Task 2; Data Link Made. We will look at so-called "Automatic repeat request" (ARQ) protocols: a) Why is it necessary to use flow control in the ARQ protocols? b) How does the ARQ protocol correct transmission errors? c) What is the purpose of "alarm clock" (hours) on the transmitter page in systems like using ARQ? d) In a Stop-and-Wait ARQ system, the bandwidth of line 1Mb / s, and a bit has a round trip time of 20ms. If the data frames are 1000 bit long, what is the percentage utilization of the link?

Task 3; network Layer Data that the network layer will transfer for the transport layer will often not fit in a package. In such cases, the network layer will use multiple packages to transfer the data to the target. There are several steps to make it happen. a) What is the difference between transparent and non-transparent segmentation? b) What opportunity is used on the Internet?