Transport Layer - Freie Universität Berlin

TCP Flow Control: Sliding Window
● To provide reliable data transfer, as on Layer 2, a sliding window
mechanism is used.
Initial window
● Differences:
● Sender sends bytes
according to the window size
● Window is shifted by n byte
as soon as an ACK for n bytes
arrives
● Exception: Urgent data
(URGENT flag is set) are sent
immediately
● Characteristic:
the window size
can be changed
during the
transmission phase
1 2 3 4 5 6 7 8 9 10
Segment 1, 2, and 3 acknowledged
Window slides
1 2 3 4 5 6 7 8 9 10
Univ.-Prof. Dr.-Ing. Jochen H. Schiller ▪ cst.mi.fu-berlin.de ▪ Telematics ▪ Chapter 8: Transport Layer
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