locked
Background transfer operations and resuming

    Question

  • Hi,

    I am searching for some documentation describing background transfer API behaviour especially what is happening with uploads after application termination or system shutdown. What will happen with download/upload in such case(termination, shutdown, connection problems) if operation can be resumed or restarted? Also, I wonder if there is any API which can be used to retry a download or upload after connection error?

    Saturday, May 31, 2014 4:18 PM

Answers

  • Hi ccoecontrol,

    This could be a good question.

    What will happen if download/upload timeout?

    Well, the answer is depends. There are two primary connection timeout scenarios to take into consideration:

    • When establishing a new connection for a transfer, the connection request is aborted if it is not established within five minutes.

    • After a connection has been established, an HTTP request message that has not received a response within two minutes is aborted.

    Note  In either scenario, assuming there is Internet connectivity, Background Transfer will retry a request up to three times automatically. In the event Internet connectivity is not detected, additional requests will wait until it is.

    Is there any API can retry the download or upload?

    Pause when no internet detect and Resume after connection established seems to be a good solution.

    --James


    <THE CONTENT IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND, WHETHER EXPRESS OR IMPLIED>
    Thanks
    MSDN Community Support

    Please remember to "Mark as Answer" the responses that resolved your issue. It is a common way to recognize those who have helped you, and makes it easier for other visitors to find the resolution later.

    Monday, June 2, 2014 3:34 AM
    Moderator

All replies

  • Hi ccoecontrol,

    This could be a good question.

    What will happen if download/upload timeout?

    Well, the answer is depends. There are two primary connection timeout scenarios to take into consideration:

    • When establishing a new connection for a transfer, the connection request is aborted if it is not established within five minutes.

    • After a connection has been established, an HTTP request message that has not received a response within two minutes is aborted.

    Note  In either scenario, assuming there is Internet connectivity, Background Transfer will retry a request up to three times automatically. In the event Internet connectivity is not detected, additional requests will wait until it is.

    Is there any API can retry the download or upload?

    Pause when no internet detect and Resume after connection established seems to be a good solution.

    --James


    <THE CONTENT IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND, WHETHER EXPRESS OR IMPLIED>
    Thanks
    MSDN Community Support

    Please remember to "Mark as Answer" the responses that resolved your issue. It is a common way to recognize those who have helped you, and makes it easier for other visitors to find the resolution later.

    Monday, June 2, 2014 3:34 AM
    Moderator
  • Hi James,

    Thanks for your response. The rules seems to be pretty clear. I just want to ask about next situation and expected behaviour that I am dealing with currently.

    So, when uploading with BackgroundUploader POST method the server is dropping connection after several MB of data uploadef. It looks just like a closed socket on server side, I do not have access to the server so I cannot say what is happening there actually. At least sniffer tools are reporting connection reset. There is no daat returned by the server.

    So my question is if in this case BackgroundUploader should retry whole operation?

    Are there any additional requirements that I have to meet?

    Does it differ if I would use PUT instead of POST?

    thanks in advance

    Tuesday, June 10, 2014 3:19 PM