Page 179 - Computer_Science_F5

Computer Science In Figure 3.24, the sending the recipient identify the correct order of
machine sends segments 1, 2,
segments. Upon receiving the data, the recipient
and 3 to the receiving node. The
examines the sequence numbers to reassemble
receiving node confirms successful
the original message accurately. If segments
receipt by requesting segment 4.
arrive out of order, the recipient holds them
FOR ONLINE READING ONLY
After getting this acknowledgment,
the sender transmits segments until all necessary segments are received, then
arranges them based on their sequence numbers.
4, 5, and 6. If segment 5 does
not arrive, the receiving node Sequencing is vital in applications like video
requests a retransmission of that streaming, voice communication, or file transfer,
segment. The sender resends the where maintaining data integrity and order is
missing segment and waits for an critical. By ensuring data is transmitted and
acknowledgment before sending received in the correct sequence, connection-
segment 7. oriented services provide accurate and reliable

In essence, this process ensures information delivery.
the reliable, sequential delivery
of messages in a network. It uses
error recovery and flow control
mechanisms to manage end-to-
end message delivery and supports
both connection-oriented and
connectionless packet delivery.

Sequencing
Sequencing is crucial in connection-
oriented services as it ensures data
is transmitted and received in a
specific order, preserving the exact
sequence sent by the sender. This
guarantees the recipient receives
data accurately as intended, which
is essential for time-sensitive or
sequence-dependent information.

To achieve sequencing, each
data segment is assigned a
unique sequence number before
transmission. This number helps Figure 3.25: Sequencing in network

170
for Advanced Secondary Schools

Computer Science Form 5.indd 170 23/07/2024 12:33