Exit Zen
144
../../glossary.rst:318
English
A service that enables a user to connect to a distant server over the network. Telnet, defined in :rfc:`854` and the BSD rlogin services defined in :rfc:`1282` were popular in the past. They have been deprecated for security reasons and are now replaced by :term:`ssh`.
0/2690 · 269
144
../../principles/dv.rst:94
English
Consider the example above and assume that the link between routers `A` and `B` fails. Before the failure, `A` used `B` to reach destinations `B`, `C` and `E` while `B` only used the `A-B` link to reach `A`. The two routers detect the failure by the timeouts in the affected entries in their routing tables. Both routers `A` and `B` send their distance vector.
0/3600 · 360
144
../../principles/reliability.rst:461
English
Reliable protocols use error detection schemes, but none of the widely used reliable protocols rely on error correction schemes. To detect errors, a frame is usually divided into two parts :
0/1900 · 190
144
../../principles/transport.rst:769
English
The receiver may adjust its advertised receive window based on its current memory consumption, but also to limit the bandwidth used by the sender. In practice, the receive buffer can also shrink as the application may not able to process the received data quickly enough. In this case, the receive buffer may be completely full and the advertised receive window may shrink to `0`. When the sender receives an acknowledgment with a receive window set to `0`, it is blocked until it receives an acknowledgment with a positive receive window. Unfortunately, as shown in the figure below, the loss of this acknowledgment could cause a deadlock as the sender waits for an acknowledgment while the receiver is waiting for a data segment.
0/7310 · 731
144
../../principles/sharing.rst:688
English
Congestion control
0/180 · 18
144
../../protocols/email.rst:256
English
/
0/100 · 1
144
../../protocols/ipv6.rst:455
English
The following pseudo-code details the IPv6 fragmentation, assuming that the packet does not contain options.
0/1080 · 108
144
../../protocols/wifi.rst:22
English
2 Mbps
0/100 · 6
144
../../protocols/tcp.rst:430
English
:math:`rto=srtt + 4 \times rttvar`
0/340 · 34
145
../../glossary.rst:247
English
resolver
0/100 · 8
145
../../principles/dv.rst:96
English
`A` sends its distance vector :math:`[A=0,B=\infty,C=\infty,D=1,E=\infty]`. `D` knows that it cannot reach `B` anymore via `A`
0/1260 · 126
145
../../principles/reliability.rst:463
English
a `header` that contains the fields used by the reliable protocol to ensure reliable delivery. The header contains a checksum or Cyclical Redundancy Check (CRC) [Williams1993]_ that is used to detect transmission errors
0/2190 · 219
145
../../principles/transport.rst:775
English
Risk of deadlock with dynamic windows
0/370 · 37
145
../../principles/sharing.rst:690
English
Most networks contain links having different bandwidth. Some hosts can use low bandwidth wireless networks. Some servers are attached via 10 Gbps interfaces and inter-router links may vary from a few tens of kilobits per second up to hundred Gbps. Despite these huge differences in performance, any host should be able to efficiently exchange segments with a high-end server.
0/3750 · 375
145
../../protocols/email.rst:258
English
13
0/100 · 2
145
../../protocols/ipv6.rst:490
English
In the above pseudocode, we maintain a single 32 bits counter that is incremented for each packet that needs to be fragmented. Other implementations to compute the packet identification are possible. :rfc:`2460` only requires that two fragmented packets that are sent within the MSL between the same pair of hosts have different identifications.
0/3450 · 345
145
../../protocols/wifi.rst:22
English
20/100
0/100 · 6
145
../../protocols/tcp.rst:432
English
The proposed values for the parameters are :math:`\alpha=\frac{1}{8}` and :math:`\beta=\frac{1}{4}`. This allows a TCP implementation, implemented in the kernel, to perform the `rtt` computation by using shift operations instead of the more costly floating point operations [Jacobson1988]_. The figure below illustrates the computation of the `rto` upon `rtt` changes.
0/3680 · 368
146
../../glossary.rst:249
English
A server that implements the DNS protocol and can resolve queries. A resolver usually serves a set of clients (e.g. all hosts in campus or all clients of a given ISP). It sends DNS queries to nameservers everywhere on behalf of its clients and stores the received answers in its cache. A resolver must know the IP addresses of the root nameservers.
0/3480 · 348
146
../../principles/dv.rst:97
English
`D` sends its distance vector :math:`[D=0,B=\infty,A=1,C=2,E=1]` to `A` and `E`. `A` recovers routes towards `C` and `E` via `D`.
0/1290 · 129