2.7 - Compare and contrast internet connection types, network types, and their features. Flashcards
Cable Modem
Broadband.
Transmission across multiple frequencies
Different traffic types.
Data on the “cable” network
DOCSIS (Data Over Cable Service Interface Specification).
High-speed networking
4 Mbits/s - 250 Mbits/s are common.
Gigabit speeds are possible
Multiple services - data, voice
ADSL
ADSL - Asymmetric Digital Subscriber Line.
Uses existing telephone lines.
Download speed is faster than upload speed (asymmetric).
~10,000 foot limitation from the central office (CO).
52 Mbit/s downstream, 16 Mbit/s upstream is common.
Faster speeds may be possible if closer to the CO.
Dialup
Network with voice telephone lines.
Analog lines with limited frequency response.
56 kbit/s modems.
Compression up to 320 kbit/s.
Relatively slow throughput.
Difficult to scale.
Legacy systems, network utility.
May be difficult to find a modem.
Fiber
Fiber optics to the home - high speed networking.
Converged services - Voice, Video, Data.
Hundreds of HD channels.
1 Gbit/sec Internet access.
1 Terabyte of cloud storage.
2 Terabyte DVR.
Satellite Networking
Communication to a satellite.
High cost relative to terrestrial networking.
50 Mbit/s down, 3 Mbit/s up are common.
Used typically:
Remote sites, difficult-to-network sites.
High latency - 250 ms up, 250 ms down
High frequencies - 2 GHz
Line of sight, rain fade
ISDN
Integrated Services Digital Network.
Commonly used as connectivity from the PSTN to large phone systems (PBX)
BRI - Basic Rate Interface (2B+D)
Two 64 kbit/s bearer (B) channels
One 16 kbit/s signalling (D) channel
PRI - Primary Rate Interface
Delivered over a T1 or E1
T1 - 23B + D
E1 - 30B + D + alarm channel
Cellular Networks
Mobile devices - “Cell” phones.
Separate land into “cells”.
Antenna coverages a cell with certain frequencies.
Tethering.
Turn your phone into a wireless router.
Mobile hotspot.
Standalone devices.
Line-of-sight service
Line-of-sight
Visual path between antennas - high frequencies.
Common in metropolitan areas.
Covers many homes simultaneously.
Also options for non-line-of-sight - lower frequencies.
WiMAX - Worldwide Interoperability for Microwave Access.
Wireless high-speed Internet access.
LAN
Local Area Network.
A building or group of buildings.
High-speed connectivity.
Ethernet and 802.11 wireless.
WAN
Wide Area Network.
Spanning the globe.
Generally connects LANs across a distance.
Generally much slower than the LAN.
Many different WAN technologies:
Point-to-point serial.
MPLS.
Terrestrial and non-terrestrial.
PAN
Personal Area Network.
Your own private network.
Bluetooth, IR, NFC.
Automobile.
Audio output.
Integrate with phone.
MAN
Metropolitan Area Network.
A network in your city.
Larger than a LAN, often smaller than a WAN.
Historically MAN-specific topologies.
Everyone’s moving to Metro Ethernet.
Common to see government ownership.
WMN
Wireless mesh network.
All devices connect together.
Self form - Connects to each other automatically.
Self heal - Reacts automatically to changes.
Many different network technologies:
802.11, Zigbee, Z-wave etc.
