W7100A-64QFN WIZnet, W7100A-64QFN Datasheet - Page 122

• Manufacturer Part Number: W7100A-64QFN
• Description: 8-bit Microcontrollers - MCU 8051 CORE+HARDWIRED TCP/IP+MAC+PHY
• Manufacturer: WIZnet

Specifications of W7100A-64QFN

• Rohs: yes
• Interface Type: UART

© Copyright 2011 WIZnet Co., Inc. All rights reserved.
9.2.2
TCP protocol guarantees reliable data communication, but the UDP protocol use datagram
communication which has no guarantees of data communication. Because the UDP do not use
“connection SOCKET”, it can communicate with many other devices with the known host IP
address and port number. This is a great advantage; communication with many others by using
just one SOCKET, but also it has many problems such as loss of transmitted data, unwanted
data which received from others etc. In the UDP, to avoid these problems and guarantee the
reliability, the host retransmits damaged data or ignores the unwanted data which is received
from others. The UDP protocol supports unicast, broadcast, and multicast communication. It
follows the below communication flow.
9.2.2.1 Unicast & Broadcast
one time. On the other hand, the broadcast communication transmits data to all receivable
destinations by using ‘broadcast IP address (255.255.255.255)’. For example, suppose that the
user transmits data to destination A, B and C. The unicast communication transmits each
destication A, B and C at each time. At this time, the ARP
the destination hardware address of destinations A, B and C. User cannot transmit data to
destinations which have ARP
one time by using “255.255.255.255” IP address. At this time, there is no need to get the
The UDP is a Connection-less protocol. It communicates without “connection SOCKET”. The
The unicast is one method of UDP communication. It transmits data to one destination at
The broadcast communication can simultaneously transmit data to destination A, B and C at
UDP
TO
.
Figure 9.5 UDP Operation Flow
TO
can also occur when the user gets
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