Help with Internet connections

My idea is to buy a usb air card and plug it into my desktop along with the cat5 network cable which provides network and Internet service from the company. When I want to get on the web for personal use I'll switch to the air card, and when I want to access the network or Internet for office use I'll use the network connection. Can this be done? How do I set it up in windows 7? I'm a novice so please be as explicit and complete as possible. Thank you very much for your time and consideration.


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Depending on the software provider for the air card, you may find yourself needing to complete an authentication protocol by inputting login credentials into a third-party software application. The software application is usually provided by the 3G (or now, more commonly 4G) provider. If the air card is simply integrated into Windows, with authentication based strictly on the device's registration with the provider, you will have a more precarious situation in prioritizing network resources the way you want.

In most circumstances, you can simply unplug the air card when you do not want to use it. Therefore, you will simply be using the Cat5 network. This is the most common way of utilizing the portability inherent to removable network devices. When you do not want to use the on-board local area connection, you can simply disable it in Windows.

You can disable network adapters in Windows by going to Start -> Search -> View Network Connections

Usually, your CAT5-based ethernet connection can be disabled and enabled as the "Local Area Network" network interface card. This will be unique based on your hardware, but is commonly found to be a on-board Realtek or Intel NIC.

This is one way to segment the use of both devices without using overtly complex methods. Simply enabling and disabling the devices, or removing their physical connections, will allow you to separate and prioritize their use quickly and efficiently.

When two network interface cards are configured in Windows, irregardless of if they are WiFi, 3G/4G Air, or Wired connections, the default behavior is for Windows to attempt to use the connection which responds the fastest. However, this can be offset by a number of factors including the time it takes for the connection to reach certain domain name servers. It is possible to prioritize the use of multiple network interface cards using the manual "Interface metric" setting under Advanced TCP/IP settings for the individual adapters and using multiple default gateways. This may involve using a router whereas you can segment traffic and provide multiple default gateways. This requires extensive configuration, may not be compatible with the air card at all because the hardware may bypass your router altogether, and is an overly complex solution unless you are doing this in an environment with hundreds of users swapping around hardware.

My suggestion would be to simply disable whichever connection you do not want to use at the time. Again, the best way to do this in Window 7 is simply to disable the Local Area Connection (wired NIC) in Network Adapters. Thus, you will not need to physically disconnect the Cat5, but can prevent its use while the Air card is online.

If this suggestion does not work for you, please let me know.

Thank you for the input. I guess the most common type of situation is where I'll need an Internet connection through the air card and network access through the cat5 cable to access company files and folders. I get what you were saying about disabling the network connection but that would cut my ties to the network folders too right. Is there a way to keep access to the files and just severe the Internet connection? If there is, would my company be able to see me using the air card.


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Now we are talking about firewalling using a whitelist or a blacklist of ports.

You can not use MAC Address Filtering or even router-level filtering because Windows will not recognize the fact that certain ports are under firewall and will timeout. You need to add a firewall rule to Windows Firewall with Advanced Security. This would be an inbound and outbound rule either:

Blocking all ports EXCEPT the ones related to the Windows network for the Local Area Connection.
Blocking port 80 on the Local Area Connection (This is the port used for WWW/HTTP traffic).

Network Ports Used by Key Microsoft Server Products

This becomes a complicated endeavor. The other option:

If possible, separate the networks between "Public and Private" and create custom rules for each group. The company LAN could go into the public group, whereas you could potentially only allow Windows network traffic and NO inbound/outbound traffic outside a IP range of your corporate network. You will need to identify this IP range. If its local for your home network its likely

You can try to firewall the Local Area Connection (Wired NIC/Cat5) from accessing the Internet by creating these custom rules (or something extremely similar) by reconfiguring the Windows Firewall. Place each connection into the private or public category depending on the settings you create. This is difficult to articulate without complete knowledge of how your network is set up both on the Air card and the company network you are describing. However, reading up more on Windows Firewall and the ability to use connection profiles would be an excellent way to accomplish this task.

I hope that someone else can jump in and provide you with some additional information on this subject.

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Windows Forum Admin
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Start -> Search -> View Network Connections you can edit the Local Area Connection (Cat5/Wired NIC) and try to change the DNS servers to in order to remove the ability for you to resolve hostnames through that connection. You would want to maintain the default gateway so that you do not lose access to the Windows workgroup or Windows domain completely. This may cause a problem with Windows networking in general, but if you absolutely must cut off your own ability to access the public Internet this is one way to do it. Simply place and as the DNS servers for the wired connection. You may still be able to get by without defined DNS servers and access Windows network shares if the default gateway is maintained. However, there are no promises using this method. It is a lot easier than creating entire public/private profiles for Windows Firewall, however.

Hmmmm. I must admit I'm barely hanging onto what you are saying. Knowing what I want to do, is there one approach which is easier to put into place and more user friendly in terms of switching back and forth. If you need to know more about my work computer or it's setup I can try to provide that for you, just tell me exactly what you need and where to find it.

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