How do I send a file to all the computers connected in a LAN network?

Ajinkya D September 27, 2013

Three questions:

  1. How do I broadcast a file to all the computers on a network, without opening multiple ports?
  2. Should I create a folder that is shared on the network, where all the computers on the network could copy data from this folder? Is my thinking conceptually right or am I mixing stuff?
  3. In a simple network how do computers talk to each other, using UNICAST method or BROADCAST method?

  1. Jan F
    September 28, 2013 at 3:20 pm

    Let me put it that way:
    Option 2 (sharing a folder) is going to be the easiest solution.

    Sharing a file via broadcast (option 1) is technically possible but you don't want to do that on any LAN as it will occupy the incoming data channel on all your devices, even your mobile phone if it is connected to WiFi and your router/AP doesn't filter the broadcast. Broadcasting should only be used for certain services e.g. ARP, DHCP.

    The option you'd be looking for is Multicast which uses a single data stream to send data to multiple recipients. However, unless your file is multiple GB in size, your network/application/service requires it or you are transferring it via a metered internet connection there is no real benefit to go through the hassle of setting it up.
    If you do want to try it out you should look into UDPcast or castcopy

    Unicast is a point-to-point connection to transfer data from one computer to another. So sharing a folder and copying files from or to it from another client is Unicast. Other examples of Unicast would be the http or ftp protocol.

  2. Oron J
    September 28, 2013 at 12:15 pm

    You could use a shared folder in Dropbox, or Bittorrent Sync. There are plenty of other ways too, it's really a question of why you want to do this, and what is required (for example, do they need to end up in a particular location? are they files of a particular type?).

  3. Hovsep A
    September 28, 2013 at 12:04 pm