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57

3G uses CDMA (Code Division Multiple Access). On CDMA several transmitters can send information simultaneously over a single communication channel. The users share a band of frequencies employing spread-spectrum technology and a special coding scheme where each transmitter is assigned a code. Suppose a room in which people wish to talk to each other ...


41

Why doesn't mobile broadband have interference problems? It does suffer from interference, but it is mitigated so it doesn't become a problem in the common case. Why does it work? Because semi-modern cell phone systems are often built to use variations of TDMA (Time Division Multiple Access) or CDMA (Code Divison Multiple Access). The purpose of ...


17

You need to change the metric of the routes for the adapter. If you do 'route print' at a command prompt you should see the metrics for the various routes for your adapters. The route with the lowest metric will get used first when sending out traffic. If you go into the networking control panel and into the TCP/IP settings for your wifi adapter and then to ...


13

There are two kinds of radio interference: inter-cell (between cells) and intra-cell (between users in the same cell.) Mobile broadband operates on licensed frequencies, which are assigned on an exclusive basis to a single licensee for a given frequency in a given geographical area. This is in contrast to WiFi, which operates on unlicensed frequencies. So ...


7

Yes, the three main options are: Satellite internet: good bandwidth, but usually needs a separate uplink, needs a dish, usually fairly expensive 3G / UMTS: Would work, but if you're remote, chances are you don't have 3G coverage.. worth a test though WiFi with a range extender. You can stretch WiFi for a few km with the right hardware... in case a ...


6

According to airplane security regulations, you are not allowed to use cellular connections on an airplane. As far as I know, it is technically possible to make phone calls (via the 2G network). 3G has lower range, so it could be impossible to connect from that altitude.


6

Yes you can. Go to Network and Sharing Center and click Manage network connections, Right click on the 3g connection and go to properties and on the advanced tab, choose Share This Connection and choose the wireless card. Next, to set up the ad-hoc connection: Simply go to Network and Sharing Center and click on Set up a connection or Network Next, ...


6

Yes, if you have 3G coverage you can buy a 3G router and it will act as any normal WiFi router (for example with cable access). All the clients will have internet access over 3G. My advise would be: If your friend's phone is running Android 2.2 or higher, it has a built-in WiFi hotspot function. Try using this Android hotspot function and see if you can get ...


6

Why doesn't mobile broadband have interference problems? It does and most of the effort going into improving mobile broadband goes into reducing interference specifically. As a user, it is not so easy to recognize the interference problem, because your phone and the network do such a good job in hiding it. Try watching a YouTube video on your smartphone ...


6

In addition to the points about multiple channel access, TDMA and CDMA, remember that internet access is a packet-switched system. Mobile broadband relies on most connections being idle most of the time, but periodically each mobile device will request to send some data, or the base station will recieve some data for a particular base station. The channel ...


5

Since your router is reporting an IP different to your public IP, it's likely that your 3G network provider isn't allocating you a public IP and is instead performing NAT, which would also explain why port forwarding isn't working. This is confirmed if a.b.c.d is in a private IP address range: From 10.0.0.0 to 10.255.255.255. From 172.16.0.0 to ...


5

TCP and HTTP are different things. TCP is the transport layer. By definition, it's responsible for carrying application layer protocols (HTTP in your case) over it. TCP does not run over a port. It is the arbitrator of ports. In other words, when you connect to an HTTP server, you connect on TCP port 80. When you connect to HTTPS, you're connecting ...


5

If I understand your question correctly, I might rephrase it as, "If the network infrastructure allows HTTP traffic to pass on a certain port, will it also allow pure TCP (without full HTTP-compliant operation or even fake HTTP headers) to pass on that port?" Unfortunately, the answer is, "It depends on details you have not yet discovered regarding how the ...


5

Problem solved: Tested with another file type (.zip) on graphic-pc.com. Guess what, at the same time it's fast for this file and slow for the other one (which btw is .mp3). So that's clearly the ISP doing deep packet inspection and throttling. As for the strange results under windows, i tested again today and now it's exactly the same as linux. Also, the ...


5

No you can't, not via 3G, and if you did it would probably be illegal as the frequency bands used for 3G are most likely licensed to Telco's, and not for personal use. However, if your cellphone supports wifi, then you can set up an ad-hoc connection with it and the computer. If your phone can't do ad-hoc mode, then you can install software such as ...


5

You cannot "increase" the speed of the 3G connection that you have to more than what the service provider has installed or provided for. However, you can do the following to make use of as much of connectivity is available. Whatever you are using (USB dongle, direct modem, etc.) - attach an antenna to it. By far, this is your best bet. Try to get away from ...


5

In Windows Vista: Open Network and Sharing Center Manage network connections Alt-N S (Advanced -> Advanced Settings) You can change the provider order in here, however I am not sure if it affects routing to be honest. The other option would be to bridge the two connections, but then you don't have control of which connection is being used. I did this ...


4

You can't do this, you can't just replicate a 3G signal. The 3G signal is encrypted with a routing encryption and decrypted by your phone. Besides it being non-existant for consumers, your provider uses broadcasting frequencies that are restricted for other devices so even if such a device would be made, it would be illegal. Doesn't your phone have Wi-Fi ...


4

NO and it depends on request* . *This Features and specifications are subject to change without prior notification. Reference


4

Apart from the fact that you need to get your map data somewhere (i.e. over a 3G or WiFi data connection), the current answers miss the most important point: To obtain your precise location. GPS is very precise once it acquires lock on enough satellites. However, more often than not, this takes a while, especially with small receivers or in a city (where ...


4

A printer with internet printing (such as HP eprint printers) and a 3g router might work and would let the office just send a print job. Or a printer that supports airprint can be printed to from the ipad. You may need a portable wifi router in the truck for them to both connect to.


4

You could, but it will not be as straightforward as it seems. Each USB dongles creates its own network, and it will have its own external IP address. You would then need to route calls to one interface or to the other, according to some rules, which you would need to create. For simple cases, it could be OK: you could route everything that goes to your ...


4

If your dongle is behind a NAT, then it doesn't have a public IP address and your post title is misleading. Also keep in mind that an IP can be reachable, but not ping-able, if the network's gateway forbids ICMP packets. First of all, I think you should do what @Tyler suggested in a comment: contact your provider and ask them about: Can they enable public ...


3

In situations like this I usually use static routing towards the company sites, and use the alternative connection as default gateway. Was a while since I did this on Windows so my apologies if the syntax is not 100% correct. List your current routes, just for reference. print route Syntax for add a new static route, gateway is the key here. Use the ...


3

Hyper-V does not accept wireless adapters, and this "by design". To force Hyper-V to accept a wireless network adapter, one must use the old trick of camouflaging it as a dummy but acceptable virtual adapter which is bridged to the dongle adapter. Below is described how to bridge your dongle network adapter with a virtual network adapter on the host ...


3

As the GSM operator assigned you the public IP you should ensure that you enabled the firewall on your connection. In linux the firewall is based on netfilter(iptables). Most distributions have GUI to set it up. However, if you miss it you can set the minimal set of rules manually: $ iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT $ ...


3

3G does include encryption, however, it has been broken and cannot be assumed to be secure. If you are handling sensitive data on any wireless link, you should always encrypt. For many jobs the HTTPS encryption available in web browsers is sufficient. So if you wanted to read your personal emails via a web browser, that is all you need. Similarly, if using ...


3

Assuming that this issue is because windows prefers the WiFi interface over the 3G Interface, then you might need to manually raise the metric of the WiFi interface, so that Windows will not prefer it as the default interface for internet access. Check : How to select default network interface for internet? Check windows site : ...


3

There are other forms of "interference" too, including environmental and atmospheric conditions. A notable problem in the digital communications world, but little known outside it, is that of so-called multipath fading, whereby the radio signal reaching an antenna is reflected off everything around it (buildings, mountains, etc) and becomes a complete mess ...



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