A gateway is a computer on a network that provides an interface between two applications or networks using different protocols. It is also used to provide a connection to the Internet. Gateways in a network convert information from one protocol to another before being transmitted across the network. For example, if one computer on the Internet sends an email to another computer, a gateway converts the message from one protocol to another and sends it back.

This article discusses the need and function of gateways in computer networking.

How does the gateway work?

Computer gateways are servers with software installed to connect to networks and route data. A gateway node can be connected to a different router, or have a router connecting it to other networks or the Internet. Connections can be wired or wireless.

A computer server can act as a gateway node in any development team of any business organization and sometimes also act as a proxy server or firewall. A gateway of computers in the network inspects the data packets before passing them on to another network. It checks for compatibility between the two networks, then transforms the data packet to ensure it can be transmitted between the two networks.

Gateway nodes can also connect to servers for specific purposes, such as email, web hosting, and database storage. It can also be part of a wider network, such as the Internet. In this case, the gateway node will have its IP address, allowing it to route incoming traffic from different networks to its main interface, and on to the internet. However, this is one of many possible configurations of gateway nodes, and other configurations are possible.

The function of the gateway

A gateway in a network is a device that connects the Internet to a local area network. It can even be used as a bridge between two networks.

A network gateway has two functions.

• LAN to WAN function, connect LAN to Internet.
• WAN to LAN function, connect the Internet to a remote LAN.

When a packet arrives at the gateway, it first verifies the source information. Once the destination IP is verified, and any packet errors are checked, the data and protocol of the packet are transformed according to the requirements of the destination network. Finally, transmit the data packet to the target IP address by establishing a dedicated transmission channel.

Gateways in the network are also part of any telephone system, providing a bridge between the telephone network and the Internet. For example, want to set up a direct call for a customer. The real-time communications gateway will perform multiple tasks, automatically detecting the customer's current location and translating audio back and forth between different technologies.

The gateway filters data packets and isolates the corporate network from the public network. It is commonly used to isolate networks, ensuring the security of local and public networks. Gateways use a technique called NAT to provide the same protection as firewalls.

Types of Gateways in Computer Networks

There are two types of gateways in computer networks - bidirectional and unidirectional. The two types are briefly described below.

• Unidirectional Gateway: Data can only be transmitted in one direction. Changes can be made in the source endpoint and they will be replicated to all other target nodes or applications without making changes to themselves. These gateways act as archiving tools.

A one-way gateway consists of hardware and software. The technology allows data to flow from one source network to another, but cannot actually send any data back to the source network. Instead, gateway software emulates protocol servers and devices when replicating databases.

• Bidirectional Gateways: These gateways enable the bidirectional flow of data in the network. All tasks can be performed synchronously as it replicates the changes made on the source node to the target node, and vice versa. In short, a bidirectional gateway acts as a synchronization program or tool.

In a bidirectional gateway setup, changes made to the content of the source object server are transferred to the target object server, and the target object server replicates its alerts to the source object server.

An example of a gateway in a network

• IoT Gateway: It is the central hub between IoT devices and cloud servers. It typically allows bi-directional data flow, with incoming data flow being processed by the "cloud". IoT gateways are also known as control planes or smart gateways.
• Network Gateway: A network gateway is used to translate traffic across protocols. These translations make it possible to connect networks that use various protocols or data formats, and are translated inline by network gateways.

Network gateways are critical to connecting corporate LANs to the public Internet. Many businesses use different protocols than those used on the public Internet, but some of these communications may go to the Internet.

• Payment Gateway: A system that collects payment data from a client and sends it to an acquirer is called a payment gateway.
• Media Gateway: This is a device used in the main network of a telecom operator to convert and interconnect media streams using various wireless standards, codecs, communication protocols, and physical connections, so that the phone can use different systems on the network work correctly.
• Default Gateway: This is a node that establishes links across networks so that computers on different networks can communicate with each other. The "default" element of the phrase refers to the fact that it is usually the first and default route used.
• Email Security Gateway: It is an email security solution between the public Internet and corporate email servers. This location enables it to scan emails for malicious content before they reach the corporate network. However, the architecture of this gateway makes it unsuitable for protecting newer cloud-based email platforms.
• VoIP Trunk Gateway: A VoIP (Voice over Internet Protocol) trunk gateway is a device that connects PSTN devices to a VoIP network. It does this without an operator. These gateways provide a wide range of services, the most common of which is low-cost telephony.
• Web Application Firewalls: These firewalls provide a high level of security for network system connections. When a client seeks to access server resources such as web pages, files, and databases, the client initially establishes a connection with the proxy server, which then connects to the main server.

Summarize

Gateways in networks are often used in conjunction with routers. A router is a tiny computer/network device that connects to the internet. Routers come with specific software installed for home networking.

A router acts as a gateway in a network because it regulates the path data takes in and out. It does this by using built-in headers and forwarding tables to determine where packets should be routed. These packets contain emails, transactions, internet activity, and more.

A gateway is one of the many ways we transfer data over the internet. This gateway allows us to connect to many networks, send email, browse websites, shop online, and more. Gateways effortlessly provide us with the freedom, knowledge and convenience we enjoy online.

When individuals have hundreds of wearable and mobile devices that need to interact in and out of the home, it no longer makes sense to have a fixed router in the home to regulate traffic: all the devices will communicate with each other and directly with the Internet.

Frequently Asked Questions

Q: What is the difference between a gateway and a router?

Answer: A router is a device or piece of hardware that receives, processes, and routes data packets to other networks. The router detects the destination IP address of the packet and thus identifies the best path to send the packet with the help of headers and forwarding tables.

A gateway in a network is a device or piece of hardware that acts as a "gate" between networks. Therefore, it can also be described as a node that acts as an entry point for other nodes in the network. It is also responsible for allowing traffic to flow on the network. Because a gateway communicates over multiple protocols, its operation is much more complex than a switch or router.

Q: Is a gateway the same as a firewall?

A gateway is essentially a hardware or software interface that enables two networks to be connected. It effectively connects two different networks, allowing users to interact across multiple networks. A firewall is a security tool that tracks and regulates network traffic. It is at the heart of an organization's security architecture. Firewalls keep unauthorized users out of private networks connected to the Internet, especially intranets. It also monitors incoming and outgoing traffic against predefined criteria, protecting against suspicious traffic such as viruses and hackers.

Q: Which layer of equipment is the gateway?

Gateways are typically implemented at the network layer of the Open Systems Interconnection (OSI) architecture, but can be placed at any OSI layer. Virtual gateways or stand-alone gateways can be placed anywhere in the network where translation is required. They can be unidirectional (allowing data to travel in only one direction) or bidirectional (providing data flow in both directions).

Q: Does the gateway have an IP address?

The default gateway IP address is the router's private IP address. The router uses this address to interact with the local home network. In addition, the gateway is assigned two IP addresses. The first is an external IP address issued by your ISP (Internet Service Provider), while the second is an internal IP address that can only be accessed within your own network.