W5100E01-AVR WIZnet, W5100E01-AVR Datasheet - Page 99

• Manufacturer Part Number: W5100E01-AVR
• Description: Development Boards & Kits - AVR W5100 EVAL BOARD BASED ON AVR
• Manufacturer: WIZnet

Specifications of W5100E01-AVR

• Rohs: yes
• Product: Development Boards
• Tool Is For Evaluation Of: ATMEGA128
• Core: AVR8
• Interface Type: LAN, RS-232
• Operating Supply Voltage: 5 V
• Data Bus Width: 8 bit

parse_name() processes QNAME Field of Question Section or NAME, RDDATA Field of RRs Section.
QNAME, NAME, RDDATA Field are mostly composed as in <Fig 3.41: Example of QNAME Field
transformation of Question Section >. However, it can be compressed to reduce DNS Message Size.
Compression scheme is expressed in 2 Byte. If the first byte - the upper 2 bits are ’11,’ it means the Label is
ST
nd
compressed. It has the offset that is composed of 1
Byte excluding upper 2 bits and 2
Byte
This offset is Offset of DNS Message and means the actual value of Label is located by the offset from the
starting point of DNS message. When Compress Scheme tries to reuse Domain Name that was already
used in DNS Message, relevant Domain Name sets the offset that is located in DNS Message as Indirect so
that it can reduce the size of DNS Message. <Fig 3.45> is an example of Compress Scheme of DNS
Message and its application.
<Fig 3.45: DNS Message Compression Scheme>
The example of Compression Scheme of <Fig 3.45> shows DNS Message in case of “F.ISI.ARPA”,
“FOO.F.ISI.ARPA”, “ARPA”, and ROOT. “F.ISI.ARPA” is processed in the format of <Fig 3.41: Example of
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