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IMAP stands for Internet Message Access Protocol. It is an application layer protocol which is used to receive the emails from the mail server. It is the most commonly used protocols like POP3 for retrieving the emails.

It also follows the client/server model. On one side, we have an IMAP client, which is a process running on a computer. On the other side, we have an IMAP server, which is also a process running on another computer. Both computers are connected through a network.

Source: https://www.javatpoint.com/imap-protocol

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IMAP stands for Internet Message Access Protocol. It is an application layer protocol which is used to receive the emails from the mail server. It is the most commonly used protocols like POP3 for retrieving the emails.

It also follows the client/server model. On one side, we have an IMAP client, which is a process running on a computer. On the other side, we have an IMAP server, which is also a process running on another computer. Both computers are connected through a network.

The IMAP protocol resides on the TCP/IP transport layer which means that it implicitly uses the reliability of the protocol. Once the TCP connection is established between the IMAP client and IMAP server, the IMAP server listens to the port 143 by default, but this port number can also be changed.

By default, there are two ports used by IMAP:

Port 143: It is a non-encrypted IMAP port.

Port 993: This port is used when IMAP client wants to connect through IMAP securely.

Why should we use IMAP instead of POP3 protocol?

POP3 is becoming the most popular protocol for accessing the TCP/IP mailboxes. It implements the offline mail access model, which means that the mails are retrieved from the mail server on the local machine, and then deleted from the mail server. Nowadays, millions of users use the POP3 protocol to access the incoming mails. Due to the offline mail access model, it cannot be used as much. The online model we would prefer in the ideal world. In the online model, we need to be connected to the internet always. The biggest problem with the offline access using POP3 is that the mails are permanently removed from the server, so multiple computers cannot access the mails. The solution to this problem is to store the mails at the remote server rather than on the local server. The POP3 also faces another issue, i.e., data security and safety. The solution to this problem is to use the disconnected access model, which provides the benefits of both online and offline access. In the disconnected access model, the user can retrieve the mail for local use as in the POP3 protocol, and the user does not need to be connected to the internet continuously. However, the changes made to the mailboxes are synchronized between the client and the server. The mail remains on the server so different applications in the future can access it. When developers recognized these benefits, they made some attempts to implement the disconnected access model. This is implemented by using the POP3 commands that provide the option to leave the mails on the server. This works, but only to a limited extent, for example, keeping track of which messages are new or old become an issue when both are retrieved and left on the server. So, the POP3 lacks some features which are required for the proper disconnected access model.

In the mid-1980s, the development began at Stanford University on a new protocol that would provide a more capable way of accessing the user mailboxes. The result was the development of the interactive mail access protocol, which was later renamed as Internet Message Access Protocol.

IMAP History and Standards

The first version of IMAP was formally documented as an internet standard was IMAP version 2, and in RFC 1064, and was published in July 1988. It was updated in RFC 1176, August 1990, retaining the same version. So they created a new document of version 3 known as IMAP3. In RFC 1203, which was published in February 1991. However, IMAP3 was never accepted by the market place, so people kept using IMAP2. The extension to the protocol was later created called IMAPbis, which added support for Multipurpose Internet Mail Extensions (MIME) to IMAP. This was a very important development due to the usefulness of MIME. Despite this, IMAPbis was never published as an RFC. This may be due to the problems associated with the IMAP3. In December 1994, IMAP version 4, i.e., IMAP4 was published in two RFCs, i.e., RFC 1730 describing the main protocol and RFC 1731 describing the authentication mechanism for IMAP 4. IMAP 4 is the current version of IMAP, which is widely used today. It continues to be refined, and its latest version is actually known as IMAP4rev1 and is defined in RFC 2060. It is most recently updated in RFC 3501.

IMAP Features

IMAP was designed for a specific purpose that provides a more flexible way of how the user accesses the mailbox. It can operate in any of the three modes, i.e., online, offline, and disconnected mode. Out of these, offline and disconnected modes are of interest to most users of the protocol.

The following are the features of an IMAP protocol:

Access and retrieve mail from remote server: The user can access the mail from the remote server while retaining the mails in the remote server.

Set message flags: The message flag is set so that the user can keep track of which message he has already seen.

Manage multiple mailboxes: The user can manage multiple mailboxes and transfer messages from one mailbox to another. The user can organize them into various categories for those who are working on various projects.

Determine information prior to downloading: It decides whether to retrieve or not before downloading the mail from the mail server.

Downloads a portion of a message: It allows you to download the portion of a message, such as one body part from the mime-multi part. This can be useful when there are large multimedia files in a short-text element of a message.

Organize mails on the server: In case of POP3, the user is not allowed to manage the mails on the server. On the other hand, the users can organize the mails on the server according to their requirements like they can create, delete or rename the mailbox on the server.

Search: Users can search for the contents of the emails.

Check email-header: Users can also check the email-header prior to downloading.

Create hierarchy: Users can also create the folders to organize the mails in a hierarchy.

IMAP General Operation

1. The IMAP is a client-server protocol like POP3 and most other TCP/IP application protocols. The IMAP4 protocol functions only when the IMAP4 must reside on the server where the user mailboxes are located. In c the POP3 does not necessarily require the same physical server that provides the SMTP services. Therefore, in the case of the IMAP protocol, the mailbox must be accessible to both SMTP for incoming mails and IMAP for retrieval and modifications.

2. The IMAP uses the Transmission Control Protocol (TCP) for communication to ensure the delivery of data and also received in the order.

3. The IMAP4 listens on a well-known port, i.e., port number 143, for an incoming connection request from the IMAP4 client.

Let's understand the IMAP protocol through a simple example.

The IMAP protocol synchronizes all the devices with the main server. Let's suppose we have three devices desktop, mobile, and laptop as shown in the above figure. If all these devices are accessing the same mailbox, then it will be synchronized with all the devices. Here, synchronization means that when mail is opened by one device, then it will be marked as opened in all the other devices, if we delete the mail, then the mail will also be deleted from all the other devices. So, we have synchronization between all the devices. In IMAP, we can see all the folders like spam, inbox, sent, etc. We can also create our own folder known as a custom folder that will be visible in all the other devices.

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IMAP Protocol | Internet Message Access Protocol - javatpoint

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IMAP Protocol | Internet Message Access Protocol with Tutorial, features, types of computer network, components, cables and connectors, Intranet, Uses Of Computer Network, Hub, Software and Hardware, etc.

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The SSH protocol (also referred to as Secure Shell) is a method for secure remote login from one computer to another. It provides several alternative options for strong authentication, and it protects the communications security and integrity with strong encryption. It is a secure alternative to the non-protected login protocols (such as telnet, rlogin) and insecure file transfer methods (such as FTP).

Source: https://www.ssh.com/academy/ssh/protocol

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This page is about the SSH protocol. For the company behind it, see SSH Communications Security. For using the Linux ssh command, see ssh command usage. For SSH clients, servers, and technical information, see SSH (Secure Shell) home page.

The SSH protocol (also referred to as Secure Shell) is a method for secure remote login from one computer to another. It provides several alternative options for strong authentication, and it protects the communications security and integrity with strong encryption. It is a secure alternative to the non-protected login protocols (such as telnet, rlogin) and insecure file transfer methods (such as FTP).

Typical uses of the SSH protocol

The protocol is used in corporate networks for:

providing secure access for users and automated processes

interactive and automated file transfers

issuing remote commands

managing network infrastructure and other mission-critical system components.

How does the SSH protocol work

The protocol works in the client-server model, which means that the connection is established by the SSH client connecting to the SSH server. The SSH client drives the connection setup process and uses public key cryptography to verify the identity of the SSH server. After the setup phase the SSH protocol uses strong symmetric encryption and hashing algorithms to ensure the privacy and integrity of the data that is exchanged between the client and server.

The figure below presents a simplified setup flow of a secure shell connection.

Strong authentication with SSH keys

There are several options that can be used for user authentication. The most common ones are passwords and public key authentication.

The public key authentication method is primarily used for automation and sometimes by system administrators for single sign-on. It has turned out to be much more widely used than we ever anticipated. The idea is to have a cryptographic key pair - public key and private key - and configure the public key on a server to authorize access and grant anyone who has a copy of the private key access to the server. The keys used for authentication are called SSH keys. Public key authentication is also used with smartcards, such as the CAC and PIV cards used by US government.

The main use of key-based authentication is to enable secure automation. Automated secure shell file transfers are used to seamlessly integrate applications and also for automated systems & configuration management.

We have found that large organizations have way more SSH keys than they imagine, and managing SSH keys has become very important. SSH keys grant access as user names and passwords do. They require a similar provisioning and termination processes.

In some cases we have found several million SSH keys authorizing access into production servers in customer environments, with 90% of the keys actually being unused and representing access that was provisioned but never terminated. Ensuring proper policies, processes, and audits also for SSH usage is critical for proper identity and access management. Traditional identity management projects have overlooked as much as 90% of all credentials by ignoring SSH keys. We provide services and tools for implementing SSH key management.

SSH provides strong encryption and integrity protection

Once a connection has been established between the SSH client and server, the data that is transmitted is encrypted according to the parameters negotiated in the setup. During the negotiation the client and server agree on the symmetric encryption algorithm to be used and generate the encryption key that will be used. The traffic between the communicating parties is protected with industry standard strong encryption algorithms (such as AES (Advanced Encryption Standard)), and the SSH protocol also includes a mechanism that ensures the integrity of the transmitted data by using standard hash algorithms (such as SHA-2 (Standard Hashing Algorithm)).

IETF SSH standard and detailed technical documentation

The core protocol

When the SSH protocol became popular, Tatu Ylonen took it to the IETF for standardization. It is now an internet standard that is described in the following documents:

RFC 4251 - The Secure Shell (SSH) Protocol Architecture

RFC 4253 - The Secure Shell (SSH) Transport Layer Protocol

RFC 4252 - The Secure Shell (SSH) Authentication Protocol

RFC 4254 - The Secure Shell (SSH) Connection Protocol

SFTP file transfer protocol

The SFTP (SSH File Transfer Protocol) is probably the most widely used secure file transfer protocol today. It runs over SSH, and is currently documented in

draft-ietf-secsh-filexfer-02

Public key file format

The public key file format is not a formal standard (it is an informational document), but many implementations support this format.

RFC 4716 - The Secure Shell (SSH) Public Key File Format

How to Cite SSH

To cite SSH in a research paper, please use the following:

Tatu Ylonen: SSH - Secure Login Connections over the Internet.
Proceedings of the 6th USENIX Security Symposium, pp. 37-42, USENIX, 1996.

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SSH protocol is the standard for strong authentication, secure connection, and encrypted file transfers. We developed it.

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SSH protocol is the standard for strong authentication, secure connection, and encrypted file transfers. We developed it.

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Dynamic Host Configuration Protocol (DHCP) is a client/server protocol that automatically provides an Internet Protocol (IP) host with its IP address and other related configuration information such as the subnet mask and default gateway. RFCs 2131 and 2132 define DHCP as an Internet Engineering Task Force (IETF) standard based on Bootstrap Protocol (BOOTP), a protocol with which DHCP shares many implementation details. DHCP allows hosts to obtain required TCP/IP configuration information from a DHCP server.

Source: https://docs.microsoft.com/en-us/windows-server/networking/technologies/dhcp/dhcp-top

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Applies to: Windows Server 2022, Windows Server 2019, Windows Server 2016

You can use this topic for a brief overview of DHCP in Windows Server 2016.

Note

In addition to this topic, the following DHCP documentation is available.

Dynamic Host Configuration Protocol (DHCP) is a client/server protocol that automatically provides an Internet Protocol (IP) host with its IP address and other related configuration information such as the subnet mask and default gateway. RFCs 2131 and 2132 define DHCP as an Internet Engineering Task Force (IETF) standard based on Bootstrap Protocol (BOOTP), a protocol with which DHCP shares many implementation details. DHCP allows hosts to obtain required TCP/IP configuration information from a DHCP server.

Windows Server 2016 includes DHCP Server, which is an optional networking server role that you can deploy on your network to lease IP addresses and other information to DHCP clients. All Windows-based client operating systems include the DHCP client as part of TCP/IP, and DHCP client is enabled by default.

Why use DHCP?

Every device on a TCP/IP-based network must have a unique unicast IP address to access the network and its resources. Without DHCP, IP addresses for new computers or computers that are moved from one subnet to another must be configured manually; IP addresses for computers that are removed from the network must be manually reclaimed.

With DHCP, this entire process is automated and managed centrally. The DHCP server maintains a pool of IP addresses and leases an address to any DHCP-enabled client when it starts up on the network. Because the IP addresses are dynamic (leased) rather than static (permanently assigned), addresses no longer in use are automatically returned to the pool for reallocation.

The network administrator establishes DHCP servers that maintain TCP/IP configuration information and provide address configuration to DHCP-enabled clients in the form of a lease offer. The DHCP server stores the configuration information in a database that includes:

Valid TCP/IP configuration parameters for all clients on the network.

Valid IP addresses, maintained in a pool for assignment to clients, as well as excluded addresses.

Reserved IP addresses associated with particular DHCP clients. This allows consistent assignment of a single IP address to a single DHCP client.

The lease duration, or the length of time for which the IP address can be used before a lease renewal is required.

A DHCP-enabled client, upon accepting a lease offer, receives:

A valid IP address for the subnet to which it is connecting.

Requested DHCP options, which are additional parameters that a DHCP server is configured to assign to clients. Some examples of DHCP options are Router (default gateway), DNS Servers, and DNS Domain Name.

Benefits of DHCP

DHCP provides the following benefits.

Reliable IP address configuration. DHCP minimizes configuration errors caused by manual IP address configuration, such as typographical errors, or address conflicts caused by the assignment of an IP address to more than one computer at the same time.

Reduced network administration. DHCP includes the following features to reduce network administration:

Centralized and automated TCP/IP configuration.

The ability to define TCP/IP configurations from a central location.

The ability to assign a full range of additional TCP/IP configuration values by means of DHCP options.

The efficient handling of IP address changes for clients that must be updated frequently, such as those for portable devices that move to different locations on a wireless network.

The forwarding of initial DHCP messages by using a DHCP relay agent, which eliminates the need for a DHCP server on every subnet.

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Dynamic Host Configuration Protocol (DHCP)

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Applies to: Windows Server 2022, Windows Server 2019, Windows Server 2016 You can use this topic for a brief overview of DHCP in Windows Server 2016. Note In addition to this topic, the following DHCP documentation is available.

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POP3 (Post Office Protocol) is a very common protocol for getting emails from a mail server over a TCP connection. POP3 does not support folders, unlike the more recent IMAP, which is harder to implement because of its more complex structure.

Clients usually retrieve all messages and then delete them from the server, but POP3 does allow retaining a copy on the server. Nearly all email servers and clients currently support POP3.

Source: https://developer.mozilla.org/en-US/docs/Glossary/POP

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POP3 (Post Office Protocol) is a very common protocol for getting emails from a mail server over a TCP connection. POP3 does not support folders, unlike the more recent IMAP, which is harder to implement because of its more complex structure.

Clients usually retrieve all messages and then delete them from the server, but POP3 does allow retaining a copy on the server. Nearly all email servers and clients currently support POP3.

See also

POP on Wikipedia

RFC 1734 (Specification of POP3 authentication mechanism)

RFC 1939 (Specification of POP3)

RFC 2449 (Specification of POP3 extension mechanism)

MDN Web Docs Glossary:

IMAP

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POP3 - MDN Web Docs Glossary: Definitions of Web-related terms | MDN

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POP3 (Post Office Protocol) is a very common protocol for getting emails from a mail server over a TCP connection. POP3 does not support folders, unlike the more recent IMAP, which is harder to implement because of its more complex structure.

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TCP stands for Transmission Control Protocol a communications standard that enables application programs and computing devices to exchange messages over a network. It is designed to send packets across the internet and ensure the successful delivery of data and messages over networks.

TCP is one of the basic standards that define the rules of the internet and is included within the standards defined by the Internet Engineering Task Force (IETF). It is one of the most commonly used protocols within digital network communications and ensures end-to-end data delivery.

Source: https://www.fortinet.com/resources/cyberglossary/tcp-ip

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What is TCP?

TCP stands for Transmission Control Protocol a communications standard that enables application programs and computing devices to exchange messages over a network. It is designed to send packets across the internet and ensure the successful delivery of data and messages over networks.

TCP is one of the basic standards that define the rules of the internet and is included within the standards defined by the Internet Engineering Task Force (IETF). It is one of the most commonly used protocols within digital network communications and ensures end-to-end data delivery.

TCP organizes data so that it can be transmitted between a server and a client. It guarantees the integrity of the data being communicated over a network. Before it transmits data, TCP establishes a connection between a source and its destination, which it ensures remains live until communication begins. It then breaks large amounts of data into smaller packets, while ensuring data integrity is in place throughout the process.

As a result, high-level protocols that need to transmit data all use TCP Protocol. Examples include peer-to-peer sharing methods like File Transfer Protocol (FTP), Secure Shell (SSH), and Telnet. It is also used to send and receive email through Internet Message Access Protocol (IMAP), Post Office Protocol (POP), and Simple Mail Transfer Protocol (SMTP), and for web access through the Hypertext Transfer Protocol (HTTP).

An alternative to TCP is the User Datagram Protocol (UDP), which is used to establish low-latency connections between applications and decrease transmissions time. TCP can be an expensive network tool as it includes absent or corrupted packets and protects data delivery with controls like acknowledgments, connection startup, and flow control.

UDP does not provide error connection or packet sequencing nor does it signal a destination before it delivers data, which makes it less reliable but less expensive. As such, it is a good option for time-sensitive situations, such as Domain Name System (DNS) lookup, Voice over Internet Protocol (VoIP), and streaming media.

What is IP?

The Internet Protocol (IP) is the method for sending data from one device to another across the internet. Every device has an IP address that uniquely identifies it and enables it to communicate with and exchange data with other devices connected to the internet.

IP is responsible for defining how applications and devices exchange packets of data with each other. It is the principal communications protocol responsible for the formats and rules for exchanging data and messages between computers on a single network or several internet-connected networks. It does this through the Internet Protocol Suite (TCP/IP), a group of communications protocols that are split into four abstraction layers.

IP is the main protocol within the internet layer of the TCP/IP. Its main purpose is to deliver data packets between the source application or device and the destination using methods and structures that place tags, such as address information, within data packets.

TCP vs. IP: What is the Difference?

TCP and IP are separate protocols that work together to ensure data is delivered to its intended destination within a network. IP obtains and defines the address-the IP address-of the application or device the data must be sent to. TCP is then responsible for transporting and routing data through the network architecture and ensuring it gets delivered to the destination application or device that IP has defined.

In other words, the IP address is akin to a phone number assigned to a smartphone. TCP is the computer networking version of the technology used to make the smartphone ring and enable its user to talk to the person who called them. The two protocols are frequently used together and rely on each other for data to have a destination and safely reach it, which is why the process is regularly referred to as TCP/IP.

How Does TCP/IP Work?

The TCP/IP model is the default method of data communication on the Internet. It was developed by the United States Department of Defense to enable the accurate and correct transmission of data between devices. It breaks messages into packets to avoid having to resend the entire message in case it encounters a problem during transmission. Packets are automatically reassembled once they reach their destination. Every packet can take a different route between the source and the destination computer, depending on whether the original route used becomes congested or unavailable.

TCP/IP divides communication tasks into layers that keep the process standardized, without hardware and software providers doing the management themselves. The data packets must pass through four layers before they are received by the destination device, then TCP/IP goes through the layers in reverse order to put the message back into its original format.

As a connection based protocol, the TCP establishes and maintains a connection between applications or devices until they finish exchanging data. It determines how the original message should be broken into packets, numbers and reassembles the packets, and sends them on to other devices on the network, such as routers, security gateways, and switches, then on to their destination. TCP also sends and receives packets from the network layer, handles the transmission of any dropped packets, manages flow control, and ensures all packets reach their destination.

A good example of how this works in practice is when an email is sent using SMTP from an email server. To start the process, the TCP layer in the server divides the message into packets, numbers them, and forwards them to the IP layer, which then transports each packet to the destination email server. When packets arrive, they are handed back to the TCP layer to be reassembled into the original message format and handed back to the email server, which delivers the message to a user's email inbox.

TCP/IP uses a three-way handshake to establish a connection between a device and a server, which ensures multiple TCP socket connections can be transferred in both directions concurrently. Both the device and server must synchronize and acknowledge packets before communication begins, then they can negotiate, separate, and transfer TCP socket connections.

The 4 Layers of the TCP/IP Model

The TCP/IP model defines how devices should transmit data between them and enables communication over networks and large distances. The model represents how data is exchanged and organized over networks. It is split into four layers, which set the standards for data exchange and represent how data is handled and packaged when being delivered between applications, devices, and servers.

The four layers of the TCP/IP model are as follows:

1. Datalink layer: The datalink layer defines how data should be sent, handles the physical act of sending and receiving data, and is responsible for transmitting data between applications or devices on a network. This includes defining how data should be signaled by hardware and other transmission devices on a network, such as a computer's device driver, an Ethernet cable, a network interface card (NIC), or a wireless network. It is also referred to as the link layer, network access layer, network interface layer, or physical layer and is the combination of the physical and data link layers of the Open Systems Interconnection (OSI) model, which standardizes communications functions on computing and telecommunications systems.

2. Internet layer: The internet layer is responsible for sending packets from a network and controlling their movement across a network to ensure they reach their destination. It provides the functions and procedures for transferring data sequences between applications and devices across networks.

3. Transport layer: The transport layer is responsible for providing a solid and reliable data connection between the original application or device and its intended destination. This is the level where data is divided into packets and numbered to create a sequence. The transport layer then determines how much data must be sent, where it should be sent to, and at what rate. It ensures that data packets are sent without errors and in sequence and obtains the acknowledgment that the destination device has received the data packets.

4. Application layer: The application layer refers to programs that need TCP/IP to help them communicate with each other. This is the level that users typically interact with, such as email systems and messaging platforms. It combines the session, presentation, and application layers of the OSI model.

Are Your Data Packets Private Over TCP/IP?

Data packets sent over TCP/IP are not private, which means they can be seen or intercepted. For this reason, it is vital to avoid using public Wi-Fi networks for sending private data and to ensure information is encrypted. One way to encrypt data being shared through TCP/IP is through a virtual private network (VPN).

What is My TCP/IP Address?

A TCP/IP address may be required to configure a network and is most likely required in a local network.

Finding a public IP address is a simple process that can be discovered using various online tools. These tools quickly detect the IP address of the device being used, along with the user's host IP address, internet service provider (ISP), remote port, and the type of browser, device, and operating system they are using.

Another way to discover the TCP/IP is through the administration page of a router, which displays the user's current public IP address, the router's IP address, subnet mask, and other network information.

How Fortinet Can Help?

Fortinet enables organizations to securely share and transmit data through the TCP/IP model with its FortiGate Internet Protocol security (IPsec)/secure sockets layer (SSL) VPN solutions. Fortinet's high-performance, scalable crypto VPNs protect organizations and their users from advanced cyber attacks, such as man-in-the-middle (MITM) attacks, and the threat of data loss while data is in motion at high speed. This is crucial for data being transmitted through TCP/IP, which does not protect data packets while they are in motion.

The Fortinet VPN solutions secure organizations' communications across the internet, over multiple networks, and between endpoints. It does this through both IPsec and SSL technologies, using the Fortinet FortiASIC hardware acceleration to guarantee high-performance communications and data privacy.

Fortinet's VPNs mask a user's IP address and create a private connection for them to share data regardless of the security of the internet connection they are using. They establish secure connections by encrypting the data being transmitted between applications and devices. This eliminates the risk of sensitive data being exposed to third parties while being transferred over TCP/IP, in addition to hiding the users' browsing histories, IP addresses, locations, web activities, and other device information.

FAQs

What is TCP used for?

TCP enables data to be transferred between applications and devices on a network and is used in the TCP IP model. It is designed to break down a message, such as an email, into packets of data to ensure the message reaches its destination successfully and as quickly as possible.

What does TCP mean?

TCP meaning Transmission Control Protocol, is a communications standard for delivering data and messages through networks. TCP is a basic standard that defines the rules of the internet and is a common protocol used to deliver data in digital network communications.

What is TCP and what are its types?

TCP is a protocol or standard used to ensure data is successfully delivered from one application or device to another. TCP is part of the Transmission Control Protocol/Internet Protocol (TCP/IP), which is a suite of protocols originally developed by the U.S. Department of Defense to support the construction of the internet. The TCP/IP model consists of several types of protocols, including TCP and IP, Address Resolution Protocol (ARP), Internet Control Message Protocol (ICMP), Reverse Address Resolution Protocol (RARP), and User Datagram Protocol (UDP).

TCP is the most commonly used of these protocols and accounts for the most traffic used on a TCP/IP network. UDP is an alternative to TCP that does not provide error correction, is less reliable, and has less overhead, which makes it ideal for streaming.

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What is Transmission Control Protocol TCP/IP Model?

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What is TCP? TCP stands for Transmission Control Protocol a communications standard that enables application programs and computing devices to exchange messages over a network. It is designed to send packets across the internet and ensure the successful delivery of data and messages over networks.

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Poner aqui una descripción.

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HTTP is a protocol for fetching resources such as HTML documents. It is the foundation of any data exchange on the Web and it is a client-server protocol, which means requests are initiated by the recipient, usually the Web browser. A complete document is reconstructed from the different sub-documents fetched, for instance, text, layout description, images, videos, scripts, and more.

Source: https://developer.mozilla.org/en-US/docs/Web/HTTP/Overview

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HTTP is a protocol for fetching resources such as HTML documents. It is the foundation of any data exchange on the Web and it is a client-server protocol, which means requests are initiated by the recipient, usually the Web browser. A complete document is reconstructed from the different sub-documents fetched, for instance, text, layout description, images, videos, scripts, and more.

Clients and servers communicate by exchanging individual messages (as opposed to a stream of data). The messages sent by the client, usually a Web browser, are called requests and the messages sent by the server as an answer are called responses.

Designed in the early 1990s, HTTP is an extensible protocol which has evolved over time. It is an application layer protocol that is sent over TCP, or over a TLS-encrypted TCP connection, though any reliable transport protocol could theoretically be used. Due to its extensibility, it is used to not only fetch hypertext documents, but also images and videos or to post content to servers, like with HTML form results. HTTP can also be used to fetch parts of documents to update Web pages on demand.

HTTP is a client-server protocol: requests are sent by one entity, the user-agent (or a proxy on behalf of it). Most of the time the user-agent is a Web browser, but it can be anything, for example, a robot that crawls the Web to populate and maintain a search engine index.

Each individual request is sent to a server, which handles it and provides an answer called the response. Between the client and the server there are numerous entities, collectively called proxies, which perform different operations and act as gateways or caches, for example.

In reality, there are more computers between a browser and the server handling the request: there are routers, modems, and more. Thanks to the layered design of the Web, these are hidden in the network and transport layers. HTTP is on top, at the application layer. Although important for diagnosing network problems, the underlying layers are mostly irrelevant to the description of HTTP.

The user-agent is any tool that acts on behalf of the user. This role is primarily performed by the Web browser, but it may also be performed by programs used by engineers and Web developers to debug their applications.

The browser is always the entity initiating the request. It is never the server (though some mechanisms have been added over the years to simulate server-initiated messages).

To display a Web page, the browser sends an original request to fetch the HTML document that represents the page. It then parses this file, making additional requests corresponding to execution scripts, layout information (CSS) to display, and sub-resources contained within the page (usually images and videos). The Web browser then combines these resources to present the complete document, the Web page. Scripts executed by the browser can fetch more resources in later phases and the browser updates the Web page accordingly.

A Web page is a hypertext document. This means some parts of the displayed content are links, which can be activated (usually by a click of the mouse) to fetch a new Web page, allowing the user to direct their user-agent and navigate through the Web. The browser translates these directions into HTTP requests, and further interprets the HTTP responses to present the user with a clear response.

On the opposite side of the communication channel is the server, which serves the document as requested by the client. A server appears as only a single machine virtually; but it may actually be a collection of servers sharing the load (load balancing), or other software (such as caches, a database server, or e-commerce servers), totally or partially generating the document on demand.

A server is not necessarily a single machine, but several server software instances can be hosted on the same machine. With HTTP/1.1 and the Host header, they may even share the same IP address.

Between the Web browser and the server, numerous computers and machines relay the HTTP messages. Due to the layered structure of the Web stack, most of these operate at the transport, network or physical levels, becoming transparent at the HTTP layer and potentially having a significant impact on performance. Those operating at the application layers are generally called proxies. These can be transparent, forwarding on the requests they receive without altering them in any way, or non-transparent, in which case they will change the request in some way before passing it along to the server. Proxies may perform numerous functions:

caching (the cache can be public or private, like the browser cache)

filtering (like an antivirus scan or parental controls)

load balancing (to allow multiple servers to serve different requests)

authentication (to control access to different resources)

logging (allowing the storage of historical information)

HTTP is generally designed to be simple and human-readable, even with the added complexity introduced in HTTP/2 by encapsulating HTTP messages into frames. HTTP messages can be read and understood by humans, providing easier testing for developers, and reduced complexity for newcomers.

Introduced in HTTP/1.0, HTTP headers make this protocol easy to extend and experiment with. New functionality can even be introduced by a simple agreement between a client and a server about a new header's semantics.

HTTP is stateless: there is no link between two requests being successively carried out on the same connection. This immediately has the prospect of being problematic for users attempting to interact with certain pages coherently, for example, using e-commerce shopping baskets. But while the core of HTTP itself is stateless, HTTP cookies allow the use of stateful sessions. Using header extensibility, HTTP Cookies are added to the workflow, allowing session creation on each HTTP request to share the same context, or the same state.

A connection is controlled at the transport layer, and therefore fundamentally out of scope for HTTP. HTTP doesn't require the underlying transport protocol to be connection-based; it only requires it to be reliable, or not lose messages (at minimum, presenting an error in such cases). Among the two most common transport protocols on the Internet, TCP is reliable and UDP isn't. HTTP therefore relies on the TCP standard, which is connection-based.

Before a client and server can exchange an HTTP request/response pair, they must establish a TCP connection, a process which requires several round-trips. The default behavior of HTTP/1.0 is to open a separate TCP connection for each HTTP request/response pair. This is less efficient than sharing a single TCP connection when multiple requests are sent in close succession.

In order to mitigate this flaw, HTTP/1.1 introduced pipelining (which proved difficult to implement) and persistent connections: the underlying TCP connection can be partially controlled using the Connection header. HTTP/2 went a step further by multiplexing messages over a single connection, helping keep the connection warm and more efficient.

Experiments are in progress to design a better transport protocol more suited to HTTP. For example, Google is experimenting with QUIC which builds on UDP to provide a more reliable and efficient transport protocol.

This extensible nature of HTTP has, over time, allowed for more control and functionality of the Web. Cache and authentication methods were functions handled early in HTTP history. The ability to relax the origin constraint, by contrast, was only added in the 2010s.

Here is a list of common features controllable with HTTP:

Caching: How documents are cached can be controlled by HTTP. The server can instruct proxies and clients about what to cache and for how long. The client can instruct intermediate cache proxies to ignore the stored document.

Relaxing the origin constraint: To prevent snooping and other privacy invasions, Web browsers enforce strict separation between websites. Only pages from thesame origin can access all the information of a Web page. Though such a constraint is a burden to the server, HTTP headers can relax this strict separation on the server side, allowing a document to become a patchwork of information sourced from different domains; there could even be security-related reasons to do so.

Authentication: Some pages may be protected so that only specific users can access them. Basic authentication may be provided by HTTP, either using theWWW-Authenticate and similar headers, or by setting a specific session using HTTP cookies.

Proxy and tunneling: Servers or clients are often located on intranets and hide their true IP address from other computers. HTTP requests then go through proxies to cross this network barrier. Not all proxies are HTTP proxies. The SOCKS protocol, for example, operates at a lower level. Other protocols, like ftp, can be handled by these proxies.

Sessions: Using HTTP cookies allows you to link requests with the state of the server. This creates sessions, despite basic HTTP being a state-less protocol. This is useful not only for e-commerce shopping baskets, but also for any site allowing user configuration of the output.

When a client wants to communicate with a server, either the final server or an intermediate proxy, it performs the following steps:

1. Open a TCP connection: The TCP connection is used to send a request, or several, and receive an answer. The client may open a new connection, reuse an existing connection, or open several TCP connections to the servers.

2. Send an HTTP message: HTTP messages (before HTTP/2) are human-readable. With HTTP/2, these simple messages are encapsulated in frames, making them impossible to read directly, but the principle remains the same. For example:

3. Read the response sent by the server, such as:

 <! DOCTYPE html > ... (here come the 29769 bytes of the requested web page)

4. Close or reuse the connection for further requests.

If HTTP pipelining is activated, several requests can be sent without waiting for the first response to be fully received. HTTP pipelining has proven difficult to implement in existing networks, where old pieces of software coexist with modern versions. HTTP pipelining has been superseded in HTTP/2 with more robust multiplexing requests within a frame.

HTTP messages, as defined in HTTP/1.1 and earlier, are human-readable. In HTTP/2, these messages are embedded into a binary structure, a frame, allowing optimizations like compression of headers and multiplexing. Even if only part of the original HTTP message is sent in this version of HTTP, the semantics of each message is unchanged and the client reconstitutes (virtually) the original HTTP/1.1 request. It is therefore useful to comprehend HTTP/2 messages in the HTTP/1.1 format.

There are two types of HTTP messages, requests and responses, each with its own format.

An example HTTP request:

Requests consist of the following elements:

An HTTP method, usually a verb like GET, POST, or a noun like OPTIONS or HEAD that defines the operation the client wants to perform. Typically, a client wants to fetch a resource (usingGET) or post the value of an HTML form (using POST), though more operations may be needed in other cases.

The path of the resource to fetch; the URL of the resource stripped from elements that are obvious from the context, for example without the protocol (http://), the domain (here, developer.mozilla.org), or the TCP port (here, 80).

The version of the HTTP protocol.

Optional headers that convey additional information for the servers.

A body, for some methods like POST, similar to those in responses, which contain the resource sent.

An example response:

Responses consist of the following elements:

The version of the HTTP protocol they follow.

A status code, indicating if the request was successful or not, and why.

A status message, a non-authoritative short description of the status code.

HTTP headers, like those for requests.

Optionally, a body containing the fetched resource.

The most commonly used API based on HTTP is the XMLHttpRequest API, which can be used to exchange data between a user agent and a server. The modernFetch API provides the same features with a more powerful and flexible feature set.

Another API, server-sent events, is a one-way service that allows a server to send events to the client, using HTTP as a transport mechanism. Using theEventSource interface, the client opens a connection and establishes event handlers. The client browser automatically converts the messages that arrive on the HTTP stream into appropriateEvent objects. Then it delivers them to the event handlers that have been registered for the events' type if known, or to the onmessage event handler if no type-specific event handler was established.

HTTP is an extensible protocol that is easy to use. The client-server structure, combined with the ability to add headers, allows HTTP to advance along with the extended capabilities of the Web.

Though HTTP/2 adds some complexity by embedding HTTP messages in frames to improve performance, the basic structure of messages has stayed the same since HTTP/1.0. Session flow remains simple, allowing it to be investigated and debugged with a simple HTTP message monitor.

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HTTP is a protocol for fetching resources such as HTML documents. It is the foundation of any data exchange on the Web and it is a client-server protocol, which means requests are initiated by the recipient, usually the Web browser. A complete document is reconstructed from the different sub-documents fetched, for instance, text, layout description, images, videos, scripts, and more.

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IP stands for internet protocol. It is a protocol defined in the TCP/IP model used for sending the packets from source to destination. The main task of IP is to deliver the packets from source to the destination based on the IP addresses available in the packet headers. IP defines the packet structure that hides the data which is to be delivered as well as the addressing method that labels the datagram with a source and destination information.

Source: https://www.javatpoint.com/ip

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Here, IP stands for internet protocol. It is a protocol defined in the TCP/IP model used for sending the packets from source to destination. The main task of IP is to deliver the packets from source to the destination based on the IP addresses available in the packet headers. IP defines the packet structure that hides the data which is to be delivered as well as the addressing method that labels the datagram with a source and destination information.

An IP protocol provides the connectionless service, which is accompanied by two transport protocols, i.e., TCP/IP and UDP/IP, so internet protocol is also known as TCP/IP or UDP/IP.

The first version of IP (Internet Protocol) was IPv4. After IPv4, IPv6 came into the market, which has been increasingly used on the public internet since 2006.

History of Internet Protocol

The development of the protocol gets started in 1974 by Bob Kahn and Vint Cerf. It is used in conjunction with the Transmission Control Protocol (TCP), so they together named the TCP/IP.

The first major version of the internet protocol was IPv4, which was version 4. This protocol was officially declared in RFC 791 by the Internet Engineering Task Force (IETF) in 1981.

After IPv4, the second major version of the internet protocol was IPv6, which was version 6. It was officially declared by the IETF in 1998. The main reason behind the development of IPv6 was to replace IPv4. There is a big difference between IPv4 and IPv6 is that IPv4 uses 32 bits for addressing, while IPv6 uses 128 bits for addressing.

Function

The main function of the internet protocol is to provide addressing to the hosts, encapsulating the data into a packet structure, and routing the data from source to the destination across one or more IP networks. In order to achieve these functionalities, internet protocol provides two major things which are given below.

An internet protocol defines two things:

Format of IP packet

IP Addressing system

What is an IP packet?

Before an IP packet is sent over the network, two major components are added in an IP packet, i.e., header and a payload.

An IP header contains lots of information about the IP packet which includes:

Source IP address: The source is the one who is sending the data.

Destination IP address: The destination is a host that receives the data from the sender.

Header length

Packet length

TTL (Time to Live): The number of hops occurs before the packet gets discarded.

Transport protocol: The transport protocol used by the internet protocol, either it can be TCP or UDP.

There is a total of 14 fields exist in the IP header, and one of them is optional.

Payload: Payload is the data that is to be transported.

How does the IP routing perform?

IP routing is a process of determining the path for data so that it can travel from the source to the destination. As we know that the data is divided into multiple packets, and each packet will pass through a web of the router until it reaches the final destination. The path that the data packet follows is determined by the routing algorithm. The routing algorithm considers various factors like the size of the packet and its header to determine the efficient route for the data from the source to the destination. When the data packet reaches some router, then the source address and destination address are used with a routing table to determine the next hop's address. This process goes on until it reaches the destination. The data is divided into multiple packets so all the packets will travel individually to reach the destination.

For example, when an email is sent from the email server, then the TCP layer in this email server divides the data into multiple packets, provides numbering to these packets and transmits them to the IP layer. This IP layer further transmits the packet to the destination email server. On the side of the destination server, the IP layer transmits these data packets to the TCP layer, and the TCP layer recombines these data packets into the message. The message is sent to the email application.

What is IP Addressing?

An IP address is a unique identifier assigned to the computer which is connected to the internet. Each IP address consists of a series of characters like 192.168.1.2. Users cannot access the domain name of each website with the help of these characters, so DNS resolvers are used that convert the human-readable domain names into a series of characters. Each IP packet contains two addresses, i.e., the IP address of the device, which is sending the packet, and the IP address of the device which is receiving the packet.

Types of IP addresses

IPv4 addresses are divided into two categories:

Public address

Private address

Public address

The public address is also known as an external address as they are grouped under the WAN addresses. We can also define the public address as a way to communicate outside the network. This address is used to access the internet. The public address available on our computer provides the remote access to our computer. With the help of a public address, we can set up the home server to access the internet. This address is generally assigned by the ISP (Internet Service Provider).

Key points related to public address are:

The scope of the public address is global, which means that we can communicate outside the network.

This address is assigned by the ISP (Internet Service Provider).

It is not available at free of cost.

We can get the Public IP by typing on Google "What is my IP".

Private address

A private address is also known as an internal address, as it is grouped under the LAN addresses. It is used to communicate within the network. These addresses are not routed on the internet so that no traffic can come from the internet to this private address. The address space for the private address is allocated using InterNIC to create our own network. The private addresses are assigned to mainly those computers, printers, smartphones, which are kept inside the home or the computers that are kept within the organization. For example, a private address is assigned to the printer, which is kept inside our home, so that our family member can take out the print from the printer.

If the computer is assigned with a private address, then the devices available within the local network can view the computer through the private ip address. However, the devices available outside the local network cannot view the computer through the private IP address, but they can access the computer if they know the router's public address. To access the computer directly, NAT (Network Address Translator) is to be used.

Key points related to private address are:

Its scope is local, as we can communicate within the network only.

It is generally used for creating a local area network.

It is available at free of cost.

We can get to know the private IP address by simply typing the "ipconfig" on the command prompt.

# data[].attributes.attachment_link.description
Here, IP stands for internet protocol. It is a protocol defined in the TCP/IP model used for sending the packets from source to destination. The main task of IP is to deliver the packets from source to the destination based on the IP addresses available in the packet headers.

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SMTP (Simple Mail Transfer Protocol) is a TCP/IP protocol used in sending and receiving e-mail. However, since it is limited in its ability to queue messages at the receiving end, it is usually used with one of two other protocols, POP3 (Post Office Protocol) or IMAP (Internet Message Access Protocol), that let the user save messages in a server mailbox and download them periodically from the server. In other words, users typically use a program that uses SMTP for sending e-mail and either POP3 or IMAP for receiving e-mail.

Source: https://www.techtarget.com/whatis/definition/SMTP-Simple-Mail-Transfer-Protocol

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By

SMTP (Simple Mail Transfer Protocol) is a TCP/IP protocol used in sending and receiving e-mail. However, since it is limited in its ability to queue messages at the receiving end, it is usually used with one of two other protocols, POP3 (Post Office Protocol) or IMAP (Internet Message Access Protocol), that let the user save messages in a server mailbox and download them periodically from the server. In other words, users typically use a program that uses SMTP for sending e-mail and either POP3 or IMAP for receiving e-mail.

How SMTP works

SMTP works as a three-step process, using a client/server model. First, an e-mail server uses SMTP to send a message from an e-mail client, such as Outlook or Gmail, to an e-mail server. Second, the e-mail server uses SMTP as a relay service to send the e-mail to the receiving e-mail server. Third, the receiving server uses an e-mail client to download incoming mail via IMAP and place it in the inbox of the recipient.

SMTP vs. IMAP

Hosted on an SMTP server, SMTP is used to send, relay or forward messages from a mail client, but cannot receive messages.

On the other hand, IMAP is an e-mail protocol that deals with managing and retrieving e-mail messages. IMAP keeps an email on a server, and then synchronizes it across several devices. IMAP is used in receiving emails, not sending them.

When used together, SMTP and IMAP transmit email messages.

SMTP vs. HTTP APIs

SMTP has been used since 1982 and remains the most common e-mail protocol to send an e-mail message nearly four decades later. However, there has been a trend toward using cloud-based HTTP APIs to send and receive e-mail.

HTTP APIs offer two advantages: The communication between e-mail client and server (for example, when using mobile apps) is faster than SMTP because HTTP APIs require fewer back-and-forth commands to authenticate the sender and recipient. Additionally, APIs offer functionality that is not available using SMTP.

SMTP and Unix-based systems

On Unix-based systems, Sendmail remains the most widely used SMTP mail server for e-mail. Sendmail provides the-behind-the-scenes e-mail transport and is typically used with a separate user-friendly interface.

SMTP usually is implemented to operate over Internet port 25. An alternative to SMTP that is widely used in Europe is X.400/X.500. When it was created, X.400 was intended to serve as the primary international protocol. Among most users, X.400/X.500 has been eclipsed by SMTP, but it remains popular in the defense and telecommunications industries.

Continue Reading About SMTP (Simple Mail Transfer Protocol)

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What is SMTP (Simple Mail Transfer Protocol)? - Definition from WhatIs.com

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SMTP (Simple Mail Transfer Protocol) is a TCP/IP protocol used in sending and receiving e-mail. However, since it is limited in its ability to queue messages at the receiving end, it is usually used with one of two other protocols, POP3 or IMAP, that let

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The User Datagram Protocol, or UDP, is a communication protocol used across the Internet for especially time-sensitive transmissions such as video playback or DNS lookups. It speeds up communications by not formally establishing a connection before data is transferred. This allows data to be transferred very quickly, but it can also cause packets to become lost in transit — and create opportunities for exploitation in the form of DDoS attacks.

Source: https://www.cloudflare.com/learning/ddos/glossary/user-datagram-protocol-udp/

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Poner aqui una descripción.

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FTP means "File Transfer Protocol" and refers to a group of rules that govern how computers transfer files from one system to another over the internet. Businesses use FTP to send files between computers, while websites use FTP for the uploading and downloading of files from their website's servers.

FTP works by opening two connections that link the computers trying to communicate with each other. One connection is designated for the commands and replies that get sent between the two clients, and the other channel handles the transfer of data. During an FTP transmission, there are four commands used by the computers, servers, or proxy servers that are communicating. These are “send,” “get,” “change directory,” and “transfer.”

While transferring files, FTP uses three different modes: block, stream, and compressed. The stream mode enables FTP to manage information in a string of data without any boundaries between them. The block mode separates the data into blocks, and in the compress mode, FTP uses an algorithm called the Lempel-Ziv to compress the data.

Source: https://www.fortinet.com/resources/cyberglossary/file-transfer-protocol-ftp-meaning

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What is FTP (File Transfer Protocol)?

FTP (File Transfer Protocol) is a standard network protocol used for the transfer of files from one host to another over a TCP-based network, such as the Internet.

FTP works by opening two connections that link the computers trying to communicate with each other. One connection is designated for the commands and replies that get sent between the two clients, and the other channel handles the transfer of data. During an FTP transmission, there are four commands used by the computers, servers, or proxy servers that are communicating. These are "send," "get," "change directory," and "transfer."

While transferring files, FTP uses three different modes: block, stream, and compressed. The stream mode enables FTP to manage information in a string of data without any boundaries between them. The block mode separates the data into blocks, and in the compress mode, FTP uses an algorithm called the Lempel-Ziv to compress the data.

What is FTP Useful For?

One of the main reasons why modern businesses and individuals need FTP is its ability to perform large file size transfers. When sending a relatively small file, like a Word document, most methods will do, but with FTP, you can send hundreds of gigabytes at once and still get a smooth transmission.

The ability to send larger amounts of data, in turn, improves workflow. Because FTP allows you to send multiple files at once, you can select several and then send them all at the same time. Without FTP services, you may have to send them one by one, when you could be accomplishing other work.

For example, if you have to transfer a large collection of important documents from headquarters to a satellite office but have a meeting to attend in five minutes, you can use FTP to send them all at once. Even if it takes 15 minutes for the transfer to complete, FTP can handle it, freeing you up to attend the meeting.

How Many Types of FTP Are There?

While FTP can be used to accomplish several kinds of tasks, there are three primary categories of FTPs.

FTP Plain refers to normal FTP without encryption. By default, it uses port 21, and it is supported by the majority of web browsers.

FTPS refers to FTP Secure or FTP secure sockets layer (SSL) because this kind of FTP server uses SSL encryption, which is slightly different than traditional FTP. The primary difference is the security that comes with FTPS, which was the first type of encrypted FTP invented.

The "E" in FTPES means "explicit," making the acronym stand for File Transfer Protocol over explicit transport layer security (TLS)/SSL. This type of FTP begins like regular FTP, using port 21, but then special commands upgrade it to a TLS/SSL-encrypted transmission. Because it tends to work well with firewalls, some prefer to use FTPES over FTPS.

How to Use FTP

The three most common ways of using FTP include:

1. Via a web browser: With a web browser, you do not need any special software or a client to download files from servers that provide for FTP sites.

2. A general user interface (GUI) FTP client: These third-party applications enable users to connect and then send files over FTP.

3. Command-line FTP: Major operating systems come equipped with FTP client capabilities as a command line.

What is an FTP Port?

An FTP port is a communication endpoint and allows data transfer between a computer and a server. A computer's operating system only uses a specific number of ports, which are necessary for software to connect through a network. An FTP port is required for the client and server to quickly exchange files.

FTP stands for File Transfer Protocol, while SFTP refers to Secure Shell (SSH) File Transfer Protocol. This gives you file transfers that are secured via SSH, which provides full access to shell accounts. A shell account is one that sits on a remote server.

FTP is different from SFTP in that it does not give users a secure channel for transferring files. Also, FTP makes use of two channels for transferring data, but SFTP only uses a single channel. The inbound connections that each protocol uses are different as well. FTP defaults to port 21, but SFTP allows inbound communication on port 22.

The manner in which data is transferred is also significantly different. SFTP uses a tunneling method to transfer data. With the benefit of additional security, FTP, which is less secure, uses direct transfer.

Even though Hyper Text Transfer Protocol (HTTP) and FTP are similar in that they are application-layer protocols that enable you to send files between systems, there are some key differences. HTTP can support multiple sessions at the same time because it is a stateless protocol. This means it does not save the data used in a session to employ it in the next one.

FTP, on the other hand, is stateful, which means it collects data about the client and uses it in the next request the client makes. Because FTP performs this function, it is limited in the number of sessions it can support simultaneously. Regardless of the bandwidth of a network, HTTP has the potential to be a much more efficient method of data transmission.

Another key difference is that with FTP, there needs to be client authentication before information is transferred. With HTTP, no client authentication is needed. HTTP uses a well-known, common port, making it easy for firewalls to work with. In some cases, FTP can be more difficult for a firewall to manage.

In some ways, managed file transfer (MFT) is the new kid on the block when compared to FTP. FTP, while effective in many settings, was not designed to accommodate the complex threat landscape people are forced to deal with today. In fact, there has even been an official warning issued by the FBI regarding the potential pitfalls of using FTP-even that which is secured with SSL and SSH.

As the name suggests, managed file transfer comes with management and various compliance and security features. It is important for these to be in place, not just to make data transfer safer but to appease the authorities that require secure data transfer, particularly in companies that handle sensitive data such as patient medical records. Normal FTP leaves data transfers open to an eavesdropping attack or a banker Trojan, which targets financial institutions.

Even though you could manually program the security and management features necessary for safer FTP transmissions, MFT saves you the time and energy. If, for example, two people were using the Mist Browser to configure dapps on Ethereum, a hacker could intercept their communications before they reached the FTP port. The hacker could then sell what was intercepted to a competitor, who could use it to make a similar dapp and release it sooner, thus gaining a strategic advantage.

How To Change FTP Port Numbers

Application servers are assigned default port numbers, but if you want to change them, there are two ways you can do so:

1. Go to your FTP application's settings page, and change the port number from there.

2. Add the port number to the FTP server address. To do this, add a colon plus the new port number to the end of the FTP server address-before "/" if there is one. For example: ftp:/mydomain.com:####/-where each "#" is a digit.

Security Challenges of FTP

FTP was not designed to provide a secure tunnel through which information could travel. Hence, there is no encryption. If a hacker is able to intercept an FTP transmission, they would not have to muddle through encryption to view or make changes to the data usable. Even if you use FTP cloud storage, if the service provider has their system compromised, the data could be intercepted and exploited.

Therefore, data transmitted through FTP is a relatively slow-moving target for spoofing, sniffing, brute force, and other kinds of attacks. Through simple port scanning, a hacker could check an FTP transmission and attempt to exploit its vulnerabilities.

One of the primary vulnerabilities of FTP is its use of clear-text passwords, which are passwords that do not undergo an encryption process. In other words, "Jerry1992" looks exactly like "Jerry1992." In more secure protocols, an algorithm is used to mask the actual password. Therefore, "Jerry1992" may end up looking like "dj18387saksng8937d9d8d7s6a8d89." FTP does not secure passwords like this, making them easier to figure out by bad actors.

How Fortinet Can Help

FTP servers are frequently positioned within a demilitarized zone (DMZ). A DMZ is a network set up on the perimeter of an organization's local-area network (LAN) to protect it from potentially dangerous traffic. One of the best ways to protect FTP transmissions is by using FortiGate, the Fortinet next-generation firewall (NGFW). There are different ways of using FortiGate to safeguard your FTP-based communications.

You could use a single NGFW. With one NGFW in place, it can control and monitor traffic, and only approved data packets are allowed to enter the DMZ.

You can also use a dual firewall, which offers more safety than a single NGFW solution. With a dual firewall setup, you deploy two firewalls, one on either side of the DMZ. The first NGFW monitors and controls traffic attempting to enter the network from outside the DMZ. The second firewall provides a shield between the DMZ and your organization's internal network.

An attacker would have to find a way to compromise two NGFWs to gain access to your internal network. FortiGate gives you the ability to only grant specific users access to a web server that the DMZ protects. With this solution in place, you can handpick who is allowed to see and work with sensitive information. This provides sensitive data, even that which is sent using FTP, with an enhanced layer of security that would otherwise be unachievable.

Do you wish to protect your network, network traffic, and network-connected assets from cyber-attacks, unwanted access, and data loss? Check out our available network security services

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What is File Transfer Protocol (FTP) meaning | Fortinet

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Learn why you need File Transfer Protocol (FTP), how to use it, and the security challenges of FTP. FTP refers to a group of rules that govern how computers transfer files from one system to another over the internet.