A Gateway is communication device which is used for communication to a remote network or an autonomous system which is out of bounds for the host network nodes. Gateway work same as the entry and exit point of a network where all data routed inward or outward must first pass through and communicate with the gateway in order to use routing paths. Generally, a router is configured to work as a Gateway device in computer networks. In the Internet network for an enterprise a computer server acting as a Gateway node is often also acting as a proxy server and a firewall server. A Gateway is often associated with both a router which knows where to direct a given packet of data that arrives at the gateway, and a switch, which furnishes the actual path in and out of the gateway for a given packet.