Modern Telecom Gateways
The academic definition of Media Gateway is as a device, such as a circuit switch, IP gateway, or channel bank that converts data from the format required for one type of network to the format required for another.
Telecom networks, mainly voice communication networks use various components that connect your desk phone to the external world. Every generation of telecom standards or protocols are evolved independently and Gateways are required to communicate between different generations of technologies. They convert the format of a phone call to allow it to pass between new generation SIP network and an earlier generation of the public switched telephone network (PSTN), and allow users to bring their analog phones fully into Unified Communications environment. Gateways also offer a level of Security to the Telecommunications Network.
There are two broad categories of Communication Gateways :
VoIP Gateway :
A network device that converts voice and fax calls, in real time, between the public switched telephone network (PSTN) and an IP network. The primary functions of a VoIP gateway include voice and fax compression/decompression, packetization, call routing, and control signalling.
Media Gateway :
A media gateway is a translation device or service that converts media streams between disparate telecommunications technologies such as POTS, SS7, Next Generation Networks (2G, 2.5G and 3G radio access networks) or private branch exchange (PBX) systems.
Functions of Gateways :
In a communications network, a network node equipped for interfacing with another network that uses different protocols. For example:
Connect IP telephones to a legacy PBX
Integrate network-hosted applications with a PBX
Extend a PBX to branch offices
Integrate various voice, fax, and call processing capabilities into an enterprise LAN or WAN environment
A gateway may contain devices such as protocol translators, impedance matching devices, rate converters, fault isolators, or signal translators as necessary to provide system interoperability. It also requires the establishment of mutually acceptable administrative procedures between both networks.
When enterprises are ready to transition to a complete IP solution from a hybrid solution, the IP applications will continue to function seamlessly. When customers require higher density solutions, the solutions can be scaled easily with reduced equipment downtime.
Applications of Gateways :
Protocol Converter: Gateways, also called protocol converters, can operate at any network layer. The activities of a gateway are more complex than that of the router or switch as it communicates using more than one protocol.
Internet Gateway: Another term for "router," specifically when the router is in a local network, and its primary purpose is to forward packets to the Internet and receive packets from the Internet.
IOT Gateway: An Internet of Things (IoT) gateway is a physical device or software program that serves as the connection point between the cloud and controllers, sensors and intelligent devices. All data moving to the cloud, or vice versa goes through the gateway, which can be either a dedicated hardware appliance or software program. An IoT gateway may also be referred to as an intelligent gateway or a control tier.
Cloud Storage Gateway: A cloud storage gateway is a hardware- or software-based appliance located on the customer premises that serves as a bridge between local applications and remote cloud-based storage. The gateway can make cloud storage appear to be a NAS filer, a block storage array, a backup target or even an extension of the application itself. A cloud storage gateway provides basic protocol translation and simple connectivity to allow the incompatible technologies to communicate transparently.
Media gateways are critical components for enterprises choosing to integrate PSTN and IP networks. Using a turnkey solution such as a gateway appliance is a suitable way to quickly introduce IP endpoints and applications while protecting investment in legacy hardware. Many media gateway appliances are available today, and it is important to select the ones that are easiest to integrate and manage. Voracious consumer demand is stimulating many advances in commercial wireless communications technology, particularly cellular and cordless telephones.