TCP/IP Configuration and Management Manual

NonStop TCP/IP Processes and Protocols
TCP/IP Configuration and Management Manual—427132-004
B-26
Trivial File Transfer Protocol (TFTP)
The SNAP driver also is responsible for distributing incoming packets to the IP and
ARP software. Incoming packets are delivered to the SNAP driver from SLSA in the
form of AGSDUs. The SNAP driver separates the individual messages and strips off
unnecessary protocol headers before delivering messages to the IP and ARP input
routines.
For more detailed technical information on the SNAP, refer to RFC 1042 (available on
the Internet at: http://ds.internic.net/ds/rfc-index.html.)
Trivial File Transfer Protocol (TFTP)
The Trivial File Transfer Protocol (TFTP, IEN 113) client and server programs run over
a UDP socket. The TFTP programs are not connection-oriented, and can be used only
to retrieve or store publicly readable and writable files. The TFTP server listens for
requests on the TFTP port (UDP port 69). More than one file can be transferred
simultaneously.
The TFTP is divided into client and server programs, like other Internet applications.
These two programs enable you to retrieve a file from or store a file on a remote
Figure B-15. Subnetwork Access Protocol (SNAP) Interface
034VST .vSD
Sockets
TCP/IP
SNAP Driver
TCP/IP
Network
SNAP filter
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driver/interupt handler
Application
Programs
LAN
Manager
(LANMAN)
TCP/IP Subsystem
SLSA Subsystem
SPI-formatted
Messages
SCF
SCP
DSM
Management
Application
SCF Commands
and Responses
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