Transferring Files and Folders 

T

WEAK THE RECEIVE AND SEND BUFFERS

Setting these buffers allow you to fine tune transfers over high latency or lossy connections 

like those over satellite links or with l egacy CDMA wireless connections. It is unlikely you 

will ever need to adjust this setting, but if you have problems with successful transfers and 

suspect the latency or quality of the connection is at fault, try tweaking these buffers. 

The receive buffer holds data until CuteFTP is ready to read it; the send buffer holds dat  

a

until it can be sent to the server. Typically, both send and receive buffe s

r  should be set to the 

same size. The default is set at 65536 bytes, the normal maximum window size of TCP.  

You can measure the latency and estimat  

e the available bandwidth with network monitoring 

tools. There is some guesswork involved, as most tools are not entirely accurate, but they 

can guide you to finding a sweet spot where transmissions are successful. If you have a lossy 

connection, try lowering the buffer size. If you have high latency, a higher buffer size might 

help. 

Normally, the optimal buffer size is your ba d

n width times the latency of the link. So,  

bandwidth (in bits) * latency (round trip time in 

seconds) = socket buffer size (in bits) 

Convert bits to bytes (bits/8=bytes) for the buffer size. 

So, if your ba

s and yo

ndwidth is 1,536,000 bp

u have a latency of 200ms (.2 seconds), your 

socket buffers should be set to 38400: 

1536000*.2=307200 bits 

307200/8=38,400 bytes 

You can also try halving or doubling the buffer size. For example, if the buff r

e  is set to 

65536 (64kb), try 32768 (32kb). 

T

URN OFF TIME STAMP IN LOGS

When this feature is on, CuteFTP adds a time stamp next to each log event. This option 

does consume system resources, and if perform n

a ce is critical, you can turn this off. For 

more information, see Record/Display time stamps in Log file settings

T

RY USING 

MULTI PART TRANSFERS

If you are transferring large files, try using a multi part transfer. You can only use this option 

if the server you are connecting to supports it. 

C

HECK THE GLOBAL BANDWIDTH LIMIT

Check to see if the global bandwidth limit is limiting you  

r throughput. This setting in Global 

Options throttles the bandwidth of all se s

s ions on CuteFTP. See Global bandwidth limits in 

Transfer Settings. 

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