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172 ../../protocols/wifi.rst:107
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — When a frame is sent from a WiFi device to a server attached to the same LAN as the access point, the first address of the frame is set to the MAC address of the access point, the second address is set to the MAC address of the source WiFi device and the third address is the address of the final destination on the LAN. When the server replies, it sends an Ethernet frame whose source address is its MAC address and the destination address is the MAC address of the WiFi device. This frame is captured by the access point that converts the Ethernet header into an 802.11 frame header. The 802.11 frame sent by the access point contains three addresses : the first address is the MAC address of the destination WiFi device, the second address is the MAC address of the access point and the third address the MAC address of the server that sent the frame. 854/10000 · 854
172 ../../protocols/tcp.rst:559
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — by extension, some implementations send an `RST` segment when they need to close an existing TCP connection (e.g., because there are not enough resources to support this connection or because the remote host is considered to be unreachable). Measurements have shown that this usage of TCP `RST` is widespread [AW05]_ 316/10000 · 316
173 ../../glossary.rst:110
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — The SYN cookies is a technique used to compute the initial sequence number (ISN) 80/10000 · 80
173 ../../principles/reliability.rst:846
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — Unfortunately, frame losses do not disappear because a reliable protocol uses a sliding window. To recover from losses, a sliding window protocol must define : 159/10000 · 159
173 ../../principles/linkstate.rst:52
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — Once a router has discovered its neighbors, it must reliably distribute all its outgoing edges to all routers in the network to allow them to compute their local view of the network topology. For this, each router builds a `link-state packet` (LSP) containing the following information: 286/10000 · 286
173 ../../protocols/email.rst:272
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — 00010100 11111011 10011100 00000011 11011001 01111110 55/10000 · 55
173 ../../protocols/ipv6.rst:576
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — When a TCP segment is transported in an IP packet that is fragmented in the network, the loss of a single fragment forces TCP to retransmit the entire segment (and thus all the fragments). If TCP was able to send only packets that do not require fragmentation in the network, it could retransmit only the information that was lost in the network. In addition, IP reassembly causes several challenges at high speed as discussed in :rfc:`4963`. Using IP fragmentation to allow UDP applications to exchange large messages raises several security issues [KPS2003]_. 561/10000 · 561
173 ../../protocols/wifi.rst:109
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — 802.11 control frames are simpler than data frames. They contain a `Frame Control`, a `Duration` field and one or two addresses. The acknowledgment frames are very small. They only contain the address of the destination of the acknowledgment. There is no source address and no `Sequence Control` field in the acknowledgment frames. This is because the acknowledgment frame can easily be associated to the previous frame that it acknowledges. Indeed, each unicast data frame contains a `Duration` field that is used to reserve the transmission channel to ensure that no collision will affect the acknowledgment frame. The `Sequence Control` field is mainly used by the receiver to remove duplicate frames. Duplicate frames are detected as follows. Each data frame contains a 12 bits sequence number in the `Sequence Control` field and the `Frame Control` field contains the `Retry` bit flag that is set when a frame is transmitted. Each 802.11 receiver stores the most recent sequence number received from each source address in frames whose `Retry` bit is reset. Upon reception of a frame with the `Retry` bit set, the receiver verifies its sequence number to determine whether it is a duplicated frame or not. 1211/10000 · 1211
173 ../../protocols/tcp.rst:561
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — When an `RST` segment is sent by a TCP entity, it should contain the current value of the `sequence number` for the connection (or 0 if it does not belong to any existing connection) and the `acknowledgment number` should be set to the next expected in-sequence `sequence number` on this connection. 299/10000 · 299
173 ../../principles/sharing.rst:1226
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — From the above example, we can adjust the transmission rate by adjusting the sending window of a reliable transport protocol. A reliable transport protocol cannot send data faster than :math:`\frac{window}{rtt}` segments per second where :math:`window` is the current sending window. To control the transmission rate, we introduce a `congestion window`. This congestion window limits the sending window. At any time, the sending window is restricted to :math:`\min(swin,cwin)`, where `swin` is the sending window and `cwin` the current `congestion window`. Of course, the window is further constrained by the receive window advertised by the remote peer. With the utilization of a congestion window, a simple reliable transport protocol that uses fixed size segments could implement `AIMD` as follows. 801/10000 · 801
174 ../../glossary.rst:111
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — TCB 3/10000 · 3
174 ../../principles/reliability.rst:848
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — a heuristic to detect frame losses 34/10000 · 34
174 ../../principles/linkstate.rst:54
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — LSP.Router: identification (address) of the sender of the LSP 61/10000 · 61
174 ../../protocols/email.rst:274 • ../../protocols/email.rst:293 • ../../protocols/email.rst:307
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — 6-bit 5/10000 · 5
174 ../../protocols/ipv6.rst:578
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — ICMPv6 is used by TCP implementations to discover the largest MTU size that is allowed to reach a destination host without causing network fragmentation. A TCP implementation parses the `Packets Too Big` ICMP messages that it receives. These ICMP messages contain the MTU of the router's outgoing link in their `Data` field. Upon reception of such an ICMP message, the source TCP implementation adjusts its Maximum Segment Size (MSS) so that the packets containing the segments that it sends can be forwarded by this router without requiring fragmentation. 556/10000 · 556
174 ../../protocols/wifi.rst:115
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — IEEE 802.11 ACK and CTS frames 30/10000 · 30
174 ../../protocols/tcp.rst:563
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — TCP `RST` wars 14/10000 · 14
174 ../../principles/sharing.rst:1228
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — For the `Additive Increase` part our simple protocol would simply increase its `congestion window` by one segment every round-trip-time. The `Multiplicative Decrease` part of `AIMD` could be implemented by halving the congestion window when congestion is detected. For simplicity, we assume that congestion is detected thanks to a binary feedback and that no segments are lost. We will discuss in more details how losses affect a real transport protocol like TCP in later sections. 481/10000 · 481
175 ../../glossary.rst:113
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — The Transmission Control Block is the set of variables that are maintained for each established TCP connection by a TCP implementation. 135/10000 · 135
175 ../../principles/reliability.rst:849
	English ↹ ↵ NBS … “ ” ‘ ’ ﹙-﹚ ‐ – — a `retransmission strategy` to retransmit the lost frames 57/10000 · 57