1. Networking CIS 173 Week #3 OBJECTIVES Review Questions from Chapter #2 Lecture Chapter #3 Cabling

2. Hands On Project 2-1 Answer the questions and add questions to it

3. Questions? How many users attached? How many servers if any? What apps. will be run? Peer-to-Peer or Server based? Fault tolerance level required? Money available? Growth? E-Mail? Internet Access? Fax Capabilities?

4. Chapter #3 Cabling

5. Signals Payloads –Sequences of Electrical Signals –Sequences of Optical Signals Translates digital signal of computer into whatever form needed for OUTPUT –Binary –Analog etc... And translates INCOMING signals to digital form –Similar to a modem

6. Signal Transmission Way the signal is sent across the cable Two Ways –BASEBAND –BROADBAND

7. BASEBAND Digital encoding scheme (BINARY) –Single fixed frequency –PULSES of Electricity or Light –Entire Bandwidth is used for single data signal Decreases in strength as it travels Decreases in strength as it gets farther away from transmitter –MAX. CABLE SEGMENT USED TO KEEP SIGNAL INTELLIGABLE Signal Flow is BIDIRECTIONAL

8. BASEBAND Repeaters –Receive incoming signals and REFRESHES them –Then RETRANSMITS them on another cable segment –RESTORES SIGNAL TO ORIGINAL STRENGTH LIMITED as to how many repeaters can separate any two cable segments –Used to increase distance of LAN

9. BROADBAND ANALOG –A continuous range of values rather than –Electromagnetic or Optical WAVES FREQENCY –How many times AMPLITUDE –How big Usually higher bandwidths ONE WAY Communication NEED TWO CHANNELS –MID-SPLIT Broadband single cable divides bandwidth into two channels –Dual-Cable Broadband uses two cables ONE TRANSMITS ONE RECEIVES

10. BROADBAND Amplifiers –DETECT WEAK SIGNALS –STRENGTHENS THEM –REBROADCASTS THEM

11. General Cable Characteristics Bandwidth Rating –How many bits/bytes carried over a unit of time –Mbps (Megabits per second) Maximum Segment Length –Needed to to attenuation Weakening of signal –Value falls within a range where signals can be regenerated & retransmitted correctly This allows several segments to be used to lengthen your internetwork.

12. General Cable Characteristics Max. # of segments / Internetwork –Latency Time it takes for signal to travel from one end to the other Between any TWO network segments This keeps internetwork large if needed Max. # of devices / segment –Insertion Loss Each time a device is added it adds to the attenuation True Max.=Rated Max.-  (insertion losses)

13. General Cable Characteristics Interference Susceptibility –Other environmental signals Electromagnetic Interference –EMI Radio Frequency Interference –RFI »Transformers etc. –Four Levels None Low Moderate High

14. General Cable Characteristics Connection Hardware –Physical Connection from cable to hardware –Influences Type of hardware Costs Equipment needed to make the connection

15. General Cable Characteristics Cable Grade –Needed for Fire Codes In ceiling –CLADDING Combustibility of sheath Regular extension cords are very toxic and burn quick PLENUM –False ceiling used for heating & cooling PLENUM-RATED –Sheath is coated with Teflon –Low combustibility –Can be used in the open NOT IN CONDUIT

16. General Cable Characteristics Bend Radius –Can damage the cable –Can damage the signal More expensive cables –60 degrees in one foot –TP more flexible Material Costs –Determined by fire codes –Reuse cable if possible Found in PLENUM

17. General Cable Characteristics Installation Costs –Cable Plant ONLY Cable Connectors Wall Plates Patch Panels Punchdown Blocks Then you have to cost out and design the rest of the network.

18. Types of Cable Coaxial Twisted Pair (TP) –Shielded (STP) –Unshielded (UTP Fiber Optic High Speed Data Cable –Very Thick

19. COAXIAL COAX Inexpensive Easy to install Less susceptible to interference than TP more so than fiber optic Less susceptible to attenuation TP more so than fiber optic Single conductor Insulating layer SHIELDING –Braiding –Protective layer like CONDUIT Prevents –EMI –RFI Sheath –Outer Cover –Wrapper

20. Types of Coax THIN ETHERNET –THINNET –THINWIRE –CHEAPERNET 10BASE2 THICKNET –THICKNET –THICKWIRE 10BASE5

21. 10Base2 & 10Base5 10 –Total Bandwidth –10 Mbps BASE –The network uses BASEBAND signaling 2 or 5 –Rough MAX. SEGMENT LENGTH –In HUNDREDS of meters –200 meters –500 meters

22. Thinnet Connectors Must go from Machine to Machine BNC T-Connector –Connects DIRECTLY to NIC BNC Terminator BNC Cable Connector

23. Thicknet Connectors (Pg. 60) Use a BACKBONE and attach DROP CABLES Vampire Tap –To attach a device to a cable –Plugs into Transceiver Transceiver –Transmitter/Receiver –Plugs into a transceiver cable or drop cable Transceiver Cable / Drop Cable –From Transceiver to Hardware Up to 50 Feet Long / 15 Meters –Thickwire doesn’t have to snake from Machine to Machine because of this cable –Plugs into Attachment Unit Interface (AUI) Attachment Unit Interface –On the NIC –The NIC connection

24. TWISTED-PAIR CABLE CAT 1 to CAT 5 –Bandwidth Now coming out with CAT 6

25. Twisted -Pair Cable UTP –Unshielded Twisted Pair –Uses an RJ-45 Connector –One or more PAIRS of INSULATED wires IN and INSULATING SHEATH –10BaseT T is UTP –Max. Cable segment is 100 meters (328 feet) STP –Shielded Twisted Pair –Uses an RJ-45 Connector –Same as UTP except an EXTRA FOIL SHIELD between the wires and the insulating sheath Reduces Interference REDUCES “CROSSTALK” –INTERFERNCE FORM THE OTHER WIRES IN THE PAIRS

26. Twisted -Pair Cable Hardware associated with TP –PUNCHDOWN BLOCKs Vertical –PATCH PANELS Vertical –WALL PLATES How many Jacks do you NEED PC’s & Phone Lines Color of wall –JACK COUPLERS RJ-45 Terminated From Wall to Hardware

27. Twisted -Pair Cable Only NOT used in SIGNAL rich environments If distances preclude it.

28. Make Network practice disks

29. Next Week More Cables Make TP cables

30. Fiber Optic Cable HIGH BANDWIDTH LONG DISTANCES BETWEEN SEGMENTS Installation is DIFFICULT EXPENSIVE & Time Consuming Expensive Test Equipment needed –Proper Alignment of cable ends –For optical sensors & emitters Precisely Polished on cut end NOT FLEXIBLE

31. Two Types Fiber Optic Cable Single-Mode Cables –One glass fiber as core –Costs more –Laser-based emitters –Spans longer distance Multi-Mode Cables –Two or more glass fibers at core –Cost Less –Light Emitting Diodes (LED’s) –Shorter Distances

32. Fiber Optic Cable Use Pulses of Light –NOT electrical pulses IMMUNE TO INTERFERENCE –Because no electricity is passed through HIGHLY SECURE!!! –No possibility of Electrical Eavsdropping Less Attenuation Higher data-handling capacities –Higher bandwidth –High Speed –Longer Distances Core is GLASS FIBER –Light Conducting (ONE WAY) –Need TWO strands. –Not copper Glass Cladding –Not plastic Sheath is Kevlar –Not plastic

33. Four Types of Fiber Optic Connectors ST (Straight Tip) –Joins individual fibers at interconnects –Joins to the backbone –LOCKS on jack like BNC SC (Straight Connection) –PUSHES on –Easy to install –Used when splicing MIC (Medium Interface Connector) –Used in FDDI Fiber Distributed Data Interface (FDDI) SMA (Subminiature Type A) –Originally for Microwave use –Two Types: 905 –Straight FERRULE 906 –Stepped FERRULE with plastic sleeve –Precise alignments

34. Wireless Technology Interconnecting physically disjointed LAN’s Mobile users to stationary resources Creates temp. connections Back up EXTEND networks Span Roaming with machine MORE EXPENSIVE

35. Three Categories of Wireless Networks LAN’s –Connectivity for roving users Extended LAN’s –Extend distance Mobile Computing –Involves 3rd party to supply transmission & reception facilities to link mobile party

36. Wireless Hardware Most Require an ANTENNA & EMITTER On the wired network side you need an ACCESS POINT DEVICE –Includes an antenna & transmitter To send & receive traffic.

37. Wireless Transmission Signals are BROADCAST WAVES –Measured as FREQUENCY Affects amount of data & speed of data transmission Strength of transmission determines distance signal can travel & still be intelligible. –Measured as CYCLES PER SECOND Hz (Hertz)

38. Wireless Transmission Electromagnetic spectrum –Range of freqs. Governed by Government RADIO –10KHz - 1 GHz Microwave –1 GHz - 500 GHz Infrared –500 GHz - 1 THz

39. 4 Technologies for Transmitting & Receiving Infrared LAN –Infrared light beams –Line-of-Sight –Reflective Wireless –Scatter Infrared –Broadband Optical Telepoint –Subject to interference Laser-Based LAN –Requires clear line-of- sight –Not subject to interference Narrow-Band, Single-Freq. Radio LAN –Police & Fire –Requires FCC approval –Hard to get & Expensive –Walls & Barriers block signals –Easy to eavesdrop if within range Spread Spectrum LAN –Multiple Freqs. simultaneously –Improves reliability –Freq. Hopping Switches data on multiple freq. Regularly which makes it hard to eavesdrop Reduces interference

40. Make UTP RJ-45 Cables