Opakování ze školy :)

Obsah:

• jak vypadá handshake
• jak vypadá na síti DROP
• jak vypádá REJECT
• princip ACK

TCP primarily uses a cumulative acknowledgment scheme, where the receiver sends an acknowledgment signifying that the receiver has received all data preceding the acknowledged sequence number. The sender sets the sequence number field to the sequence number of the first payload byte in the segment's data field, and the receiver sends an acknowledgment specifying the sequence number of the next byte they expect to receive. For example, if a sending computer sends a packet containing four payload bytes with a sequence number field of 100, then the sequence numbers of the four payload bytes are 100, 101, 102 and 103. When this packet arrives at the receiving computer, it would send back an acknowledgment number of 104 since that is the sequence number of the next byte it expects to receive in the next packet.

• při komunikaci se nemusí potvrzovat každý paket…
• potvrzením ACK s číslem X říkám, že jsem dostal celou sekvenci až po X (byte) v pořádku
• množství odeslaných paketů bez potvrzení stanovuje „okno“