2. cnp3-ebook
3. English
4. Zen

49 ../../principles/sharing.rst:344
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — Delays, packet discards, packet markings and control packets are the main types of information that the network can exchange with the end hosts. Discarding packets is the main action that a network node can perform if the congestion is too severe. Besides tackling congestion at each node, it is also possible to divert some traffic flows from heavily loaded links to reduce congestion. Early routing algorithms [MRR1980]_ have used delay measurements to detect congestion between network nodes and update the link weights dynamically. By reflecting the delay perceived by applications in the link weights used for the shortest paths computation, these routing algorithms managed to dynamically change the forwarding paths in reaction to congestion. However, deployment experience showed that these dynamic routing algorithms could cause oscillations and did not necessarily lower congestion. Deployed datagram networks rarely use dynamic routing algorithms, except in some wireless networks. In datagram networks, the state of the art reaction to long term congestion, i.e. congestion lasting hours, days or more, is to measure the traffic demand and then select the link weights [FRT2002]_ that allow minimizing the maximum link loads. If the congestion lasts longer, changing the weights is not sufficient anymore and the network needs to be upgraded with additional or faster links. However, in Wide Area Networks, adding new links can take months. 1452/10000 · 1452
50 ../../exercises/sockets.rst:350
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — Here are some exercises that will help you to learn how to use sockets. 71/10000 · 71
50 ../../bibliography.rst:70
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — Fletcher, J., `An Arithmetic Checksum for Serial Transmissions <https://dx.doi.org/10.1109/TCOM.1982.1095369>`_, Communications, IEEE Transactions on, Jan. 1982, Vol. 30, N. 1, pp. 247-252 188/10000 · 188
50 ../../exercises/network.rst:372 • ../../exercises/network.rst:374
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — 2 via B 7/10000 · 7
50 ../../glossary.rst:299
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — hosts.txt 9/10000 · 9
50 ../../principles/reliability.rst:224
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — Given that multi-symbol encodings cannot be used by all physical layers, a generic solution which can be used with any physical layer that is able to transmit and receive only bits `0` and `1` is required. This generic solution is called `stuffing` and two variants exist : `bit stuffing` and `character stuffing`. To enable a receiver to easily delineate the frame boundaries, these two techniques reserve special bit strings as frame boundary markers and encode the frames so that these special bit strings do not appear inside the frames. 541/10000 · 541
50 ../../principles/sharing.rst:346
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — In virtual circuit networks, another way to manage or prevent congestion is to limit the number of circuits that use the network at any time. This technique is usually called `connection admission control`. When a host requests the creation of a new circuit in the network, it specifies the destination and in some networking technologies the required bandwidth. With this information, the network can check whether there are enough resources available to reach this particular destination. If yes, the circuit is established. If not, the request is denied and the host will have to defer the creation of its virtual circuit. `Connection admission control` schemes are widely used in the telephone networks. In these networks, a busy tone corresponds to an unavailable destination or a congested network. 804/10000 · 804
50 ../../principles/transport.rst:158
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — Most networks use a datagram organization and provide a simple service which is called the `connectionless service`. 116/10000 · 116
50 ../../principles/security.rst:478
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — A naive approach would be to rely on hash functions. Since hash functions are non-invertible, Alice and Bob could decide to use them to exchange Alice's password in a secure manner. Then, Alice could be authenticated by using the following exchange. 249/10000 · 249
50 ../../exercises/ipv6.rst:481
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — The packets whose destinations are ``A1``, ``A2``, ``B1`` or ``B2`` are never forwarded via router ``R4`` 106/10000 · 106
50 ../../exercises/routing-protocols.rst:598
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — Besides :manpage:`ping6(8)` and :manpage:`traceroute6(8)`, it is also useful to interact with the BGP daemon that runs on each of our routers. This is done by connecting on the Command Line Interface of the BGP router using telnet. 231/10000 · 231
50 ../../exercises/tcp-2.rst:646
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — the value of the duplicate acknowledgment threshold is fixed and set to 3 73/10000 · 73
50 ../../protocols/bgp.rst:159
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — In this figure, the router receives BGP messages on the left part of the figure, processes these messages and possibly sends BGP messages on the right part of the figure. A BGP router contains three important data structures : 226/10000 · 226
50 ../../protocols/congestion.rst:225
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — `CUBIC`, which was designed for high bandwidth links and is the default congestion control scheme in Linux since the Linux 2.6.19 kernel [HRX2008]_. It is now used by several operating systems and is becoming the default congestion control scheme :rfc:`8312`. A key difference between CUBIC and the TCP congestion control scheme described in this chapter is that CUBIC is much more aggressive when probing the network. Instead of relying on additive increase after a fast recovery, a CUBIC sender adjusts its congestion by using a cubic function. Thanks to this function, the congestion windows grows faster. This is particularly important in high-bandwidth delay networks. 673/10000 · 673
50 ../../protocols/email.rst:230 • ../../protocols/email.rst:230 • ../../protocols/email.rst:230 • ../../protocols/email.rst:230 • ../../protocols/email.rst:278 • ../../protocols/email.rst:297 • ../../protocols/email.rst:311
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — Encoding 8/10000 · 8
50 ../../protocols/ethernet.rst:195
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — Initially, the OUIs were allocated by Xerox [DP1981]_. However, once Ethernet became an IEEE and later an ISO standard, the allocation of the OUIs moved to IEEE. The list of all OUI allocations may be found at http://standards.ieee.org/regauth/oui/index.shtml 259/10000 · 259
50 ../../protocols/http.rst:175
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — The importance of the `Host:` header line 41/10000 · 41
50 ../../protocols/ipv6.rst:174
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — In practice, there are several types of IPv6 unicast address. Most of the `IPv6 unicast addresses <http://www.iana.org/assignments/ipv6-address-space/ipv6-address-space.xhtml>`_ are allocated in blocks under the responsibility of IANA_. The current IPv6 allocations are part of the `2000::/3` address block. Regional Internet Registries (RIR) such as RIPE_ in Europe, ARIN_ in North-America or AfriNIC in Africa have each received a `block of IPv6 addresses <http://www.iana.org/assignments/ipv6-unicast-address-assignments/ipv6-unicast-address-assignments.xhtml>`_ that they sub-allocate to Internet Service Providers in their region. The ISPs then sub-allocate addresses to their customers. 694/10000 · 694
50 ../../protocols/ethernet.rst:174
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — 10 Mb/s over optical fiber 26/10000 · 26
50 ../../protocols/routing.rst:158
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — To efficiently spread the load over different paths, routers need to implement `per-flow` load-balancing. This implies that they must forward all the packets that belong to the same flow on the same path. Since a TCP connection is always identified by the four-tuple (source and destination addresses, source and destination ports), one possibility would be to select an outgoing interface upon arrival of the first packet of the flow and store this decision in the router's memory. Unfortunately, such a solution does not scale since the required memory grows with the number of TCP connections that pass through the router. 625/10000 · 625