doubt they use 24 (that's mainly for home networks, 24 = 254 devices permitted on the DHCP, 16 = 65534 devices (this is WAY more likely)).
Click to expand...
Click to collapse
Well, I just had a clean connection for about 5 minutes, and had a normal-looking IP based on my PC. Using Terminal Emulator I pinged the gateway after my connection failed, still with no response. I still appeared to have a proper IP on my tablet, but no actual internet connection.
So, perhaps these small windows are something to pursue? Or perhaps sticking with the VPN plan is best?
Thanks!
Coffeeist said:
Well, I just had a clean connection for about 5 minutes, and had a normal-looking IP based on my PC. Using Terminal Emulator I pinged the gateway after my connection failed, still with no response. I still appeared to have a proper IP on my tablet, but no actual internet connection.
So, perhaps these small windows are something to pursue? Or perhaps sticking with the VPN plan is best?
Thanks!
Click to expand...
Click to collapse
You need to make sure your networking information is entered correctly, you still haven't said anything about the netmask in this situation. However, if you're entering this information in correctly then you should have a solid connection until they realize you've forced a device into the network. The only thing you can do beyond that point is during that window, open a VPN connection without using a single browser request so they don't know what the device is unless they check the MAC address. Either way, this is a window that can be used, you just need to avoid identifying your device in any way prior to initiating the VPN connection. Turn off Sync when you connect.

[Q] Active FTP Connections Not Working

Hey all. I recently purchased a Verizon Samsung Galaxy S4 32GB and have really enjoyed it. Today I ran into my first issue, and boy its a doozy. Apparently I'm not able to make a solid connection to FTP servers using Active FTP. If I switch to passive, everything connects fine. When I switch to Active, it connects to the FTP server, but is not able to retrieve the directory listing (Filezilla error on laptop) and on my phone it states "425 Could not open data connection to port 48891:Connection timed out". This is replicated on my laptop (Through Mobile Hotspot) and on an ftp client on my phone. I work in IT and use my mobile hotspot as an external network when we need to rebuff a vendor's claims that our network is the issue (I'm sure those of you in IT also can appreciate the pain of having a vendor blindly blame your network instead of fixing their own problems).
Verizon claims that it does not block any ports. Samsung has stated that they do not support this issue, but I talked the supervisor into filing an engineer report (If that will even do anything) even though I won't hear back from them regarding this. So I am hoping I can get some help from the best android community out there!!!
Has anyone else tried to make an active FTP connection from a Verizon S4?
Would anyone be willing to give it a try?
UPDATE:
Well the Verizon guy did some testing for me (Kudos to VZW). They dont block ports, but they also don't forward the return connection for Active FTP. If anyone else wants to give it a try and let me know if it works for other providers, it would be appreciated. I may have to just fork out $$$ for a Public IP on our VZW Jetpack.
Remember that most carriers use CGN (Carrier-grade NAT) on their network, specially for mobile phones. While CGN is supposed to be stateful, Verizon probably has a broken implementation as it doesn't redirect a port to your private IP (something done in Linux by using the conntrack_ftp module). Anyway, using non-passive FTP is almost always a bad idea if you don't have a public IP. Sticking to passive is your better option.
I wish that was possible unfortunately the vendor is using active FTP for his application. I am testing to see if the internal network is the cause of the connection problems we've had. To get him to move over to passive since it is better

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