Exit Zen
7
../../exercises/routing-protocols.rst:94
English
Finally, we can start the IPMininet_ topology and launch the daemons. The entire script is available from :download:`/exercises/ipmininet_scripts/ospf6.py`.
0/1560 · 156
7
../../exercises/tcp-2.rst:22
English
packetdrill_ executes a system call and verifies its return value
0/650 · 65
7
../../exercises/trace.rst:35
English
A first solution to analyze this trace is to use tcpdump_ on the command line. The `-n` disables the reverse DNS lookups that tcpdump_ does by default for all IP addresses. The `-r` argument is the name of the file contained the captured packets. The trace starts with the DNS request. This request was sent over IPv4 which is the default on this host. tcpdump_ indicates the query and the response returned by the local DNS resolver.
0/4340 · 434
7
../../protocols/bgp.rst:27
English
Interconnection of two domains via a private peering link
0/570 · 57
7
../../protocols/congestion.rst:24
English
`mild congestion`. TCP considers that the network is lightly congested if it receives three duplicate acknowledgments and performs a fast retransmit. If the fast retransmit is successful, this implies that only one segment has been lost. In this case, TCP performs multiplicative decrease and the congestion window is divided by `2`. The slow-start threshold is set to the new value of the congestion window.
0/4080 · 408
7
../../protocols/dnssec.rst:53
English
The first field of the header is the `Identification` field. When Alice sends a DNS request, she places a 16-bits integer in this field and remembers it. When she receives a response, she uses this `Identification` field to locate the initial DNS request that she sent. The response is only used if its `Identification` matches a pending DNS request (containing the same question).
0/3810 · 381
7
../../protocols/email.rst:51
English
client software, that allows users to easily create and read email messages
0/750 · 75
7
../../protocols/ethernet.rst:56
English
Impact of the frame length on the maximum channel utilisation [SH1980]_
0/710 · 71
7
../../protocols/http.rst:18
English
In the late 1980s, high energy physicists working at CERN_ had to efficiently exchange documents about their ongoing and planned experiments. `Tim Berners-Lee`_ evaluated several of the documents sharing techniques that were available at that time [B1989]_. As none of the existing solutions met CERN's requirements, they chose to develop a completely new document sharing system. This system was initially called the `mesh`. It was quickly renamed the `world wide web`. The starting point for the `world wide web` are hypertext documents. An hypertext document is a document that contains references (hyperlinks) to other documents that the reader can immediately access. Hypertext was not invented for the world wide web. The idea of hypertext documents was proposed in 1945 [Bush1945]_ and the first experiments were done during the 1960s [Nelson1965]_ [Myers1998]_ . Compared to the hypertext documents that were used in the late 1980s, the main innovation introduced by the `world wide web` was to allow hyperlinks to reference documents stored on different remote machines.
0/10790 · 1079
7
../../protocols/http2.rst:53
English
Serving content from multiple servers
0/370 · 37
7
../../protocols/ipv6.rst:67
English
In the next chapter, we describe the organization and the operation of Local Area Networks. An important difference between the point-to-point datalink layers and the datalink layers used in LANs is that in a LAN, each communicating device is identified by a unique `datalink layer address`. This address is usually embedded in the hardware of the device and different types of LANs use different types of datalink layer addresses. Most LANs use 48-bits long addresses that are usually called `MAC` addresses. A communicating device attached to a LAN can send a datalink frame to any other communicating device that is attached to the same LAN. Most LANs also support special broadcast and multicast datalink layer addresses. A frame sent to the broadcast address of the LAN is delivered to all communicating devices that are attached to the LAN. The multicast addresses are used to identify groups of communicating devices. When a frame is sent towards a multicast datalink layer address, it is delivered by the LAN to all communicating devices that belong to the corresponding group.
0/10850 · 1085
7
../../protocols/ppp.rst:17
English
The `Point-to-Point Protocol` defines the framing technique to transport network layer packets.
0/950 · 95
7
../../protocols/ppp.rst:19
English
The `Network Control Protocol` that is specific for each network layer protocol. It is used to negotiate options that are specific for each protocol. For example, IPv4's NCP :rfc:`1548` can negotiate the IPv4 address to be used, the IPv4 address of the DNS resolver. IPv6's NCP is defined in :rfc:`5072`.
0/3040 · 304
7
../../protocols/routing.rst:23
English
A very important difference between intradomain and interdomain routing are the `routing policies` that are used by each domain. Inside a single domain, all routers are considered equal, and when several routes are available to reach a given destination prefix, the best route is selected based on technical criteria such as the route with the shortest delay, the route with the minimum number of hops or the route with the highest bandwidth.
0/4420 · 442
7
../../protocols/rpc.rst:15
English
The callee places the return value(s) at a location (register, stack, ...) where the caller can access them
0/1070 · 107
7
../../protocols/ssh.rst:70
English
The next message is the ``SSH_MSG_KEX_INIT`` message that is used to negotiate the cryptographic algorithms that will be used for the ``ssh`` session. It is very important for security protocols to include mechanisms that enable a negotiation of the cryptographic algorithms that are used. First, these algorithms provide different levels of security. Some algorithms might be considered totally secure and are recommended today while they could become deprecated a few years later after the publication of some attacks. Second, these algorithms provide different levels of performance and have different CPU and memory impacts.
0/6280 · 628
7
../../protocols/tcp.rst:19
English
remote computer access : :term:`telnet`, :term:`ssh`, :term:`X11`, :term:`VNC`, ...
0/830 · 83
7
../../protocols/tls.rst:41
English
TCP port
0/100 · 8
7
../../protocols/transport-service.rst:17
English
the `host` on which the application is running
0/460 · 46
7
../../protocols/udp.rst:19
English
The figure below shows a typical usage of the UDP port numbers. The client process uses port number `1234` while the server process uses port number `5678`. When the client sends a request, it is identified as originating from port number `1234` on the client host and destined to port number `5678` on the server host. When the server process replies to this request, the server's UDP implementation will send the reply as originating from port `5678` on the server host and destined to port `1234` on the client host.
0/5200 · 520