Networking Components Chad Benedict – LTEC

What is a Network HUB? A Network HUB is a common connection point for devices in a network. HUBs are commonly used as the easiest and least expensive way to connect segments of a LAN by using multiple ports. When a packet arrives at one port, it is copied to the other ports so that all segments of the LAN can see all packets. Unlike a network switch or router, a network hub has no routing tables or intelligence on where to send information and broadcasts all network data across each connection. 2 Prices range depending on the number of ports on the HUB. Example. 5 Port HUB = $10-30 If a message comes in for computer “A”, that message is sent out all the other ports, regardless of which one computer “A” is on. When computer “A” responds, its response also goes out to every other port on the hub

A network switch (also called switching hub, bridging hub, officially MAC bridge) is a computer networking device that connects devices together on a computer network, by using packet switching to receive, process and forward data to the destination device. A switch does essentially what a hub does, but more efficiently. By paying attention to the traffic that comes across it, it can “learn” where particular addresses are. People tend to benefit from a switch over a hub if their home network has four or more computers, or if they want to use their home network for applications that generate significant amounts of network traffic, like multiplayer games or heavy music file sharing. What is a Network Switch? 3 Prices range depending on the number of ports on the Switch. 5-8 Port Switch = $ Port Switch = $ Initially, a switch knows nothing and simply sends on incoming messages to all ports. Even accepting that first message, however, the switch has learned something – it knows on which connection the sender of the message is located. Thus, when machine “A” responds to the message, the switches only need to send that message out to the one connection. In addition to sending the response through to the originator, the switch has now learned something else – it now knows on which connection machine “A” is located. That means that subsequent messages destined for machine “A” need only be sent to that one port.

Routers come in all shapes and sizes – from the small, four-port broadband routers that are very popular right now to the large industrial strength devices that drive the internet itself. Routers should be used when the network needs to connect to the internet. A simple way to think of a router is as a computer that can be programmed to understand, possibly manipulate, and route the data that it’s being asked to handle. Many routers today are, in fact, little computers dedicated to the task of routing network traffic. As far as simple traffic routing is concerned, a router operates exactly as a switch, learning the location of the computers on its connections and routing traffic only to those computers. What is a Network Router? 4 Prices range depending on the number of ports on the Switch. 5-8 Port HUB = $ Port Switch = $ DHCP – Dynamic Host Configuration Protocol – is the way dynamic IP addresses are assigned. A device asks for an IP address to be assigned to it from “upstream” and a DHCP server responds with an IP address assignment. A router connected to your ISP-provided internet connection will typically ask your ISP’s server for an IP address; this will be your IP address on the internet. Your local computers, on the other hand, will ask the router for an IP address and these addresses are local to your network

A network bridge is a network device that connects multiple network segments or two segments of the same LAN that use the same protocol, such as Ethernet or Token-Ring. Bridges only forward packets between networks that are destined for the other network. Bridges are important in some networks because the networks are divided into many parts geographically remote from one another or the networks have different types of systems or devices. Something is required to join these networks so that they can become part of the whole network. A bridge may be used to connect a wireless network with a wired network. There are four types of network bridging technologies: simple bridging, multiport bridging, learning or transparent bridging, and source route bridging. What is a Network Bridge? 5 Prices range depending on the number of ports, the bandwidth, and whether it is wireless or wired. $20-500

A network gateway is an internetworking system capable of joining together two networks that use different base protocols. A network gateway can be implemented completely in software, completely in hardware, or as a combination of both. Depending on the types of protocols they support, network gateways can operate at any level of the OSI model. Because a network gateway, by definition, appears at the edge of a network, related capabilities like firewalls tend to be integrated with it. On home networks, a broadband router typically serves as the network gateway although ordinary computers can also be configured to perform equivalent functions. What is a Network Gateway? 6 Prices range depending on the number of ports, the bandwidth, and whether it is wireless or wired. $

A firewall is a network security system that controls the incoming and outgoing network traffic based on an applied rule set. Firewalls can be implemented in both hardware and software, or a combination of both. The firewall establishes a barrier between a trusted, secure internal network and another network (e.g., the Internet) that is assumed not to be secure and trusted. All messages entering or leaving the intranet pass through the firewall, which examines each message and blocks those that do not meet the specified security criteria. The Firewall may be a computer or server with firewall software, a network router, or a gateway. What is a Firewall? 7 Prices range vary greatly depending on the configuration of the network. Routers with built in Firewall range from $ A network may be configured to use NAT – Network Address Translation in order to act as a firewall. The router translates the IP addresses of packets that cross the internet/local network boundary. When computer “A” sends a packet out, the IP address that it’s “from” is that of computer “A” – in the example above. When the router passes that on to the internet, it replaces the local IP address with the internet IP address assigned by the ISP. It also keeps track, so that if a response comes back from somewhere on the internet, the router knows to do the translation in reverse – replace the internet IP address with the local IP address for machine “A” and then send that response packet on to machine “A”. Router used as a Firewall Computer or Server used as a Firewall

In a wireless local area network (WLAN), an access point is a station that transmits and receives data (sometimes referred to as a transceiver). An access point connects users to other users within the network and also can serve as the point of interconnection between the WLAN and a fixed wire network. Each access point can serve multiple users within a defined network area; as people move beyond the range of one access point, they are automatically handed over to the next one. A small WLAN may only require a single access point; the number required increases as a function of the number of network users and the physical size of the network. Access points don't have built-in technology for sharing Internet connections. To share an Internet connection, you must plug an access point into a router or a modem with a built-in router. What is a Wireless Access Point? 8 Prices range vary greatly depending on the configuration of the network. Wireless Access Points $20-200

Network Diagram with all components 9

Q & A 10 Qanda.png. [Online image]. Available at July 2014.