The actual speed of your network connection can vary depending on several different things. The wireless router that you are connecting to is obviously a 54Mbps router. This means that data transfered from the router to the client systems in theory go at a max of 54Mbps. (although this rarely actually happens)
The speeds you see on WinSCP can vary depending on if the server you are connecting to is within the same network as your router (ie. within you home) or if they are located outside your local network and you are accessing them over the internet.
If you are accessing a server within your house then you should be getting much faster transfer rates. This of course depends on the connection speed of both the server and your laptop. If the server has a much older or slower wireless or wired network card then you will not reach anything near 54Mbps. (it will be limited to the slowest device)
If you are using winscp to access a remote server then your transfer speed will be limited to the network connection you are using. I'm in Canada so i know that the basic internet connection provided by someone like Bell Aliant will be around 1.5Mbps. So therefore you can only download to that maximum even though your local network runs at 54. Since you are only getting around 100-120 kb/s then i would assume you are accessing a remote server.
The only way to speed this up is to pay out for a faster net connection.
So the things you need to know are:
- What is the connection speed on both ends (server and client)
- What speed is your internet connection.
- How much other traffic is going over your local network (could cause a saturation of your home network if others are transferring large files.)
- Ensure that the drivers/firmware for both client and server network devices are up to date.
Hope this helps