do need to enter the user name and password when TCP/ip communication between two computers

[Jimmyzeng]

do we need to enter the user name and password when use TCP/IP to do the communication between two computers?

[SteveChandler]

It depends on the server. TCP/IP is just the communications protocol and doesn't know anything about authentication. The program listening on the port might require it.

The answer is no.

[Dustin_D]

I'm just going to jump in and let you know that there's not enough information to even begin answering this question.

Here's some things to consider:

TCP/IP just simply means you are either connected, over ethernet, wifi, or loopback(that's just talking to yourself without the use of a network card)  As you will see from the wikipedia article, it is a layered suite of protocols, while the layers may seem cumbersome its worth familiarizing yourself so you can describe what you are trying to do, because it is not always straightforward.

Basic network connectivity is another item that you may as well test first and post the results when you try to post intially because anyone that might answer your question is going to ask anyways. Can you do a ping command from one node to another?  If you can't you should start troubleshooting at the bottom of the OSI layers to look for your problem.

Also when you post back please include some sort of application information, or what program to what program, I suppose we could assume LabVIEW, but TCP/IP is pretty generic.  If you can also try to give a description of what you are trying to acomplish at a higher level and you don't quite understand what to do, you are almost certain to get some clarification that will prove to be helpful around here.

Cheers!

[SteveChandler]

I'm guessing he is trying to copy a file.

[Jimmyzeng]

Hi Dustin,

Thank you for your reply. I know what you are concerning. The detail as below:

I would like to make a software by Labview to read the data from another computer with user name and password login.

so I wonder if I can use TCP/IP communicate with another computer and read the data from it without entering user name and password?

As I cannot find two computer to test it, i hope someone can answer me, who really has experienced on it. Thanks!

Cheers

Jimmy 

[SteveChandler]

TCP is just the transport. If you are using FTP the answer is one thing, if you are using RCP it is another thing. But basically with TCP you open a connection to a server (no password or username required) and send a string. The server responds with another string, you send a string back, etc. One string that the server sends you might be "username" and your program sends back the username. Then it responds back with "password" and you then send the password. If you sent the correct username and password then the server will accept strings such as "get filename.txt". It would respond with the contents of the file which is encoded using MIME or simply a hex encoded string. The protocol that I just described is completely ficticious.

We can give you answers on how to open TCP connections to servers and send and read strings. We can also help you with writing a TCP server. But first take a look at the TCP examples that ship with LabVIEW. What you might have trouble finding answers to is the protocols because they really have nothing to do with LabVIEW.

If you just want to copy a file then use the built in client/server protocols in your OS to copy files over the network. This way you only need to use the file copy functions that come with LabVIEW and can forget about the TCP stuff that happens in the background. Unless of course you want to learn about implementing protocols. If that is the case then see my comments in the previous paragraph

[Jimmyzeng]

Hi Steve,

it is very appreciated that your reply. 

you wrote that:"If you just want to copy a file then use the built in client/server protocols in your OS to copy files over the network. This way you only need to use the file copy functions that come with LabVIEW "

So how can I make a software to copy a file with only using the file copy functions that come with Labview?

Could you pls give me more detail? Thanks!

Br

Jimmy

[SteveChandler]

First you mount a network drive or something. Make sure you can just copy the file using Windows Explorer. Then you use the file copy VIs that come with LabVIEW. For some reason it is under Advanced File Functions.