Introduction to Networking
Why use a Network?
Quite simply explained we use networks for communication between computers, sharing of data and peripherals. In the business world we use networks for ease of administration and to cut costs.
Sharing data example imagine an office with 5 secretaries working on 5 different computers, one requires a file from another computer in a non networked office this file would have to be written to a portable media then loaded onto the computer. In a networked office the file could be accessed via the network from a shared folder.
Sharing peripherals example the same office with 5 secretaries working on 5 different computers, in order to print their work each computer would need to have a printer attached. In a networked office you could have one shared printer, cutting costs.
What do you need?
A common language or protocol (TCP/IP IPX/SPX, APPLE TALK) is a convention or standard that controls or enables the connection, communication, and data transfer between two computing endpoints.
A common language or protocol (TCP/IP IPX/SPX, APPLE TALK) is a convention or standard that controls or enables the connection, communication, and data transfer between two computing endpoints.
Cabling BNC,Cat5, fibre optic
Hardware NIC(Network Interface Card), router, switch, hub, modem wireless
access point.
Network Service (DNS, WINS, DHCP).
Network Hardware
Network Interface Card
A network card, network adapter, network interface card or NIC is a piece of computer hardware designed to allow computers to communicate over a computer network. It has a MAC address. Every network card has a unique 48- bit serial number called a MAC address, which is written to ROM carried on the card. Every computer on a network must have a card with a unique MAC.address. The IEEE is responsible for assigning MAC addresses to the vendors of network interface cards. No two cards ever manufactured should share the same address.
Hubs
An Ethernet hub or concentrator is a device for connecting multiple twisted pair or fibre optic Ethernet devices together, making them act as a single segment. It works at the physical layer of the OSI model, repeating the signal received at one port out each of the other ports (but not the original one). The device is thus a form of multiport repeater. Ethernet hubs are also responsible for forwarding a jam signal to all ports if it detects a collision. Hubs also often come with a BNC and/or AUI connector to allow connection to legacy 10BASE2 or 10BASE5 network segments. The availability of low-priced Ethernet switches has largely rendered hubs obsolete but they are still seen in older installations and more specialist applications.
Switches
A network switch or switch for short is a networking device that performs transparent bridging (connection of multiple network segments with forwarding based on MAC addresses) at full wire speed in hardware. As a frame comes into a switch, the switch saves the originating MAC address and the originating (hardware) port in the switch’s MAC address table. This table often uses content-addressable memory, so it is sometimes called the “CAM table”. The switch then selectively transmits the frame from specific ports based on the frame’s destination MAC address and previous entries in the MAC address table. If the destination MAC address is unknown, for instance, a broadcast address or (for simpler switches) a multicast address, the switch simply transmits the frame out of all of the connected interfaces except the incoming port. If the destination MAC address is known, the frame is forwarded only to the corresponding port in the MAC address table.
Hubs VS Switches
A hub, or repeater, is a fairly unsophisticated broadcast device. Any packet entering any port is broadcast out on every port and thus hubs do not manage any of the traffic that comes through their ports. Since every packet is constantly being sent out through every port, this results in packet collisions, which greatly impedes the smooth flow of traffic. A switch isolates ports, meaning that every received packet is sent out only to the port on which the target may be found (assuming the proper port can be found; if it is not, then the switch will broadcast the packet to all ports except the port the request originated from). Since the switch intelligently sends packets only where they need to go the performance of the network can be greatly increased.
Routers
A router is a computer networking device that forwards data packets across a network toward their destinations, through a process known as routing. A router acts as a junction between two or more networks to transfer data packets among them. A router is different from a switch. A switch connects
devices to form a Local area network (LAN).
One easy illustration for the different functions of routers and switches is to think of switches as local streets, and the router as the junctions with the street signs. Each house on the local street has an address within a range on the street. In the same way, a switch connects various devices each with their own IP address(es) on a LAN. Routers connect networks together the way that on-ramps or major junctions connect streets to both main roads and motorways. The street signs at the junctions the (routing table) show which way the packets need to flow.
Wireless
Wireless Access Point (WAP) A wireless access point (AP) connects a group of wireless stations to an adjacent wired local area network (LAN). An access point is similar to an Ethernet hub, but instead of relaying LAN data only to other LAN stations, an access point can relay wireless data to all other compatible wireless devices as well as to a single (usually) connected LAN device, in most cases an Ethernet hub or switch, allowing wireless devices to communicate with any other device on the LAN.
Wireless Routers A wireless router integrates a wireless access point with an Ethernet switch and an Ethernet router. The integrated switch connects the integrated access point and the integrated Ethernet router internally, and allows for external wired Ethernet LAN devices to be connected as well as a (usually)
single WAN device such as a cable modem or DSL modem. A wireless router advantageously allows all three devices (mainly the access point and router) to be configured through one central configuration utility, usually through an integrated web server. However one disadvantage is that one may not decouple
the access point so that it may be used elsewhere.
#to_be_continue
Why use a Network?
Quite simply explained we use networks for communication between computers, sharing of data and peripherals. In the business world we use networks for ease of administration and to cut costs.
Sharing data example imagine an office with 5 secretaries working on 5 different computers, one requires a file from another computer in a non networked office this file would have to be written to a portable media then loaded onto the computer. In a networked office the file could be accessed via the network from a shared folder.
Sharing peripherals example the same office with 5 secretaries working on 5 different computers, in order to print their work each computer would need to have a printer attached. In a networked office you could have one shared printer, cutting costs.
What do you need?
A common language or protocol (TCP/IP IPX/SPX, APPLE TALK) is a convention or standard that controls or enables the connection, communication, and data transfer between two computing endpoints.
A common language or protocol (TCP/IP IPX/SPX, APPLE TALK) is a convention or standard that controls or enables the connection, communication, and data transfer between two computing endpoints.
Cabling BNC,Cat5, fibre optic
Hardware NIC(Network Interface Card), router, switch, hub, modem wireless
access point.
Network Service (DNS, WINS, DHCP).
Network Hardware
Network Interface Card
A network card, network adapter, network interface card or NIC is a piece of computer hardware designed to allow computers to communicate over a computer network. It has a MAC address. Every network card has a unique 48- bit serial number called a MAC address, which is written to ROM carried on the card. Every computer on a network must have a card with a unique MAC.address. The IEEE is responsible for assigning MAC addresses to the vendors of network interface cards. No two cards ever manufactured should share the same address.
Hubs
An Ethernet hub or concentrator is a device for connecting multiple twisted pair or fibre optic Ethernet devices together, making them act as a single segment. It works at the physical layer of the OSI model, repeating the signal received at one port out each of the other ports (but not the original one). The device is thus a form of multiport repeater. Ethernet hubs are also responsible for forwarding a jam signal to all ports if it detects a collision. Hubs also often come with a BNC and/or AUI connector to allow connection to legacy 10BASE2 or 10BASE5 network segments. The availability of low-priced Ethernet switches has largely rendered hubs obsolete but they are still seen in older installations and more specialist applications.
Switches
A network switch or switch for short is a networking device that performs transparent bridging (connection of multiple network segments with forwarding based on MAC addresses) at full wire speed in hardware. As a frame comes into a switch, the switch saves the originating MAC address and the originating (hardware) port in the switch’s MAC address table. This table often uses content-addressable memory, so it is sometimes called the “CAM table”. The switch then selectively transmits the frame from specific ports based on the frame’s destination MAC address and previous entries in the MAC address table. If the destination MAC address is unknown, for instance, a broadcast address or (for simpler switches) a multicast address, the switch simply transmits the frame out of all of the connected interfaces except the incoming port. If the destination MAC address is known, the frame is forwarded only to the corresponding port in the MAC address table.
Hubs VS Switches
A hub, or repeater, is a fairly unsophisticated broadcast device. Any packet entering any port is broadcast out on every port and thus hubs do not manage any of the traffic that comes through their ports. Since every packet is constantly being sent out through every port, this results in packet collisions, which greatly impedes the smooth flow of traffic. A switch isolates ports, meaning that every received packet is sent out only to the port on which the target may be found (assuming the proper port can be found; if it is not, then the switch will broadcast the packet to all ports except the port the request originated from). Since the switch intelligently sends packets only where they need to go the performance of the network can be greatly increased.
Routers
A router is a computer networking device that forwards data packets across a network toward their destinations, through a process known as routing. A router acts as a junction between two or more networks to transfer data packets among them. A router is different from a switch. A switch connects
devices to form a Local area network (LAN).
One easy illustration for the different functions of routers and switches is to think of switches as local streets, and the router as the junctions with the street signs. Each house on the local street has an address within a range on the street. In the same way, a switch connects various devices each with their own IP address(es) on a LAN. Routers connect networks together the way that on-ramps or major junctions connect streets to both main roads and motorways. The street signs at the junctions the (routing table) show which way the packets need to flow.
Wireless
Wireless Access Point (WAP) A wireless access point (AP) connects a group of wireless stations to an adjacent wired local area network (LAN). An access point is similar to an Ethernet hub, but instead of relaying LAN data only to other LAN stations, an access point can relay wireless data to all other compatible wireless devices as well as to a single (usually) connected LAN device, in most cases an Ethernet hub or switch, allowing wireless devices to communicate with any other device on the LAN.
Wireless Routers A wireless router integrates a wireless access point with an Ethernet switch and an Ethernet router. The integrated switch connects the integrated access point and the integrated Ethernet router internally, and allows for external wired Ethernet LAN devices to be connected as well as a (usually)
single WAN device such as a cable modem or DSL modem. A wireless router advantageously allows all three devices (mainly the access point and router) to be configured through one central configuration utility, usually through an integrated web server. However one disadvantage is that one may not decouple
the access point so that it may be used elsewhere.
#to_be_continue
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