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| Version | User | Scope of changes |
|---|---|---|
| Apr 22 2008, 10:38 AM EDT (current) | Dr.Disk | |
| Apr 22 2008, 10:18 AM EDT | Dr.Disk | 305 words added, 3 words deleted, 2 photos added |
Changes
Key: Additions Deletions
Target Points
Networking: - sharing of information and services
3 requirements:
Servers provide basic services:
Star topology supports both fiber and copper. Choosing a medium decision is based on cost of communication media, transmission speed and size of LAN (number of devices and distance between any two end nodes on the network.).
Basic Path - NIC => patch cable => wall jack => drop cable =>punch down block/patch panel => patch cable =>switch
Two basic star structures:
Flat
Cascaded/Hierarchical
Three basic benefits of the Star topology:
Identify key features of the Ethernet specifications
- Identify the features and benefits of a physical star topology
- Identify key features of the Ethernet specifications
- Identify key features of wireless technologies
- Identify key features of WAN technologies
Networking: - sharing of information and services
3 requirements:
- services - 2 devices with a need to share info
- media - a path for communication
- protocols/standards - the rules
Servers provide basic services:
- file
- messaging
- application
- database
Clients attach to these servers to gain access to services
Transport/Communication medium provides a path for data transfer (copper/fiber/radio)
Protocols - rules that allow information sent over the transport to be translated into meaningful data.
TCP/IP and ethernet are most common communication standards.
Tasks defined by protocols:
Purposes of a topology (the physical layout of cables and devices)
5 types of topologies are (bus, ring mesh, cellular and star {the most common topology})
A sample bus topology
NICs (Network Interface Cards) - change binary data of node to electrical or optical signals for transmission Transport/Communication medium provides a path for data transfer (copper/fiber/radio)
Protocols - rules that allow information sent over the transport to be translated into meaningful data.
TCP/IP and ethernet are most common communication standards.
Tasks defined by protocols:
- how bits are transmitted
- how cables are arranged
- number of devices per network
- when a device can transmit data
- how data is sent
- how devices communicate
- when messages are successfully transmitted/received
- how unlike OS communicate
Purposes of a topology (the physical layout of cables and devices)
- Transmit Bits
- Physical network structure
- Mechanical and electrical specs
- Encoding and timing rules for packet transmission
5 types of topologies are (bus, ring mesh, cellular and star {the most common topology})
Bus Topology - original ethernet standard
Nodes attached to a common backbone.
Signals generated by any device heard by all other devices.
Created two problems:
Collisions
Cable break would create noise and break communication among all devices
Nodes attached to a common backbone.
Signals generated by any device heard by all other devices.
Created two problems:
Collisions
Cable break would create noise and break communication among all devices
A sample bus topology
Features and benefits of a physical star topology
Cable concentration device (hub/switch) connecting clients and servers via drop cables.
Hub - receievs and passes signals - unable to decode signals and simply amplified signal before forwarding
Repeater - Used to amplify signal for greater distances and reliability
A hub that amplifies signals is a multi-port repeater.
Switches - more common today as the concentrator.
Data must pass through switch to reach devices directly or indirectly connected to the switch.
Hence, a switch is also a multi-port repeater
Cable concentration device (hub/switch) connecting clients and servers via drop cables.
Hub - receievs and passes signals - unable to decode signals and simply amplified signal before forwarding
Repeater - Used to amplify signal for greater distances and reliability
A hub that amplifies signals is a multi-port repeater.
Switches - more common today as the concentrator.
Data must pass through switch to reach devices directly or indirectly connected to the switch.
Hence, a switch is also a multi-port repeater
A Very Basic Star Topology
Star topology supports both fiber and copper. Choosing a medium decision is based on cost of communication media, transmission speed and size of LAN (number of devices and distance between any two end nodes on the network.).
Basic Path - NIC => patch cable => wall jack => drop cable =>punch down block/patch panel => patch cable =>switch
*Ethernet Standard *
Robust, high speed protocol capable of speeds up to 10 Gbps over physical star topology.
Fiber has extended distances once limited to hundreds of meters to tens of kilometers.
Specifications of Ethernet define certain limitations on cable types, cable lengths and the arrangement of switches.
Two basic star structures:
Flat
Cascaded/Hierarchical
Three basic benefits of the Star topology:
- ease of installation
- no disruptions when connecting or removing devices
- easy fault detection and component replacement
Identify key features of the Ethernet specifications
Identify key features of wireless technologies
Identify key features of WAN technologies
Identify key features of WAN technologies
