i would be thankfull for an explanation what happens with HTTP(TCP/IP) transmissions when the server crashes unexpectedly, how does the client Browser (Firefox / IE) handle this event.
What happens in the following two standard cases:
Clients-actively sends data:
The TCP/IP Connection has been estableshed and the Client (Web-Browser) is Sending a POST Request with some data and in the middle of the process of sending the server crashes.
What does this mean for the client? As far as I know TCP/IP does not “acknowledge” a send data-package so the client does not know that the server crashed. How will the client behave? (Firefox and Internet Explorer)?
The Server is actively sending data:
As above the tcp/ip connection has been established and the Server is sending a large website to the client (browser). In the middle of the sending-process the server crashes, so no futher packets are sent. How does the client browser react to this event (Firefox and Interne Expolrer)
Thank you very much!!
Jens
Actually, it does. ACK-ing packets is how TCP can provide a reliable stream protocol on top of the unreliable IP.
If the browser doesn’t receive an ACK in a reasonable timeframe, it will try again (assuming that either the packet it sent or the response got lost en-route). After a number of failed attempts, it will time out the connection.
When receiving, if the client doesn’t receive any packets from the server for a long period of time, it will again time out the connection.