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Old 29th May 2008
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jggimi jggimi is offline
More noise than signal
Join Date: May 2008
Location: USA
Posts: 6,446

Did you read what I wrote about this "service"?

A userid/pw and domain name are insufficient information, unless this service, whatever it is, is designed to be run from a browser.

You seem to lack a basic understanding of TCP/IP networking. If that is so, perhaps this extremely brief and absolutely incomplete overview will be helpful.
You may be aware that the Domain Name System, DNS, converts domain names to IP addresses. An IP address is used to route packets of information from one computer to another.

There are many many types of packets. You can see a list of many of these in /etc/protocols. Among the two most commonly used protocols are TCP and UDP. They are, however, only two of many. They are used for all sorts of general communication. The major difference between these two common protocols is that UDP is stateless -- a UDP packet can be sent and never acknowledged. TCP, though establishes state -- a connection is established and packets are acknowledged back and forth.

Unlike the many other protocols, UDP and TCP both use the concept of "ports". A service on a server listens for incoming packets on a particular TCP or UDP port. Some ports are standard, such as 53 for DNS, 80 for HTTP, 21 for FTP, and so on. These numbers may be familiar to you.

But this is at a lower level than applications. For example, UDP port 53 is used by DNS servers, and TCP port 80 is used by web servers, but the data in the packets is entirely different. The protocols are widely used because they just specify how to send raw data. The applications at each end must know what that data is. For example, with VPNs, both SSH and OpenVPN can use TCP for transferring packets. But they have independent protocols and are in no way compatible. So, even knowing a port number or IP protocol is not enough information to connect to a service.
When you provide nothing but a domain name and userid/pw, as you did above, you tell us nothing about a networking service. Unless that service happens to be a web server, you leave it to us to research your friend's facilities. None of us want to do that, and, as I'm typing this from inside a corporate firewall, I cannot. I would be unwilling to do so even if I had a clear Internet connection.

You must contact your friend and find out:
  1. What is this service?
  2. What IP protocol is used?
  3. If TCP/UDP is/are the IP protocol(s) involved, what ports are used?
  4. What is the higher level protocol?
Do your homework.

Last edited by jggimi; 29th May 2008 at 06:10 PM. Reason: clarity
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