How to use Simple File Transfer (SFT)

User Guide v0.2

This user guide will help you understand how to use SFT.

In order to connect to a network, each computer must have an address and it called Internet Protocol address (IP address).

There are many versions of IP address but most popular are IPv4 and IPv6.

An IP address version 4 should be like or or etc

An IP address version 6 should be like 2402:800:63aa:fc75:a006:aadb:4f78:b75c or 2402:800:63aa:fc75:446d:678c:b01a:deed or etc

For more information, you can read here IP address - Wikipedia



"If we think of an IP address as a telephone number, (an identifying number that allows communication between two locations), then we can think of ports as telephone number extensions"

"Ports are like telephone number extensions as they allow multiple pieces of data to flow back and forth on a single IP address. In fact, port numbers are appended to the end of IP addresses just as extensions are appended to telephone numbers."

"In other words, ports are numerical identifiers that make it possible for you to check your email and browse the web at the same time. Technically speaking, this is possible because browsing the web traffic generally uses port 80, and getting your email generally uses port 110."

Common Ports
FTP: 21
SSH: 22
Telnet: 23
SMTP: 25
DNS: 53
HTTP: 80
POP3: 110

Other Applications
Remote Desktop: 3389
PC Anywhere: 5631

SFT ports: 10296, 8888 and 5126

For more information, you can read here What is a Port? (

To use SFT, you must know your parner's IP address.

SFT will provide all IP addresses of your computer upon opening. You can copy and send it to your partner.

Because IPv4 is limited, there's no way it's enough for all people around the world. People created NAT which shares public IP to many devices in a network.

Your Router (public IP) <-> NAT <-> Your computer (local IP)


See the source image

It's simple, IPv4 uses 32-bit addresses which is limited to 4.294.967.296 addresses. So, people created NAT and that's why we have public IP and local IP (private IP) now.

Private IP Address and Public IP Address are used to uniquely identify a machine on the internet. Private IP address is used with a local network and public IP address is used outside the network. Public IP address is provided by ISP, Internet Service Provider.

Your Router (public IP) <-> NAT <-> Your computer (local IP)


More info at Difference between Private and Public IP addresses (

If you and your partner are in a same network like cafe, home,... you should use local IP, either IPv4 or IPv6.

i.e Your laptop local IP is, your friend's local IP is

If you want to send files over the internet, you must use public IP (must configure port forwarding or UPnP or and pubic IPv6)

Which IP version I should use?

IPv6 is recommended if it's available

No, if you use IPv4 without port forwarding or UPnP.

When you use a public IPv4 to send, your partner's router would not understand the request so it would reject.

If both of computers have IPv6, please use it.

If not, please continue reading to know how to configure port forwarding or UPnP.

How to configure port forwarding?

Open browser and enter or or anything which bases on your local network

Click Advanced 

Click Continue.

Base on your router, username and password are usually:

admin/serial number under router

Find UPnP or Port Forwarding

If you have UPnP, click and enable it

When you open SFT, it should show like this

If you don't have UPnP, click Port Forwarding and add:

Remember to change LAN Host IP address to your computer's IP.

After you configure, open SFT and go to and check port 10296, 8888 and 5126.

If those ports still couldn't be seen, it might because your ISP is blocking. Contact them for help.

How to transfer files?

Plese watch demo here








SFT is updated automatically via SFT Updater. If a new version is available, SFT will notify you to download and update.

If any error, you can manually open SFT Updater to update SFT.


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