Planet XGS3-42000R User Manual page 85

management connection maintains until data trans fer is complet e. Then, using the address and port number
provided by the client, the server establishes data connection on port 20 (if not engaged) to transfer data; if
port 20 is engaged, the server automatically generates some other port number to establish data connection.
In passive connection, the client, through management connection, notify the server to establish a passive
connection. The s erver then creates its own data listening port and informs the client about the port, and the
client establishes data connection to the specified port.
As data connection is established through the specified address and port, there is a third party to provide data
connection service.
TFTP builds upon UDP, providing unreliable data stream transfer service wit h no user authentication or
permission-based file access authorization. It ensures correct data transmission by sending and
acknowledging mechanism and retransmission of time-out packets. The advantage of TFTP over FTP is that
it is a simple and low overhead file transfer service.
Chassis Switch can operate as either FTP/ TFTP client or server. When Chassis Switch operates as a
FTP/ TFTP client, configuration files or system files can be downloaded from the remote FTP/ TFTP servers
(can be hosts or ot her s witches) without affecting its normal operation. And file list can also be retrieved from
the server in ft p client mode. Of course, Chassis Switch can also upload current configuration files or system
files to the remote FTP/ TFTP servers (can be hosts or other switches). When Chassis Switch operates as a
FTP/ TFTP server, it can provide file upload and download service for aut horized FTP/ TFTP clients, as file list
service as FTP server.
Here are some terms frequently used in FTP/ TFTP.

ROM: Short for EPROM, eras able read-only memory. EPROM is repalced by FLASH memory in
Chassis Switch.

SDRAM: RAM memory in the Chassis Switch, used for system software operation and
configuration sequence storage.

FLASH: Flash memory used to save system file and configuration file.

System file: including system image file and boot file.

System image file: refers to the compressed file for Chassis Switch hardware driver and soft ware
support program, usually refer to as IMAGE upgrade file. In Chassis Switch, the system image file
is allowed to save in FLASH only. Chassis Switch mandates the name of system image file to be
uploaded via FTP in Global Mode to be nos.img, other IMAGE system files will be rejected.

Boot file: refers to the file initializes the Chassis Switch, also referred to as the ROM upgrade file
(Large size file can be compressed as IMAGE file). In Chassis Switch, the boot file is allowed to
save in ROM only. Chassis Switch mandates the name of the boot file to be boot.rom.

Configuration file: including start up configuration file and running configuration file. The
distinction bet ween start up configuration file and running configuration file c an facilitate the
backup and update of the configurations.

Start up configuration file: refers to the configuration sequence used in Chassis Switch start up.
Chassis Switch start up configuration file stores in FLASH only, corresponding to the so called
configuration save. To prevent illicit file upload and easier configuration, Chassis Switch mandates
the name of start up configuration file to be startup-c onfig.
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