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Step-by-Step Guide to Eliminating Slow FTP Speeds (2020 Update)

FTP is a very common method of transferring files from a remote machine to your local desktop.

Your file transfer experience is ideal when FTP speeds are maximized but that’s not always the case…

Your first instinct for improved bandwidth might be to pay for it but there is more to speed than just your Internet bandwidth.

Testing, tweaking and testing again might be one of the best ways to optimize your resources for FTP speeds.

In this step-by-step guide to eliminating slow FTP speeds, we’ll provide detailed information so that you can troubleshoot your problem and find ways to optimize your resources for speed and performance.

Step-by-step guide to eliminate Slow FTP Speeds.

Table Of Contents

  1. Understanding the Speed Limitations and Testing Them.
    1. FTP speed metrics: Mbps vs MBps vs KiB/s.
    2. Get Familiar With your Network.
    3. Find your Actual Bandwidth.
    4. The Online FTP Tester.
    5. Your FTP speed depends on the path and the destination.
  2. FTP Mechanism and Protocols.
    1. So, How Does FTP work?
    2. Alternatives to FTP.
    3. File Transfer Mechanisms Speeds Comparison.
  3. Optimizing your FTP Client for Maximum Speed.
    1. Concurrent Downloads
    2. Segmented Downloads.
    3. Other Features that can improve FTP speed.
    4. How to Speed up FileZilla Transfers?
    5. How to Speed up CuteFTP Transfers?
  4. A step-by-step guide to troubleshooting your slow FTP speed.
    1. The first test you can do is to perform local FTP speeds.
    2. Let’s Verify the Network.
    3. Use Wired Instead of Wireless.
    4. Now Let’s Check the Local Router.
    5. Check Whether you are connected to a VPN or Proxy.
    6. Testing other file transfer protocols and clients.
    7. Check your Antivirus
    8. Check the Firewall.
    9. Look for Other Apps that might be Hurting your Performance.


1. Understanding the Speed Limitations and Testing Them. 

Knowing what to expect from your bandwidth is key to optimizing your FTP download speed.

But have you asked yourself… Do you even need to optimize FTP speeds? 

When your resources are giving the most, and maybe the slow problem is coming from the other end-point “the server”, or somewhere in between where you don’t have much control.

First, get to know what you already have in your hands. Knowing what speed to expect gives you more control and patience when transferring files. So, don’t rush to go out and buy more bandwidth or a more powerful computer.

Let’s understand our speed limitations and test them. 

1.1 FTP speed metrics: Mbps vs MBps vs KiB/s.

You might have bought a specific bandwidth from your local ISP, but you are getting a different reading on the average FTP download speed statistics. Why is this possible? 

First, let’s get the Mbps, MBps, MB/s, KiB/s metrics confusion out of the way. 

Let’s take, for example, the Home Internet Plan from Verizon

Below is a chart of the advertised Fios (Fiber-optics) speed. As you can see, all of their speeds are shown in Mbps (Megabits per second), and this is the same metric used by many other ISPs. 100/100 Mbps means 100 Mbps download and 100 Mbps upload speed (symmetrical connection).

Verizon 100/100 Mbps.

Bear in mind that most Internet plans provide asymmetrical connections, which are when upload speeds are not the same as download speeds. Usually, home Internet plans come with higher download speeds, and their advertisements show only the faster speed. 

So most of the time, what happens is that you expect 100% of that advertised Mbps download or upload speeds. The Internet speed, in the case of 100/100 Mbps, is not the same as the actual download/browsing speed (throughput). The throughput or download speed is the actual rate at which you are receiving/sending data from/to the Internet. When determining real speeds, many factors must be considered. 

So when you are downloading content from the Internet, the browsers, FTP clients, P2P platforms, all show you different speed metrics. 

Download speeds in Chrome.

So what are the common bandwidth measurements given by FTP clients? 

For example, FileZilla gives the transfer rates using KiB/s (Kibibit per sec), which is not KB/s, as Google Chrome does. 

Bandwidth metrics in Filezilla.

The following conversion table will help you briefly understand the differences in magnitude with popular metrics. 

We will use 1 Mbps (Megabits per second) as the base unit. 

  • One Mbps = 1000 Kbps (Kilobits per second). 
  • 1 Mbps = 125 KB/s (Kilobytes per second).
  • One Mbps = 976.5 KiB/s (Kibibites per second). 
  • 1 Mbps = 122.07 KiB/s (Kibibytes per second). 
  • One Mbps = 0.953674 Mib/s (Mebibites per second).
  • 1 Mbps = 0.125 MB/s (Megabytes per second).

1.2 Get Familiar With Your Network. 

To increase FTP speed, start by getting to know your resources, which might include your machine, the network throughput, ISP bandwidth, and the FTP server. In the end, all those network resources will shape the FTP download speeds. 

Your computer.

A low CPU and memory computer can be giving you a bad experience. Having the most powerful computer in the world doesn’t change things if bandwidth (the pipe) is limited, but it can improve the experience. Typically, 2GB of RAM will be enough for web browsing. But a higher RAM (4GB, for example) and a better higher resolution graphic board will guarantee smooth web browsing, streaming, and downloading. SSD storage is also crucial to improve FTP downloads.

To take full advantage of your high-speed bandwidth, access it with the right equipment. It is obvious that you feel slow FTP transfer rates; if you are using an old computer to connect to the Internet through a high-speed fiber connection.

Services and Apps.

Some services and applications running on your network are eating away your bandwidth.  Your computer resources might be powerful and healthy but maybe you are demanding too much of them. Other bandwidth-consuming services, such as streaming, P2P, video conferencing, etc., will affect your speed and the speed of the entire LAN.

Traffic

Too many devices connected and traffic in your local network can be causing a delay.  No matter how fast your bandwidth is, if there are many devices connected to the same network, the speed will be slow. Each device connected to the Internet router/gateway will take a bite of the bandwidth. It is like having a super 5-lane highway but congested with tons of vehicles. Try connecting to a dedicated network.

Know the transmission media.

Your LAN might be connected via WiFi or Ethernet (Cat5 or Cat 6). If you have an Ethernet wire connected to the Internet gateway, your speed will likely be faster than WiFi. In the same case, the ISP access links can vary from Cable, ISDN, ADSL, ADSL+2, Fiber Optics, T1, WiFi, Broadband, Satellite, etc. Of course, a satellite like will be 10x slower than a dedicated T1 or fiber optics. 

1.3 Find your Actual Bandwidth. 

Most ISPs advertise their Internet download speeds in Mbps. While it is technically correct, it confuses many consumers, because their testing tools display other metrics.

Some ISPs also advertise only their asymmetrical speeds. They show how incredible their download speeds are but don’t mention the upload speeds, which sometimes are 3x slower. 

To know your real bandwidth, measure it using online testing tools. 

Today there are many HTML5 Internet bandwidth analysis and testing tools, such as SpeedTest.net, speedof.me, fast.com, etc. Fortunately, most of these tools are free and run through the web browser. Avoid using Java or Flash-based speed test services, as they are not so precise as the HTML5 tools. 

Using SpeedTest. 

  1. To get more accuracy, connect directly to the Internet gateway using a Cat5 or Cat6 Ethernet cable. Avoid Wifi. Also, restart your computer and router before testing to get a more precise test.
  2. Bear in mind that there will be local network congestion and possible bandwidth throttling from your local ISP. Before running the test, stop anything that is putting a tax on the Internet connection, such as streaming or P2P. 
  3. One of the most popular bandwidth testing tools is SpeedTest by Ookla. This online test gives you an average download/upload speed and ping times.
  4. To avoid any confusion, you can change the speed metrics from Mbps to Kbps (or vice-versa).
Change Mbps to Kbps in Speedtest.

The test is free, so run it as much as you need. In fact, it is a good idea to run it at different times, and with different devices such as a mobile, tablet, desktops, etc.

If your speed result is less than what it should be, try restarting your devices, including the router. If the bandwidth is still slow and not what you are paying for, contact your ISP.

Speedtest FTP speed.

Speed testers such as Ookla’s SpeedTest work using HTML5 and a large network of geographically distributed servers (more than 1000). The client connects to a server, sends a ping and measures the round trip time.  

Does an HTML5 speed test provide the same results as it would for an FTP speed? 

These tools operate over TCP with an HTTP fallback. The client measures the ping round trip time in milliseconds and then performs a download speed test. 

It establishes multiple connections to the server over port 8080 and then downloads a small piece of data. As time goes by, the test increases the file size and buffer, to stress-test the connection.

Whatever protocol you use to establish a connection, its overhead will slightly affect the speed of the network; fortunately, HTML5 tests use TCP, which is the same transport protocol used by FTP.

1.4 The Online FTP Tester

If you don’t have a server to test transfer rates, you can use a free online FTP server. A popular and reliable FTP online tester is, Tele2Speedtest

You can find out about your maximum upstream and downstream speed without having a username and password. Note: when you upload a file, their service removes it immediately (but never upload sensitive information). You can also login anonymously from any FTP client.

Online FTP test.

Their service allows you to test your FTP using different methods. Test your upload/download transfer rates with a variety of test-files via HTTP or FTP. Their FTP speed test server is secure and fast. It maintains a high-throughput of close to 10Gbps.

You can log using any FTP client, without any username/password and test FTP upload and download speeds. 

Free FTP Server.

1.5 Your FTP Speed Depends on The Path and The Destination.

The path and its destination (FTP Server) might also limit your FTP transfer speed. If the FTP server is located across the world, there will definitely be a delay. Also, if the server is shared with other users and its speed is limited, you will likely notice slower speeds. The FTP speed can also be affected by its path and its heavy traffic.  

Know the FTP Server and its Path.  

  • Understand the geographical distance between the FTP client and server. Geographical distance plays an important factor in Server/Client applications such as FTP. If the FTP server sits on the same physical network, the download delays will be minimal. But if the server sits on the other side of the world, the download delays will increase dramatically. 

    Unless you move next door to the FTP server, there is not much you can do here. But knowing the physical distance will help you understand the added time delay you should expect.
  • Is the FTP server dedicated or shared? With a dedicated FTP server, you can enjoy the highest speed and performance possible. But if you share it with other users, a slice of speed and capacity will be restricted and allocated to each user. A shared FTP server might have a maximum rate per connection, thus limited speed. 

    To avoid waiting for speed, RapidSeedbox offers affordable, fast, and reliable dedicated and unlimited servers. We do not limit FTP speeds from the server to the client. 
  • Is the FTP Server limited? The FTP server you are downloading/uploading might be limiting the FTP speeds. An example is web hosting services such as Godaddy, which has a reputation for limiting the speed of FTP servers. They usually lower the internal transfer buffer size and socket buffer size values.

    Find out and make sure that the FTP server is not limiting upload/download speed. 

Consider Daytime Congestions. 

If you are trying to download something from the Internet from 6:00 PM to 11:00 PM, you will likely hit Internet rush hour. Thousands of other users at your local network or ISP might be using P2P, watching streaming TV, or playing video games. 

The following graph can provide a better picture. According to Sandvine, a leader in Internet phenomena, there was a significant change in Netflix’s bandwidth (red vs. blue lines) after a release of House of Cards (on the weekend). The following picture shows how the bandwidth was saturated during peak hours while it decreased dramatically around 2:00 AM.

Internet Congestion.

Although your ISP should be capable of reserving and accommodating the bandwidth that you bought for applications such as streaming, their entire network infrastructure will suffer from daytime congestions and unexpected events (such as the House of Cards launch).

If you are a big-time FTP user, avoid rush hour. The hours between 2:00 AM to 10:00 AM have the lowest local traffic to roam around the Internet. 


2. FTP Mechanism and Protocols. 

FTP (File Transfer Protocol) is one of the oldest methods for transferring computer files. It is commonly used for uploading/downloading web pages to web hosting services, download content from the Internet, as a file-sharing system in enterprises, and more. 

In some cases, FTP is critical for some application functionalities. It plays one of the most important roles in a Seedbox or VPS. A good file transfer speed will guarantee good user experience. FTP is often the preferred method for downloading content from a remote server to a local client. This is because the FTP port is not blocked, or its traffic is not throttled by the ISP. 

2.1 So How Does FTP Work? 

FTP works as a client/server application. As long as both have a connection, they can transfer files with each other. FTP uses the TCP/IP (Transmission Control Protocol/Internet Protocol) communication model to transfer data from server to client regardless of its location.

FTP uses port 21 and does not provide any encryption mechanisms, which means that it sends all information in plain clear text, including passwords. 

The FTP Client provides: 

  • Login credentials.
  • FTP commands. 
  • And browse directory

The FTP Server provides: 

  • Authentication.
  • Directory display
  • Port assignment. 

To illustrate, the FTP functionality, let’s go with a popular application: A Seedbox/VPS

  1. A seedbox provider gives credentials and IP to access a remote seedbox (with an FTP Server) from your computer (FTP Client). 
  2. You log in remotely from your computer.
  3. From the seedbox, you can download and store media content. The FTP server in your seedbox provides the authentication, displays directory and assigns ports (21, 22, etc)
  4. Connect from your computer using an FTP client to your FTP server in your seedbox. The FTP client takes login credentials, allows you to send FTP commands, and browses through the FTP server directory. 
FTP in a Seedbox.

2.2 Alternatives to FTP.

There is also FTPS (FTP Secure or FTP-SSL), which is standard FTP with added security thorough TLS/SSL encryption mechanisms. Another common method is SFTP (SSH File Transfer Protocol,) which works via SSH protocol and provides more robust security. And even HTTP (HTTPS) is often used as an alternative to FTP. 

File transmission protocols are defined at the FTP server. The client will have to adapt to these conditions. 

2.3 File Transfer Mechanisms Speeds Comparison. 

Although FTP is still around, it is not recommended due to security reasons. FTP by itself can be very insecure because it sends passwords in plain text. But FTP is still used in LANs or isolated networks. 

Because of this lack of encryption and low overhead, FTP is slightly faster than other protocols. 

But speed is not the most crucial factor that differentiates FTP, SFTP, FTPS, and HTTP. You might be more limited by the speed of your network than by the overhead of these protocols.

In the following section, we will provide a brief comparison of the speed of popular transfer mechanisms, FTPS, SFTP, and HTTP. 

FTPS vs. SFTP.

Even FileZilla will warn you, FTP by itself has no encryption whatsoever and is insecure. Other transmission mechanisms are recommended over plain FTP. Choose either FTPS or SFTP (as defined by the server).

Configure FTP in FileZilla

FTP/SSL (FTPS) is an extension of FTP which adds support for SSL/TLS encryption. It is becoming the norm to use FTPS instead of traditional FTP.

SSH Transfer Protocol (SFTP) is not related to FTP and works very differently. SFTP uses a fixed window size that can limit speed. SFTP also requires only one port 22 to establish a connection, so it is friendlier to firewalls.

  • The main difference between the two methods (FTPS and SFTP) is functionality. There is a lot more overhead going on in FTPS since it needs multiple ports. Every time a new transfer file is requested, FTPS needs a new port for the data channel. The positive side of this is that the control and data channels run asynchronously in two different connections; this isolation in the data channel makes transfers much faster. 
  • On the other hand, SFTP needs one port number for all communication, making it easier to secure and with less overhead. But having the same channel for control and data can turn out to be a bit slower. 
  • FTPS is a more appropriate protocol for masses or a broader public, while SFTP is commonly used for a limited number of users. 

FTP servers at RapidSeedbox support both protocols. Check this guide to learn how to log into your Seedbox using SFTP. Check the following guide for more information on how to log in to your Seedbox with explicit FTPS

FTPS vs HTTP (and WebDAV).

What are the main speed differences between HTTP-based WebDAV and FTPS? Both protocols serve the same purpose but are very distinct in functionality and speed.

Web-based Distributed Authority and Versioning (WebDAV) is an extension to HTTP. WebDAV allows users to manage files on a remote web server. Since it is HTTP-based, it doesn’t need more firewall ports to be open, other than the common port 80. 

FTP client tools such as CyberDuck support WebDAV.

WebDAV vs FTP.
  • WebDAV pipelines many transfers over one TCP connection (one socket for control/data). It doesn’t need to create many channels when downloading many files, as FTPS does. This TCP connection can be persistent, so WebDAV can provide faster rates than FTP when transferring many small files. There is no need to create a channel for each file, so the overhead is a lot lower.
  • WebDAV has many advantages over FTPS, including firewall-bypassing, GZIP compression, authentication with NTLM or Kerberos, and features such as partial downloads, locking, and remote file editing. 
  • For a single file transfer, the speed of WebDAV and FTP should be roughly the same. Both protocols transfer a file over a TCP socket, but when there are many small files to transfer, WebDAV can turn out to be much faster. 

Other File Transfer Mechanisms. 

  • FTP vs SCP. SCP (Secure Copy Protocol) uses SSH (similar to SFTP). This protocol is designed for a one-time transfer between client/server on the network. SCP does not have the ability to list folder contents, manage files, etc, as SFTP does. Its only mission is to move data. When it comes to speed, SCP is similar to SFTP, and generally a bit slower than FTP (FTPS). 
  • FTP vs Rsync. Rsync is a computer application used for transferring and synchronizing files between a computer and an external hard drive or a server across the network. It compares modification times and size of files and copies (or removes) what’s necessary. Rsync compresses data with GZIP, and when possible, it only sends delta copies to minimize network usage. Rsync is hands down, much faster if there is a portion of the file on the destination. But it is similar to FTPS is the transfer starts from zero. 
  • FTP vs P2P: Peer 2 Peer (P2P) is entirely different than FTP. First of all, P2P does work on the client/server model; it uses a serverless network. The P2P application uses a distributed architecture that divides workloads between peers. P2P has tons of advantages over FTP in terms of functionality and speed, but it is not widely accepted because of the use of torrents. A popular P2P file synchronization tool is Resilio Sync (BTSSync).

3. Optimizing your FTP Client for Maximum Speed. 

So now that you understand your network limitations and the different transferring mechanisms.

How can you speed up the FTP download speed?

Most of the FTP configuration and limitations takes place over the FTP server. Yet there are still some client optimizations that may improve your speed.

Let’s start with a few settings and features found in popular FTP clients that can help improve speed: The most popular are Concurrent downloads and Segmented downloads. These features are usually only available for FTP and are something not found in HTML. 

3.1 Concurrent Downloads.

Also known as multi-thread downloads. With this feature, you can download multiple files from multiple remote servers at the same time via simultaneous connections. 

FTP servers limit each session to maximum download speed. To optimize FTP speed on the client-side, increase the parallel (concurrent downloads) or adjust the “maximum simultaneous transfers.” This feature will bypass some limitations defined by the server.

Concurrent downloads increase FTP speed by allowing many concurrent connections to the server. The purpose of this feature is to download many files (a folder) at the same time. 

FTP clients that support concurrent downloads: BitKinex and FileZilla.

3.2 Segmented Downloads. 

Also known as multi-source file transfer. Segmented downloads work similar to the P2P transfer method, as it uses a swarm to transfer files. 

Segmented FTP downloads break up a file into smaller parts, download each piece with a separate connection, and combine each file into one when finished.

For example, you are trying to download a single file with a 1 MBps speed, but you are getting limited to only 100KBps. The feature breaks up the single file into ten parts, each one requiring their separate connection. If each file can be downloaded at 100KBps, then you can accomplish 10x the speed. Apps like uTorrent use a similar pattern.

Some FTP clients that support segmented downloads are CuteFTP Pro and Smart FTP Pro.

3.3 Other Features that can improve FTP speed. 

  • FTP Speed Limits. Make sure that the FTP client does not have any download/upload speed limitation configured. The Speed Limit parameter also comes with Burst Tolerance which can help with low latency connections. Setting the burst tolerance to very high will allow bursty (spiky) speed transfers, instead of smooth speeds. 
  • FTP Passive vs Active mode. If your FTP client is sitting behind a NAT (proxy or VPN), the FTP Passive mode must be configured. Passive mode tends to be slower than active. If your FTP client is directly connected to the Internet and with a dedicated IP address, Active FTP transfer mode can provide faster speeds. 

3.4 How to Speed up FileZilla Transfers? 

To change the concurrent transfer values in FileZilla, go to Edit > Settings > Transfers > [Concurrent Transfers]. In “Maximum Simultaneous Transfers”, notice that Filezilla has 10 as the greatest value.

  • Make sure this value is high so you can see an improvement in file transfer speed. Using a value higher than 10 is not possible in FileZilla because concurrent values may put stress on FTP servers.
  • The “Limit for concurrent downloads and uploads” settings, below can create balanced downloads and uploads. For example, if you limit concurrent uploads to 3, you can only upload 3 files at a time. If you limit concurrent downloads to 7, you cannot download more than 7 files at the same time.
FileZilla concurrent transfers.
  • Check whether you have defined an FTP speed limit for your FTP client. FileZilla FTP client comes with unlimited transfer speeds by default. Check whether a transfer speed limit is defined.
  • In the case of FileZilla, go to Edit > Settings > Transfers > [Speed Limit]. If the “Enable speed limit” box is checked, disable it.
FileZilla Speed Limits

3.5 How to Speed Up CuteFTP Transfers?

The same as FileZilla, you can force CuteFTP to open new connections for multiple transfers. 

  • To speed up CuteFTP through concurrent transfers, go to Tools > Global Options.
CuteFTP optimize speed.
  • In the Global Options, go to Connection. 
  • You can increase the maximum concurrent transfers globally or per site. This feature will allow you to download multiple files from multiple remote servers at the same time via multiple simultaneous connections. 
CuteFTP max concurrent transfers.
  • You can also allow multi-part transfers (segmented downloads) and set the global bandwidth to unlimited. 
CuteFTP multi-part transfers, multi-threads.

4. A step-by-step guide to troubleshooting your slow FTP speed.

Are FTP speeds still slow?

The following step-by-step guide to troubleshooting your FTP will help you eliminate your slow FTP speed. 

4.1 The first test you can do is to perform local FTP speeds. 

  • Install the FTP Client and Server in the same workstation. 
  • The FTP Server has a hostname or IP address, in this case, is “localhost.” 
FileZilla FTP Server.
  • Perform FTP into the local server using the local hostname, “localhost” or “127.0.0.1”. Use whatever username and password you configured on the FTP Server. 
FTP FileZilla client localhost.
  • Now download or upload a file. Transfer a file to your own computer, and check its speed. If you have top speed, that means it is not a problem with your application. We have to dig a bit more into the TCP/IP stack.
  • FTPing to your local computer is only for testing purposes. Now you need to rule out the local area network, and Internet gateway.  

4.2 Let’s Verify the Network. 

Packet loss and delay within your local network (and of course the Internet) can dramatically affect transfer speeds. Delay and packet loss can be caused by overcrowded WiFi, damaged wiring, long distances to the router, etc.

Ping The Gateway. 

The best and easiest way to test the local router or switch for packet loss is with a ping test. 

  • First, let’s find out the IP address of the gateway. 
  • In Windows press Win+R to open Run, then type “cmd”. Open the Command Prompt and type the command “ipconfig”.
Finding your default gateway.
  • Send an extended ping to the Internet gateway, with the command “ping [your gateway IP] -t”.
Reading ping results.
  • Look for the percentage of packet loss and the Round Trip Times RTT average. The closest an RTT is to zero, the better… My RTT time is 59ms which is not so good and this is because I am on a wireless network far away from the gateway. 

Trace the Route Towards the Destination.

You can also use the traceroute diagnosis tool, which is a built-in CLI command available in Windows, Linux, macOS, UNIX-based systems, etc. Traceroute displays the path and measures packet delays. 

Traceroute gives you the result in terms of delay and hostname of each hop towards the destination (FTP Server). Note that most routers and firewalls from ISPs, that receive these traceroute packets, do not send back the ICMP error message “ICMP Time Exceeded,” the key message that gives you hop and delay information.

  • Open the Command Prompt again and type the command “traceroute [destination IP]”. “Tracert” in Windows, and “traceroute” in Linux and macOS. 
  • As an example, let’s verify the path towards “ftp://speedtest.tele2.net/”. How to find the IP? With ping. You can’t ping an “FTP service,” but you can ping the “FTP server”. Ping “speedtest.tele2.net” without the “ftp” and you’ll get a reply. You can also find it when connecting from an FTP client. 
Finding an FTP Server IP.
  • Now, let’s perform a “traceroute” towards the public IP 90.130.70.73. 
Reading the traceroute results.
  • Reading the results. You might see that there are three [2ms, 1ms, 1ms] results for each hop. Those are the three TTL for each hop, and they are response times. The delay to the first hop (192.168.0.1), my Internet gateway took only around 1ms… which is not bad… From the gateway to 192.168.5.1… which is probably the NAT gateway… also resulted pretty fast. 
  • From 192.168.5.1 to 172.21.0.12 (first red arrow) is where things got interesting. The response time was around 77 ms which is slow… Notice that results are cumulative. Another slow response time was around hop 9 (second red arrow). 
  • The response time was slow… probably because the FTP server is geographically far away. 

Performing a Bidirectional MTR Test. 

MTR is a network diagnostic tool that can help you track the network packets that flow from source to destination. It displays where it passes (hops), and the possible origin of a delay.  The MTR tool is an improved version of ICMP traceroute. 

The main differences between MTR and traceroute are:

  • MTR does not rely on ICMP Time Exceeded packets.
  • Combines traceroute and ping results. 
  • It is not limited to three packets per hop.
Bidirectional MTR.

For more information on how to run a bidirectional MTR, refer to the step-by-step guide, Making a bidirectional MTR.

4.3 Use Wired Instead of Wireless.

WiFi causes a lot of delay and packet loss within a LAN.

The latest WiFi standards, such as 802.11n, supports a high-speed bandwidth of up to 300 Mbps. High speeds, good security, and flexibility to move around, make WiFi a popular technology. But WiFi was not designed for frequent and heavy downloading/uploading.

There is something more appropriate. 

A wired connection provides increased speed (low latencies) and security. Ethernet or Fiber wire connections can double or triple the speed + security. For serious FTP downloading, avoid WiFi connectivity. Connect right to your router/access point through a wired cable.

If WiFi is your only option, try sitting as close as possible to the gateway and without any obstructions. 

4.4 Now Let’s Check the Local Router. 

If you performed the SpeedTest as shown before and the results were good, let’s continue. Your Internet connection is good, and your gateway is functional. 

But there might be some crucial settings missing on your local router that are causing that slow FTP speed. 

  • If you are trying to FTP to a remote server, and your speeds are horrible, you will need to check your local router.
  • Your local router might be limiting FTP connections. Make sure the router is forwarding ports 20 and 21 (and port 22 for SSH) in your local router. 
  • Log into your router and configure the ports to map the necessary IP address. 
Port Forwarding.
  • Port forwarding is especially important when the FTP server and client are connected via a NAT router. This configuration requires port forwarding (on the router) and FTP in passive mode (on client and server). 

4.5 Check Whether you are connected to a VPN or Proxy. 

A VPN adds more factors that can slow down an Internet connection. 

The VPN client creates a tunnel and routes encrypted traffic towards the VPN server. The VPN server decrypts and forwards it back to the source. This encryption/decryption process adds a delay (and sometimes huge delay) in speed.

A VPN will not speed up your FTP speed. Try turning it off and then test your FTP speed again.

But having a secure connection might outweigh the small loss of speed. In some particular cases, modern VPNs can play an important role in helping speed up transfer rates. 

How?  

ISPs monitor traffic and shape anything that is consuming too much bandwidth. They limit bandwidth for certain activities, such as P2P, streaming, and heavy downloading/uploading.

A VPN connection might bypass any rules defined by ISPs that throttle bandwidth and government censorship that shapes your traffic. In these circumstances, a VPN tunnel might put an end to bandwidth throttling and help to improve your FTP speed.

A common VPN service is OpenVPN. If you have a Server, the VPN client is easy to set up. Follow this detailed guide to install OpenVPN in a Windows PC Seedbox.

4.6 Testing other file transfer protocols and clients.

As said before, there are many factors that can add up to your slow speed. Yet, choosing light and a well-developed client can contribute to faster FTP transfer rates. 

The FTP client makes a huge difference. You can test with other FTP clients and change the file transfer mechanism. For example, WinSCP is a great client for SCP and SFTP, while Filezilla has a good reputation for FTP and FTPS. 

The following list highlights five popular FTP clients that are light, fast, and powerful. These tools are optimized right out of the box to maximize FTP speed.

  1. FileZilla, the most popular and open-source FTP client/server among administrators. Filezilla is free, light, and updates regularly. If you are looking for speed optimization, it comes with features such as “Concurrent Downloads.” Filezilla supports FTPS and SFTP. If you are looking for a fast client with worldwide support, FileZilla is the right one.
  2. WinSCP another free, fast, and lightweight client. WinSCP client supports FTP, SFTP, FTPS, SCP, and WebDAV. The only limitation is that WinSCP is exclusive to the Windows OS community.
  3. FlashFXP. If you are looking for security and speed, FlashFXP is the right client. It supports FTP, FTPS, and SFTP. However, this client is only supported by Windows.
  4. Transmit. If you are looking for speed and have an Apple computer, Transmit might be your choice. It comes with a “twin-turbo engine,” which boosts rates up to 25x. Transmit can transfer files to your cloud services and still supports traditional protocols such as FTPS, SFTP, and WebDAV. Transmit is only available for MAC and is not free.
  5. CuteFTP Pro. This client comes with a very simple and easy to use interface. CuteFTP Pro has features such as resume support, segmented downloads, and automatic file detection. This client supports all transfer protocols. CuteFTP Pro is not free.
  6. CyberDuck. Another legendary free FTP client. CyberDuck is an open-source client that supports FTP, SFTP, WebDAV, and cloud storage. They provide their own Transparent, client-side encryption called Cryptomator, which helps secure data on the server or cloud storage. 

4.7 Check your Antivirus. 

An Antivirus is the first line of defense against Malware. But despite its many benefits, it can degrade your Internet speed and computer performance. 

But there is a tradeoff. 

Disabling your Antivirus to get better speed and performance, is not a good idea. Your computer infected with Malware is 10x slower than the performance tax that you pay from scanning for viruses. Malware might be the No.1 reason for your slow Internet speed. 

Don’t disable your Antivirus, tweak it for performance and speed. Some antiviruses run passive background quick scans and backups that slightly degrade performance while others do more aggressive real-time scans that can slow down the entire Internet connection. 

If you are getting slow Internet speeds: 

  • Let the Antivirus download the latest virus signatures and disconnect from the Internet. Perform an in-depth scan to find potential Malware. Once finished, restart your computer.
  • You can optimize your AV by not installing features that you don’t need. Also, do not perform “scan all files” every day and add exclusions to other security programs.
  • To do this on Windows, open Windows Security Center and go to “Virus & Threat Protection Settings.” Then go to Exclusions > Add or Remove Exclusions.
Add and remove exclusions in Windows Security.
  • Add exclusions to all your trusted security programs.
  • Also, don’t forget to add exclusion to the FTP Client process, so that your AV is not scanning your FTP and its files every time you use it. 
Add Exclusions Windows Defender.
  • If speed is still slow. Turn off your antivirus temporarily and download a test file from a reliable FTP server. Enable antivirus and perform the same test. If there is a big difference in speed after the test, try using another antivirus. 
  • Some antivirus programs have a lighter footprint on the performance of the system than others. You can try other antiviruses such as Webroot SecureAnywhere AntiVirus, Bitdefender, or Kaspersky’s AV

4.8 Check your Firewall.

A firewall is a similar case to the antivirus. Firewalls defend your system against external threats such as intruders, attacks, Malware, etc., but they take a toll on your system’s performance.  

Firewalls inspect every packet attempting to enter or exit the network, allowing some packets and discarding others. Decision-making on each packet can have a slight degradation on Internet speed. 

Depending on the manufacturer or its configuration, some firewalls create complete traffic bottlenecks.

Verify the Firewall and its Rules. 

  • During the installation, an FTP client like FileZilla will automatically add firewall rules into the Firewall. The firewall will allow all inbound/outbound traffic related to Filezilla. If Windows allows FileZilla, all ports that work with it will be allowed as well (ports such as 21, 22, 22221, 22222).
Add inbound/outbound rules for the FTP client.
  • Unless your local firewall is blocking important ports, it will not degrade the speed of your FTP. As a test, turn off your local firewall temporarily, download a test file from a reliable source, and check your speed. Turn it on and perform the same test.
  • If you see a lower performance when the firewall is on, lower the security level of your firewall, or use another firewall like Bitdefender.
  • If you are using any kind of Linux distro, try any of the best Linux firewalls, which will reduce the burden on your computer and Internet speed.

4.9 Look for Other Apps that might be Hurting your Performance. 

Online activities such as streaming, browsing or P2P, can be invasive to your bandwidth. 

By default, applications and programs are allowed to use as much bandwidth as they need. But having too many of them using the Internet at the same time will degrade your overall speed.

The fewer applications consume your bandwidth, the faster FTP client will download. To allocate more bandwidth to FTP downloads, close any other Internet invasive programs.

  • Check the network usage in the task manager. If it is Windows, open your Task Manager via (ctrl+alt+del). 
  • Sort the processes in the Network tab and check the highest consumers. Processes on the top places are the ones consuming more bandwidth.
Optimizing bandwidth for computer.
  • For more details related to network usage in Windows, use The Resource Monitor. To open it, go to Task manager > Performance > Open Resource Monitor (on the bottom). 
  • Go to the Network tab and find Network Activity. This chart shows a good amount of information on current processes, addresses and even packets sent and received. Look for the ones that are using the most bandwidth or sending/receiving packets.
Network Activity - Resource Monitor

Summary: Why are FTP speeds so slow and what can you do about it?

So your FTP speed is slow? 

Purchasing the fastest Internet plan and lowest latency connection might be the most obvious choice. Widening the pipe will definitely allow more flow to go through.

But wait… Most of the time, other factors might be affecting your speed. 

First, get familiar with your resources. Know the limitations of your Internet plan, bandwidth, computers, network, and the FTP server. With this information in hand, you’ll be able to predict download times. Maybe your FTP download speeds are not so bad, but your expectations are too high.

Double confirm your bandwidth and convert it to other metrics. Also, inform yourself if you are paying for symmetrical or asymmetrical bandwidth. Your upload speeds might be much much lower than your download speeds. 

Once you know your stuff and have tweaked them properly, go ahead and buy a faster bandwidth.

The FTP client (and server) can be optimized to get the maximum speed. Enable concurrent connections, and if possible segmented downloads as well. If you have a limitation on FTP speed configured on the client, that could be an apparent reason for the problem. Sometimes testing with other file transfer mechanisms and clients may solve your slow FTP speeds. 

We hope that this guide to eliminate slow FTP speeds was informative and helpful. Please, if you have questions, let us know in the comments below.