Network Hardware

What is Ethernet?

• Ethernet is a set of standards for the infrastructure a network is built on
• Ethernet is often referred to as 802.3 (IEEE standard)
• Ethernet transmits data at 10MBps
• Ethernet uses CSMA/CD(Carrier Sense Multiple Access / Collision Detection)
• Fast Ethernet - 100 Mbps (and now even 1 GBps)
• alternatives to Ethernet are Token Ring and ARCNet

Network Topology

• bus - contains a single main communications pathway (backbone) with each device attached to the main cable(bus)through a transceiver or with a T-connector on a network interface card (NIC) (usually Ethernet)
• ring - uses a central control unit (Media Access Unit - MAU) with a ring circuit inside] (usually token ring)
• star - requires a central computer with everything connected to it
• hybrid

Network Cable

• thick coax / yellow hose / 10Base5 - requires transceivers and AUI adapters (limited to 500 meters per segment)
• thinnet / 10Base2 - requires BNC connectors (limited to 185 meters & no more than 30 computers per segment)
• unshielded twisted pair / UTP / 10BaseT / (CAT1-5) - requires a hub and RJ45 connectors (limited to 100 m per segment)
• fiber optic / 10BaseF - requires special network cards; used for long distances

Reading a Network Ad

• Look for differences in prices based on quantities and features
• Be prepared to call about prices
• Check shipping costs and returns policy
• Data Comm Warehouse