fuse an attempt to open a connection; SYN bit is set to ONE to establish a connection; - FIN bit is set to ONE to a connection. Window: this field specifies the window size. The amount of data that the receiver of the segment is able to receive is mentioned in each segment. This field enables flow control to be performed. The receiver may respond with a zero-valued Window field. This indicates that its reception buffer is full. Checksum: this field is used to detect whether bit errors occurred during transfer. This check encompasses the header, the data encapsulated by the TCP header and a pseudo-header. The pseudo-header includes the source Wi-Fi Integration to the 4G Mobile Network and destination IP addresses, the Protocol field from the IP header and the length of the IP packet. Urgent Pointer: this field points to the first byte where urgent data can be found. It allows the sender to transmit information to the receiver without interrupting the message transmission in progress. Options: this field may be used for various functions: - maximum segment size (MSS): this information is only provided during the connection opening procedure. With an MTU of 1,500 bytes over Ethernet, the MSS is 1,460 bytes in IPv4 and 1,440 bytes in IPv6; - sizing of the reception buffer (Window Scale): the sender and receiver may negotiate a scale factor for the window size. This option makes it possible to circumvent the limitation in window size due to the 16-bit length of the Window field; - selective acknowledgment (SACK) instead of a bulk retransmission: the receiver may request retransmission of one or more specific segments. After obtaining them, it can then acknowledge all the buffered data. This option provides two pointers to indicate each received data block. 12.2.2. Opening and closing a connection Opening a connection involves the following three steps: - the client sends a segment having a SYN bit set to ONE and an ACK bit set to ZERO. The client indicates the sequence number X; - the server responds with the SYN bit 