msgid "" msgstr "" "Project-Id-Version: French (cnp3-ebook)\n" "Report-Msgid-Bugs-To: \n" "POT-Creation-Date: 2026-04-19 04:34+0200\n" "PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n" "Last-Translator: FULL NAME \n" "Language-Team: French \n" "Language: fr\n" "MIME-Version: 1.0\n" "Content-Type: text/plain; charset=UTF-8\n" "Content-Transfer-Encoding: 8bit\n" "Plural-Forms: nplurals=2; plural=n > 1;\n" "X-Generator: Weblate 5.14.3\n" #: ../../protocols/transport-service.rst:6 msgid "The application layer" msgstr "La couche application" #: ../../protocols/transport-service.rst:8 msgid "" "Networked applications rely on the transport service. As explained earlier, " "there are two main types of transport services :" msgstr "" #: ../../protocols/transport-service.rst:10 msgid "the `connectionless` service" msgstr "" #: ../../protocols/transport-service.rst:11 msgid "the `connection-oriented` or `byte-stream` service" msgstr "" #: ../../protocols/transport-service.rst:13 msgid "" "The connectionless service allows applications to easily exchange messages " "or Service Data Units. On the Internet, this service is provided by the UDP " "protocol that will be explained in the next chapter. The connectionless " "transport service on the Internet is unreliable, but is able to detect " "transmission errors. This implies that an application will not receive data " "that has been corrupted due to transmission errors." msgstr "" #: ../../protocols/transport-service.rst:15 msgid "" "The connectionless transport service allows networked application to " "exchange messages. Several networked applications may be running at the same " "time on a single host. Each of these applications must be able to exchange " "SDUs with remote applications. To enable these exchanges of SDUs, each " "networked application running on a host is identified by the following " "information :" msgstr "" #: ../../protocols/transport-service.rst:17 msgid "the `host` on which the application is running" msgstr "" #: ../../protocols/transport-service.rst:18 msgid "the `port number` on which the application `listens` for SDUs" msgstr "" #: ../../protocols/transport-service.rst:20 msgid "" "On the Internet, the `port number` is an integer and the `host` is " "identified by its network address. There are two types of Internet addresses " ":" msgstr "" #: ../../protocols/transport-service.rst:22 msgid "`IP version 4` addresses that are 32 bits wide" msgstr "" #: ../../protocols/transport-service.rst:23 msgid "`IP version 6` addresses that are 128 bits wide" msgstr "" #: ../../protocols/transport-service.rst:25 msgid "" "IPv4 addresses are usually represented by using a dotted decimal " "representation where each decimal number corresponds to one byte of the " "address, e.g. `203.0.113.56`. IPv6 addresses are usually represented as a " "set of hexadecimal numbers separated by semicolons, e.g. " "`2001:db8:3080:2:217:f2ff:fed6:65c0`. Today, most Internet hosts have one " "IPv4 address. A small fraction of them also have an IPv6 address. In the " "future, we can expect that more and more hosts will have IPv6 addresses and " "that some of them will not have an IPv4 address anymore. A host that only " "has an IPv4 address cannot communicate with a host having only an IPv6 " "address. The figure below illustrates two applications that are using the " "datagram service provided by UDP on hosts that are using IPv4 addresses." msgstr "" #: ../../protocols/transport-service.rst:47 msgid "Textual representation of IPv6 addresses" msgstr "" #: ../../protocols/transport-service.rst:49 msgid "" "It is sometimes necessary to write IPv6 addresses in text format, e.g. when " "manually configuring addresses or for documentation purposes. The preferred " "format for writing IPv6 addresses is `x:x:x:x:x:x:x:x`, where the `x` 's are " "hexadecimal digits representing the eight 16-bit parts of the address. Here " "are a few examples of IPv6 addresses :" msgstr "" #: ../../protocols/transport-service.rst:51 msgid "`abcd:ef01:2345:6789:abcd:ef01:2345:6789`" msgstr "" #: ../../protocols/transport-service.rst:52 msgid "`2001:db8:0:0:8:800:200c:417a`" msgstr "" #: ../../protocols/transport-service.rst:53 msgid "`fe80:0:0:0:219:e3ff:fed7:1204`" msgstr "" #: ../../protocols/transport-service.rst:56 msgid "" "IPv6 addresses often contain a long sequence of bits set to `0`. In this " "case, a compact notation has been defined. With this notation, `::` is used " "to indicate one or more groups of 16 bits blocks containing only bits set to " "`0`. For example," msgstr "" #: ../../protocols/transport-service.rst:58 msgid "" "`2001:db8:0:0:8:800:200c:417a` is represented as `2001:db8::8:800:200c:417a`" msgstr "" #: ../../protocols/transport-service.rst:59 msgid "`ff01:0:0:0:0:0:0:101` is represented as `ff01::101`" msgstr "" #: ../../protocols/transport-service.rst:60 msgid "`0:0:0:0:0:0:0:1` is represented as `::1`" msgstr "" #: ../../protocols/transport-service.rst:61 msgid "`0:0:0:0:0:0:0:0` is represented as `\\:\\:`" msgstr "" #: ../../protocols/transport-service.rst:65 msgid "" "The second transport service is the connection-oriented service. On the " "Internet, this service is often called the `byte-stream service` as it " "creates a reliable byte stream between the two applications that are linked " "by a transport connection. Like the datagram service, the networked " "applications that use the byte-stream service are identified by the host on " "which they run and a port number. These hosts can be identified by an " "address or a name. The figure below illustrates two applications that are " "using the byte-stream service provided by the TCP protocol on IPv6 hosts. " "The byte stream service provided by TCP is reliable and bidirectional." msgstr ""