Just as the question says, what is the Microsoft Loopback Adapter, and as a bonus, what scenerios as a developer would it be useful? I've noticed it's been required when installing a couple of applications to my machine, but aside from guessing, I've never have had a sturdy understanding of it's functionality.
I've read a couple of articles online, but nothing really made me "get it". While I don't need a hugely complex answer, a little explaination would be very useful.
Thanks! George
When sending messages to 127.0.0.1 (or the localhost) the internal network driver typically handles this by shortcutting a few steps.
If you have a networksniffer/protocol analyzer like wireshark, it can not see these shortcutted packets.
By using a loopback adapter, the messages get send much further through the stack, enabling programs like wireshark to capture the packets (and enabling you to analyze the packets)
Well, the best answer I can give you is a few links. http://en.wikipedia.org/wiki/Loopback The key sentence here is
"Any traffic that a computer program sends to the loopback interface is immediately received on the same interface."
http://www.juniper.net/techpubs/software/erx/erx50x/swconfig-system-basics/html/system-mgmt15.html This may be a little more obscure if you don't know networking well.
Basically, it's a fake network interface, useful for tests and stability. In practice, most likely something you'll never have to worry about (or you'd already know about it!)
Some software requires some network functionality, even if the machine in question doesn't have network functionality. The loopback is a dummy network driver, which can have real network protocols bound to it. This allows the software to install properly, even though there isn't a real network card installed in the machine.
A loopback adapter is required if you are installing on a non-networked computer to connect the computer to a network after the installation.
When you install a loopback adapter, the loopback adapter assigns a local IP address for your computer. After the loopback adapter is installed, there are at least two network adapters on your computer: your own network adapter and the loopback adapter. You can change the bind order for the adapters without reinstalling the loopback adapter. The bind order of the adapters to the protocol indicates the order in which the adapters are used. When the loopback adapter is used first for the TCP/IP protocol, all programs that access TCP/IP first probe the loopback adapter. T
It is mostly used if you have programs that have an expiration date, so that it keeps working.
