2. cnp3-ebook
3. exercises/tcp-2
4. English
5. Zen

59 ../../exercises/tcp-2.rst:740
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — In question 1, we assumed that the receiver acknowledged every segment received from the sender. In practice, many deployed TCP implementations use delayed acknowledgments. Assuming a delayed acknowledgment timer of 50 milliseconds, modify the time-sequence diagram below to reflect the impact of these delayed acknowledgment. Does their usage decreases or increased the transmission delay ? 391/10000 · 391
60 ../../exercises/tcp-2.rst:775
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — Let us now explore the impact of congestion on the slow-start and congestion avoidance mechanisms. Consider the scenario below. For graphical reasons, it is not possible anymore to show information about the segments on the graph, but you can easily infer them. 261/10000 · 261
61 ../../exercises/tcp-2.rst:832
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — Redraw the same figure assuming that the second segment that was delivered by the sender in the figure experienced congestion. In a network that uses Explicit Congestion Notification, this segment would be marked by routers and the receiver would return the congestion mark in the corresponding acknowledgment. 310/10000 · 310
62 ../../exercises/tcp-2.rst:834
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — Same question, but assume now that the fourth segment delivered by the sender experienced congestion (but was not discarded). 125/10000 · 125
63 ../../exercises/tcp-2.rst:837
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — A TCP connection has been active for some time and has reached a congestion window of 4000 bytes. Four segments are sent, but the second (shown in red in the figure) is corrupted. Complete the time-sequence diagram. 215/10000 · 215
64 ../../exercises/tcp-2.rst:871
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — Footnotes 9/10000 · 9
65 ../../exercises/tcp-2.rst:876
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — On Linux, most of the parameters to tune the TCP stack are accessible via :manpage:`sysctl`. These parameters are briefly described in https://github.com/torvalds/linux/blob/master/Documentation/networking/ip-sysctl.txt and in the :manpage:`tcp` manpage. Each script sets some of these configuration variables. 310/10000 · 310
66 ../../exercises/tcp-2.rst:883
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — packetdrill_ requires root privileges since it inject raw IP packets. The easiest way to install it is to use a virtualbox image with a Linux kernel 4.x or 5.x. You can clone its git repository from https://github.com/google/packetdrill and follow the instructions in https://github.com/google/packetdrill/tree/master/gtests/net/packetdrill. The packetdrill_ scripts used in this section are available from https://github.com/cnp3/ebook/tree/master/exercises/packetdrill_scripts 478/10000 · 478
67 ../../exercises/tcp-2.rst:885
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — By default, packetdrill_ uses port 8080 when creating TCP segments. You can thus capture the packets injected by packetdrill_ and the responses from the stack by using ``tcpdump -i any -n port 8080`` 199/10000 · 199
68 ../../exercises/tcp-2.rst:887
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — The `Push` flag is one of the TCP flags defined in :rfc:`793`. TCP stacks usually set this flag when transmitting a segment that empties the send buffer. This is the reason why we observe this push flag in our example. 218/10000 · 218
69 ../../exercises/tcp-2.rst:889
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — The variables that are included in TCP_INFO are defined in https://github.com/torvalds/linux/blob/master/include/uapi/linux/tcp.h 129/10000 · 129
70 ../../exercises/tcp-2.rst:891
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — These states are defined in https://github.com/torvalds/linux/blob/master/include/net/tcp_states.h 98/10000 · 98
The translation has come to an end.