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Table Of Contents  The TCP/IP Guide
 9  TCP/IP Application Layer Protocols, Services and Applications (OSI Layers 5, 6 and 7)
      9  TCP/IP Key Applications and Application Protocols
           9  TCP/IP File and Message Transfer Applications and Protocols (FTP, TFTP, Electronic Mail, USENET, HTTP/WWW, Gopher)
                9  TCP/IP General File Transfer Protocols (FTP and TFTP)
                     9  Trivial File Transfer Protocol (TFTP)

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TFTP Options and Option Negotiation
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345
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TCP/IP Electronic Mail System: Concepts and Protocols (RFC 822, MIME, SMTP, POP3, IMAP)
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TFTP Message Formats
(Page 2 of 5)

Read Request and Write Request Messages

These messages use a common message format, described in Table 235 and shown graphically in Figure 296.


Table 235: TFTP Read Request / Write Request Message Format

Field Name

Size (bytes)

Description

Opcode

2

Operation Code: Specifies the TFTP message type. A value of 1 indicates a Read Request message, while a value of 2 is a Write Request message.

Filename

Variable

Filename: The name of the file to be read or written.

Mode

Variable

Transfer Mode: The string “netascii” or “octet”, zero-terminated. (Why not just use one byte set to 0 for netascii and 1 for octet? Don't ask me! J)

Options

Variable

 



Figure 296: TFTP Read Request / Write Request Message Format

 


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