Exit Zen
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../../exercises/ex-sharing.rst:175
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Same question as above, but now assume that the retransmission timer of each host is set to 50 microseconds.
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../../exercises/network.rst:96
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the router located in `New York`
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../../exercises/sockets.rst:110
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Sending data to a peer using a socket
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../../exercises/transport.rst:86
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Same question as above, but consider now that the transport protocol tries to send large DATA segments whenever possible. For this exercise, we consider that a DATA segment can contain up to 8 bytes of data in the payload. Do not forget to show the acknowledgments in your answer.
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../../principles/naming.rst:54
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The syntax of the domain names has been defined more precisely in :rfc:`1035`. This document recommends the following :term:`BNF` for fully qualified domain names (the domain names themselves have a much richer syntax).
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../../principles/referencemodels.rst:38
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the Physical layer may change, e.g. due to electromagnetic interference, the value of a bit being transmitted
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../../principles/network.rst:35
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As a first step, let us assume that we only need to exchange a small amount of data. In this case, there is no issue with the maximum length of the frames. However, there are other more interesting problems that we need to tackle. To understand these problems, let us consider the network represented in the figure below.
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../../principles/reliability.rst:44 • ../../principles/reliability.rst:49
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Bit rate
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../../principles/transport.rst:30
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Bob : `Hello`
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../../protocols/dns.rst:40
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The `RD` (recursion desired) bit is set by a client when it sends a query to a resolver. Such a query is said to be `recursive` because the resolver will recursively traverse the DNS hierarchy to retrieve the answer on behalf of the client. In the past, all resolvers were configured to perform recursive queries on behalf of any Internet host. However, this exposes the resolvers to several security risks. The simplest one is that the resolver could become overloaded by having too many recursive queries to process. Most resolvers [#f8888]_ only allow recursive queries from clients belonging to their company or network and discard all other recursive queries. The `RA` bit indicates whether the server supports recursion. The `RCODE` is used to distinguish between different types of errors. See :rfc:`1035` for additional details. The last four fields indicate the size of the `Question`, `Answer`, `Authority` and `Additional` sections of the DNS message.
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../../principles/security.rst:132
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Pervasive monitoring
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../../exercises/dns.rst:37
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`fqdn` is the fully qualified domain name being queried
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../../exercises/email.rst:22
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On smartphones, users often want to avoid downloading large emails over a slow wireless connection. How could a POP client only download emails that are smaller than 5 KBytes ?
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../../exercises/http.rst:29
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Compare the size of the http://www.yahoo.com and http://www.google.com web pages by downloading them with curl_.
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../../exercises/ipv6.rst:38 • ../../exercises/ipv6.rst:147 • ../../exercises/ipv6.rst:225
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The routers have one address inside each network :
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../../exercises/lan.rst:70
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Fig. 3. Host `H0` performs a traceroute towards its peer `H1` through a network composed of switches and routers
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../../exercises/routing-policies.rst:128
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In this internet, some ASes cannot reach all other ASes. Can you fix the problem by adding one shared-cost peering link or one customer-provider peering link ?
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../../exercises/routing-protocols.rst:135
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We can also connect to the OSPFv3 daemon running on the routers to observe its state. For this, we use the ``noecho r1 telnet localhost ospf6d`` command.
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../../exercises/tcp-2.rst:26
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For our first packetdrill_ script, we aim at reproducing the simple connection shown in the figure below.
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../../exercises/trace.rst:62
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The server then sends its response, which fits inside a single segment. The client acknowledges the reception of this segment.
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