Week 3 - Network Mediums and Cabling (1).pptx

Part 1: Network Cables NTWK8021 – Network Planning What are Network Cables? • Network cables serve as the physical medium for transmitting data in computer networks • Operate at Layer 1: The Physical Layer of the OSI model Network Cable Types • In today’s lesson, we are going to discuss the bel...

Part 1: Network Cables NTWK8021 – Network Planning What are Network Cables? • Network cables serve as the physical medium for transmitting data in computer networks • Operate at Layer 1: The Physical Layer of the OSI model Network Cable Types • In today’s lesson, we are going to discuss the below network cables – Coaxial cable – Twisted pair cables (ethernet) – Fibre optic cables Coaxial Cable • Coaxial cable is an electrical cable widely used in various scenarios, including television, internet, and telecommunications • Commonly used by ISPs to provide network connectivity to Residential Customers Coaxial Cable Twisted-Pair Cables • Twisted-pair cable consists of multiple individually insulated wires that are twisted together in pairs. • Sometimes a metallic shield is placed around them; hence the name shielded twisted-pair (STP). • Cable without outer shielding is called unshielded twisted-pair (UTP), and it’s used in twisted-pair Ethernet (10Base-T, 100BaseTX, 1000Base-TX) networks. • So why are the wires in this cable type twisted? Because when electromagnetic signals are conducted on copper wires in close proximity—like inside a cable—it causes interference called crosstalk. Twisting two wires together as a pair minimizes interference and even protects against interference from outside sources. Unshielded Twisted-Pair This cable type is the most common today for the following reasons: • It’s cheaper than other types of cabling. • It’s easy to work with. • It allows faster transmission rates than previous cable types. • UTP cable is rated in these categories: – – – – – – – Cat1 Cat2 Cat3 Cat4 Cat5 Cat5e cat6 Common UTP Cable Categories and Speeds • Most networks these days will use Cat5e or Cat6 ethernet cables • Common speeds these cables can support are 100Mbps or 1Gbps • Please see Chapter 3 of the textbook for descriptions of the differences between each category Cat5e UTP Cable UTP Cable Connectors • There are two standard connectors you will see with Twisted pair cables RJ-45 and RJ-11 – Ethernet cables use the RJ-45 connector which has four pairs (eight wires) – Desk Phones and older devices use the RJ11 connector, which has four wires RJ Connectors RJ-45 Connector Typical Pin-Outs Fibre Optic Cable • Fibre optic cables transmit data using light pulses through thin glass or plastic strands • They offer high-speed data transmission and can support much longer distances than other mediums • Not affected by electromagnetic interference • Fibre optic cables are widely used in highbandwidth networks, internet backbones, and telecommunications Fibre Optic Cable Part 2: Ethernet Wiring Standards NTWK8021 – Network Planning Wiring Standards • Ethernet cabling is essential to understand, especially if you plan to work on any LAN. There are different types of wiring standards available: – – – – – T568A T568B Straight-through Crossover Rolled/rollover T568A and T568B • T568A and T568B are the two most common standards used for Ethernet cable termination • T568A is considered legacy, while T568B is used more often in homes and workplaces T568A and T568B Diagram Best Practices and Recommendations • Choose either T568A or T568B as the standard and be consistent throughout the network • Label cables and maintain documentation to ensure easy troubleshooting and to help with future network changes Straight-Through Cables • An ethernet cable that is most commonly used in a network for connecting clients to a network • Uses the same wiring on both ends of the cable. T568A-T568A, T568B-T568B • Connects Unlike devices together – Examples: PC-Switch, Switch-Router Straight-Through Cable Wiring Cross-Over Cables • An ethernet cable that’s primary goal is to connect similar devices – Examples PC-PC, Switch-Switch, PC-Router • Uses different wiring on both ends of the cable. T568A -T568B or T568B – T568A • Most commonly used to connect switches together Cross-Over Cable Wiring Roll-over Cables • Used for establishing console connections to the management interface of devices – Examples: Routers and Switches • Uses Serial DB9 on one end and RJ-45 on the other – Serial DB9 on the management PC – RJ-45 is on the device to be managed Roll-Over Cable Wiring