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138 ../../principles/reliability.rst:472 • ../../principles/reliability.rst:489
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — 011 3/10000 · 3
138 ../../principles/transport.rst:820
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — `Go-back-n` and `selective repeat` can be used in the transport layer as in the datalink layer. Since the network layer does not guarantee an in-order delivery of the packets, a transport entity should always store the segments that it receives out-of-sequence. For this reason, most transport protocols will opt for some form of selective repeat mechanism. 357/10000 · 357
138 ../../principles/sharing.rst:829
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — To understand this problem better, let us consider the scenario shown in the figure below, where a server (`A`) attached to a `10 Mbps` link needs to reliably transfer segments to another computer (`C`) through a path that contains a `2 Mbps` link. 248/10000 · 248
138 ../../protocols/bgp.rst:484
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — The BGP sessions and the underlying TCP connection are typically established by the routers when they boot based on information found in their configuration. The BGP sessions are rarely released, except if the corresponding peering link fails or one of the endpoints crashes or needs to be rebooted. 299/10000 · 299
138 ../../protocols/email.rst:256
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — M 1/10000 · 1
138 ../../protocols/ipv6.rst:437
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — the `Fragment Offset` is a 13-bit unsigned integer that contains the offset, in 8 bytes units, of the data following this header, relative to the start of the original packet. 175/10000 · 175
138 ../../protocols/wifi.rst:19
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — Typical throughput 18/10000 · 18
138 ../../protocols/tcp.rst:407
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — `rto` : the retransmission timeout is computed as :math:`rto=\min(60,max(1,\beta \times srtt))` where :math:`\beta` is used to take into account the delay variance (value : 1.3 to 2.0). The `60` and `1` constants are used to ensure that the `rto` is not larger than one minute nor smaller than 1 second. 303/10000 · 303
138 ../../bibliography.rst:345
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — Stevens, R., `TCP/IP Illustrated : the Protocols <http://books.google.com/books?id=-btNds68w84C>`_, Addison-Wesley, 1994 120/10000 · 120
139 ../../bibliography.rst:346
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — Stevens, R., `UNIX Network Programming, Volume 1, Second Edition: Networking APIs: Sockets and XTI <http://books.google.com/books?id=ptSC4LpwGA0C>`_, Prentice Hall, 1998 169/10000 · 169
139 ../../glossary.rst:304
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — 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`. 269/10000 · 269
139 ../../principles/dv.rst:122
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — `E` sends its distance vector `[E=0,D=1,A=2,C=1]` to `D`, `B` and `C`. `B` can now reach `A`, `C`, `D` and `E` 110/10000 · 110
139 ../../principles/reliability.rst:475
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — The parity bit allows a receiver to detect transmission errors that have affected a single bit among the transmitted `N+r` bits. If there are two or more bits in error, the receiver may not necessarily be able to detect the transmission error. More powerful error detection schemes have been defined. The Cyclical Redundancy Checks (CRC) are widely used in datalink layer protocols. An N-bits CRC can detect all transmission errors affecting a burst of less than N bits in the transmitted frame and all transmission errors that affect an odd number of bits. Additional details about CRCs may be found in [Williams1993]_. 620/10000 · 620
139 ../../principles/transport.rst:822
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — In the datalink layer, the sliding window has usually a fixed size which depends on the amount of buffers allocated to the datalink layer entity. Such a datalink layer entity usually serves one or a few network layer entities. In the transport layer, the situation is different. A single transport layer entity serves a large and varying number of application processes. Each transport layer entity manages a pool of buffers that needs to be shared between all these processes. Transport entity are usually implemented inside the operating system kernel and shares memory with other parts of the system. Furthermore, a transport layer entity must support several (possibly hundreds or thousands) of transport connections at the same time. This implies that the memory which can be used to support the sending or the receiving buffer of a transport connection may change during the lifetime of the connection [#fautotune]_ . Thus, a transport protocol must allow the sender and the receiver to adjust their window sizes. 1019/10000 · 1019
139 ../../principles/sharing.rst:847
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — In this network, the segments sent by the server reach router `R1`. `R1` forwards the segments towards router `R2`. Router `R1` can potentially receive segments at `10 Mbps`, but it can only forward them at `2 Mbps` to router `R2` and then to host `C`. Router `R1` includes buffers that allow it to store the packets that cannot immediately be forwarded to their destination. To understand the operation of a reliable transport protocol in this environment, let us consider a simplified model of this network where host `A` is attached to a `10 Mbps` link to a queue that represents the buffers of router `R1`. This queue is emptied at a rate of `2 Mbps`. 656/10000 · 656
139 ../../protocols/bgp.rst:486
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — 90 seconds is the default delay recommended by :rfc:`4271`. However, two BGP peers can negotiate a different timer during the establishment of their BGP session. Using a too small interval to detect BGP session failures is not recommended. BFD [KW2009]_ can be used to replace BGP's KEEPALIVE mechanism if fast detection of interdomain link failures is required. 362/10000 · 362
139 ../../protocols/email.rst:256
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — 29 2/10000 · 2
139 ../../protocols/ipv6.rst:438
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — the `More` flag, which is set to `0` in the last fragment of a packet and to `1` in all other fragments. 104/10000 · 104
139 ../../protocols/wifi.rst:19
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — Max bandwidth 13/10000 · 13
139 ../../protocols/tcp.rst:409
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — However, in practice, this computation for the retransmission timeout did not work well. The main problem was that the computed `rto` did not correctly take into account the variations in the measured round-trip-time. `Van Jacobson` proposed in his seminal paper [Jacobson1988]_ an improved algorithm to compute the `rto` and implemented it in the BSD Unix distribution. This algorithm is now part of the TCP standard :rfc:`2988`. 430/10000 · 430