Exit Zen
29
../../glossary.rst:285
English
A synonym for a regular telephone line, i.e. a line that can be used to dial any telephone number.
0/980 · 98
29
../../exercises/ex-sharing.rst:588
English
Simple network topology
0/230 · 23
29
../../exercises/network.rst:273
English
At this point, a new link is added between `R1` and `R3`. What happens for the forwarding of packets ?
0/1020 · 102
29
../../exercises/reliability.rst:62
English
The Cyclic Redundancy Checks (CRCs) are efficient error detection codes that are able to detect :
0/970 · 97
29
../../exercises/sockets.rst:270
English
The ``domain`` parameter specifies the address family that we will use to concretely perform the communication. For an IPv6 socket, the ``domain`` parameter will be set to the value ``AF_INET6``, telling the operating system that we plan to communicate using IPv6 addresses. The ``type`` parameter specifies the communication guarantees that we need. For now, we will use the type ``SOCK_DGRAM`` which allows us to send *unreliable messages*. This means that each data that we send at each call of ``sendto`` will either be completely received or not received at all. The last parameter will be set to ``0``. The following line creates a socket, telling the operating system that we want to communicate using IPv6 addresses and that we want to send unreliable messages.
0/7690 · 769
29
../../principles/network.rst:112
English
A path may lead to a `black hole`. In a network, a black hole is a router that receives packets for at least one given source/destination pair but does not have an entry inside its forwarding table for this destination. Since it does not know how to reach the destination, the router cannot forward the received packets and must discard them. Any centralized or distributed algorithm that computes forwarding tables must ensure that there are not black holes inside the network.
0/4780 · 478
29
../../principles/referencemodels.rst:119
English
transport layer entities exchange *segments*
0/440 · 44
29
../../principles/sharing.rst:145
English
Packets per second versus bits per second
0/410 · 41
29
../../principles/transport.rst:64
English
`z` : `1111010b`
0/160 · 16
30
../../bibliography.rst:97
English
Jung, J., Sit, E., Balakrishnan, H., and Morris, R. 2002. `DNS performance and the effectiveness of caching <https://dx.doi.org/10.1109/TNET.2002.803905>`_. IEEE/ACM Transactions Networking 10, 5 (Oct. 2002), 589-603.
0/2170 · 217
30
../../glossary.rst:54 • ../../glossary.rst:211 • ../../glossary.rst:232
English
DNS
0/100 · 3
30
../../exercises/ex-sharing.rst:591
English
Consider the simple network depicted in the figure below.
0/570 · 57
30
../../exercises/network.rst:276
English
The network below uses port forwarding tables. What happens if host `A` moves by removing its link with `R1` and replacing it with a link with `R3`? How should networks using port forwarding deal with such mobile hosts ?
0/2200 · 220
30
../../exercises/reliability.rst:64
English
all errors that affect an odd number of bits
0/440 · 44
30
../../exercises/sockets.rst:280
English
Sending a message to a remote peer using its IPv6 address
0/570 · 57
30
../../principles/network.rst:116
English
A second type of problem may exist in networks using the datagram organization. Consider a path that contains a cycle. For example, router `R1` sends all packets towards destination `D` via router `R2`. Router `R2` forwards these packets to router `R3` and finally router `R3`'s forwarding table uses router `R1` as its nexthop to reach destination `D`. In this case, if a packet destined to `D` is received by router `R1`, it will loop on the `R1 -> R2 -> R3 -> R1` cycle and will never reach its final destination. As in the black hole case, the destination is not reachable from all sources in the network. In practice the loop problem is more annoying than the black hole problem because when a packet is caught in a forwarding loop, it unnecessarily consumes bandwidth. In the black hole case, the problematic packet is quickly discarded. We will see later that network layer protocols include techniques to minimize the impact of such forwarding loops.
0/9580 · 958
30
../../principles/referencemodels.rst:120
English
application layer entities exchange *SDUs*
0/420 · 42
30
../../principles/transport.rst:65
English
`@` : `1000000b`
0/160 · 16
31
../../bibliography.rst:99
English
Kerrisk, M., `The Linux Programming Interface <http://nostarch.com/tlpi>`_, No Starch Press, 2010
0/970 · 97
31
../../exercises/ex-sharing.rst:609
English
In this network, a 250 Kbps link is used between the routers. The propagation delays in the network are negligible. Host `A` sends 1000 bits long segments so that it takes one msec to transmit one segment on the `A-R1` link. Neglecting the transmission delays for the acknowledgments, what is the minimum round-trip time measured on host `A` with such segments ?
0/3620 · 362