Wired and Wireless Networks

Chapter 12

Topics

• General Characteristics for:– Carrier, Speed, Frequency,

Transmission type, and Topology

• Factor that affect:– Range and speed– The appropriate tool for the job

Before You Install

• You need a clear picture of:– The current network configuration– How the network behaves– Look at:

• Configuration files• Error logs• Current Operating Systems

• You also need to understand the equipment you are installing

Standard Operating Procedures

• The company policy typically cover everything from sick-day accrual to how the computer systems are used.

• There may be policies regarding:– Internet access– Printing– Storage allocation– E-mail usage– User administration

Naming Conventions

• Include:– Servers– Printers– User accounts– Group accounts– Test and service accounts

Protocol Standards

• Choice of protocols vary:– IPX/SPX– TCP/IP

• Your primary choice will be TCP/IP

Workstation Configuration

• A narrow scope will help in setup and troubleshooting.

• Fewer images to deal with.• Also consider your equipment.

– Too many different brands and models also create problems

• Standardize:– CPU– Amount of RAM– Hard Drive size– NIC– Monitors

Environmental Issues

• Power– Over age– Underage– Quality

• ESD• EMI• RFI• Climate

Error Messages and Log Files

• Event Viewerin Vista

Event Viewer Win2003

Current Configuration and Baselines

• Microsoft offers the MBSA tool– Microsoft Baseline Security Anylizer– Can be downloaded from Microsoft at:

http://www.microsoft.com/technet/security/tools/mbsa2/default.mspx

– Read the Documentation

Wireless Agencies and Standards

Regulations

• Because WLANs transmit over radio frequencies, they’re regulated by the same types of laws used to govern things like AM/FM radios.

• The FCC has released three unlicensed bands for public use: 900MHz, 2.4GHz, and 5GHz.

Unlicensed Frequencies

Wireless LAN standards

• IEEE 802.11a• IEEE 802.11b• IEEE 802.11g• IEEE 802.11n• IEEE 802.11ac

Types of Wireless signals

• Infrared Networking• Bluetooth Networking• 802.11

• 802.11a 54Mbps 5GHz• 802.11b 11Mbps 2.4GHz• 802.11g 11 and 54Mbps• 802.11n 600Mbps 2.4 & 5GHz• 802.11ac 1Gbps (by 2015)

802.11

802.11 (cont.)

2.4 GHz band

• Channels 1, 6, and 11 are non-overlapping

802.11a

• UNII 5GHz band has 12 non-overlapping channels (U.S.).

802.11n

• 802.11n builds on previous 802.11 standards by adding Multiple-Input Multiple-Output (MIMO), which employs multiple transmitters and receiver antennas to increase data throughput. 802.

• 11n can have up to eight antennas, but most of today’s access points use four.

Compare Standards

Wireless Antenna Characteristics

Model Gain

Indoor Rangeat 1Mbps

Indoor Rangeat 11Mbps

Outdoor Rangeat 2Mbps

Outdoor Rangeat 11Mbps

AIR-ANT2410Y-R

10dBi 800ft 230ft Not Specified

Not Specified

AIR-ANT1728 5.2dBi 497ft 142ft Not Specified

Not Specified

AIR-ANT4941 2.2dBi 350ft 130ft Not Specified

Not Specified

AIR-ANT2506 5.2dBi Not Specified

Not Specified

5000ft 1580ft

AIR-ANT24120 12dBi Not Specified

Not Specified

24,288ft 7392ft

Wireless Network Installation

• Factors to consider:– Wireless LAN standards– Installation type– Signal degradation (Site Survey)

Wireless LAN Modulation Techniques

• DSSS– Direct-Sequence Spread Spectrum

• FHSS– Frequency-Hopping Spread Spectrum

• OFDM– Orthogonal Frequency Division Multiplexing

• Defined on pages 387-388

Wireless Networking

• Two main devices:– WAP

– Wireless NIC

Installation Type

• Two different modes– Ad-Hoc– Infrastructure

Ad-Hoc Mode

• Two computers connected via wireless connections.

Less than 90 – 100 m

Infrastructure Mode

• Requires a WAP

Infrastructure Mode

• Requires:– SSID– Security settings

• Mac filtering• SSID Broadcast• Encryption

• War Driving• Signal Degradation

– Distance– Walls– Protocols used– Interference

Configuration

• WAP• NIC

– You can use Windows built in wireless configurations or

– Software specific that come with your device

Security types include:

Workstation Configuration

• Windows NT – 2012• NetWare• UNIX/Linux• Macintosh

Copper Wire Network Installation Tools

• Wire Crimps

• Media Tester

• Punchdown tools

Media Testing Tools

• Wire Map Testers– Wire map testers detect transposed wires, opens

(broken or unconnected wires), and shorts (wires or pins improperly connected to each other)—all problems that can render a cable run inoperable.

– Enables installers, contractors and maintenance technicians to map, test and troubleshoot data and voice communication cable and coax runs.

Continuity Testers

• Like a wire map tester, a continuity tester consists of two separate units that you connect to each end of the cable to be tested. In many cases, the two units can snap together for storage and easy testing of patch cables.

Tone Generators

• This type of device consists of one unit that you connect to a cable with a standard jack, or to an individual wire with alligator clips.

• This unit transmits a signal over the cable or wire. The other unit is a pen like probe that emits an audible tone when touched to the other end of the cable or wire or even to its insulating sheath.

Optical Loss Test Set

Multifunction Cable Testers

• Most of these units perform the basic tests called for by the most commonly used standards—such as wire mapping, length, attenuation, and NEXT for copper cables—and optical power and signal loss for fiber-optic.

Punchdown Tool

• Essentially the tool punches down thewire into some kind of insulation displacement connector (IDC). IDCs make contact by cutting through, or displacing, the insulation around a single conductor inside a twisted-pair cable.

Summary

• Summary• Exam Essentials• Written Lab• Review Questions