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178 ../../principles/reliability.rst:890
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — A `go-back-n` sender is also very simple. It uses a sending buffer that can store an entire sliding window of frames [#fsizesliding]_. The frames are sent with increasing sequence numbers (modulo `maxseq`). The sender must wait for an acknowledgment once its sending buffer is full. When a `go-back-n` sender receives an acknowledgment, it removes from the sending buffer all the acknowledged frames and uses a retransmission timer to detect frame losses. A simple `go-back-n` sender maintains one retransmission timer per connection. This timer is started when the first frame is sent. When the `go-back-n sender` receives an acknowledgment, it restarts the retransmission timer only if there are still unacknowledged frames in its sending buffer. When the retransmission timer expires, the `go-back-n` sender assumes that all the unacknowledged frames currently stored in its sending buffer have been lost. It thus retransmits all the unacknowledged frames in the buffer and restarts its retransmission timer. 1011/10000 · 1011
179 ../../glossary.rst:83
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — refers to the :term:`TCP` and :term:`IP` protocols 50/10000 · 50
179 ../../principles/reliability.rst:932
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — The operation of `go-back-n` is illustrated in the figure below. In this figure, note that upon reception of the out-of-sequence frame `D(2,c)`, the receiver returns a cumulative acknowledgment `C(OK,0)` that acknowledges all the frames that have been received in sequence. The lost frame is retransmitted upon the expiration of the retransmission timer. 354/10000 · 354
179 ../../principles/sharing.rst:1411
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — In practice, a router is connected to multiple input links. The figure below shows an example with two hosts. 109/10000 · 109
179 ../../protocols/email.rst:286
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — The last point to be discussed about `base64` is what happens when the length of the sequence of bytes to be encoded is not a multiple of three. In this case, the last group of bytes may contain one or two bytes instead of three. `Base64` reserves the `=` character as a padding character. This character is used once when the last group contains two bytes and twice when it contains one byte as illustrated by the two examples below. 434/10000 · 434
179 ../../protocols/ipv6.rst:633
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — The IPv6 subnet 15/10000 · 15
179 ../../protocols/wifi.rst:135
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — In addition to the data and control frames that we have briefly described above, 802.11 networks use several types of management frames. These management frames are used for various purposes. We briefly describe some of these frames below. A detailed discussion may be found in [IEEE802.11]_ and [Gast2002]_. 308/10000 · 308
179 ../../principles/linkstate.rst:60
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — LSP.Links[i].cost: cost of the link 35/10000 · 35
179 ../../protocols/tcp.rst:607
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — The second path is when the host has transmitted all data. Assume that the last transmitted sequence number is `z`. Then, the host sends a `FIN` segment with sequence number :math:`(z+1) \pmod{2^{32}}` and enters the `FIN_WAIT1` state. In this state, it can retransmit unacknowledged segments but cannot send new data segments. It waits for an acknowledgment of its `FIN` segment (i.e. sequence number :math:`(z+1) \pmod{2^{32}}`), but may receive a `FIN` segment sent by the remote host. In the first case, the TCP connection enters the `FIN\_WAIT2` state. In this state, new data segments from the remote host are still accepted until the reception of the `FIN` segment. The acknowledgment for this `FIN` segment is sent once all data received before the `FIN` segment have been delivered to the user and the connection enters the `TIME\_WAIT` state. In the second case, a `FIN` segment is received and the connection enters the `Closing` state once all data received from the remote host have been delivered to the user. In this state, no new data segments can be sent and the host waits for an acknowledgment of its `FIN` segment before entering the `TIME\_WAIT` state. 1174/10000 · 1174
180 ../../glossary.rst:196
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — telnet 6/10000 · 6
180 ../../principles/reliability.rst:938
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — Go-back-n : example 19/10000 · 19
180 ../../principles/linkstate.rst:62
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — These LSPs must be reliably distributed inside the network without using the router's routing table since these tables can only be computed once the LSPs have been received. The `Flooding` algorithm is used to efficiently distribute the LSPs of all routers. Each router that implements `flooding` maintains a `link state database` (LSDB) containing the most recent LSP sent by each router. When a router receives a LSP, it first verifies whether this LSP is already stored inside its LSDB. If so, the router has already distributed the LSP earlier and it does not need to forward it. Otherwise, the router forwards the LSP on all its links except the link over which the LSP was received. Flooding can be implemented by using the following pseudo-code. 752/10000 · 752
180 ../../principles/sharing.rst:1470
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — In general, the links have a non-zero delay. This is illustrated in the figure below where a delay has been added on the link between `R` and `C`. 146/10000 · 146
180 ../../protocols/email.rst:289
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — 0x14 4/10000 · 4
180 ../../protocols/ipv6.rst:635
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — Until now, we have focused our discussion on the utilization of IPv6 on point-to-point links. Although there are point-to-point links in the Internet, mainly between routers and sometimes hosts, most of the hosts are attached to datalink layer networks such as Ethernet LANs or WiFi networks. These datalink layer networks play an important role in today's Internet and have heavily influenced the design of the operation of IPv6. To understand IPv6 and ICMPv6 completely, we first need to correctly understand the key principles behind these datalink layer technologies. 571/10000 · 571
180 ../../protocols/wifi.rst:141
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — A first type of management frames are the `beacon` frames. These frames are broadcasted regularly by access points. Each `beacon frame` contains information about the capabilities of the access point (e.g. the supported 802.11 transmission rates) and a `Service Set Identity` (SSID). The SSID is a null-terminated ASCII string that can contain up to 32 characters. An access point may support several SSIDs and announce them in beacon frames. An access point may also choose to remain silent and not advertise beacon frames. In this case, WiFi stations may send `Probe request` frames to force the available access points to return a `Probe response` frame. 657/10000 · 657
180 ../../protocols/tcp.rst:609
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — The `TIME\_WAIT` state is different from the other states of the TCP FSM. A TCP entity enters this state after having sent the last `ACK` segment on a TCP connection. This segment indicates to the remote host that all the data that it has sent have been correctly received and that it can safely release the TCP connection and discard the corresponding :term:`TCB`. After having sent the last `ACK` segment, a TCP connection enters the `TIME\_WAIT` and remains in this state for :math:`2*MSL` seconds. During this period, the TCB of the connection is maintained. This ensures that the TCP entity that sent the last `ACK` maintains enough state to be able to retransmit this segment if this `ACK` segment is lost and the remote host retransmits its last `FIN` segment or another one. The delay of :math:`2*MSL` seconds ensures that any duplicate segments on the connection would be handled correctly without causing the transmission of an `RST` segment. Without the `TIME\_WAIT` state and the :math:`2*MSL` seconds delay, the connection release would not be graceful when the last `ACK` segment is lost. 1102/10000 · 1102
181 ../../glossary.rst:198
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — The telnet protocol is defined in :rfc:`854` 44/10000 · 44
181 ../../principles/reliability.rst:941
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — The main advantage of `go-back-n` is that it can be easily implemented, and it can also provide good performance when only a few frames are lost. However, when there are many losses, the performance of `go-back-n` quickly drops for two reasons : 245/10000 · 245
181 ../../principles/sharing.rst:1517
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — Footnotes 9/10000 · 9