Installing a Physical Network. Chapter 8

Transcription

1 Installing a Physical Network Chapter 8

2 Contents Recognize and describe the function of basic components in a structured cabling system Explain the process of installing structured cable Install a network interface card Perform basic troubleshooting on a structured cable network

3 Structured Cabling

4 Network Diagrams

5 Structured Cabling Structured cabling is a set of standards for cable installers to follow Defined by EIA/TIA

6 Cable Basics All new network technologies use UTP and a physical star topology

7 The Basic Star There s nothing preventing you from placing a hub in the middle of the office and running cables across the floor to all the PCs. But it does present issues in the real world Cables can be tripped over Cables can be damaged from stepping on them Interference may be present Limits your ability to make changes or to troubleshoot

8 Structured Cable Network Components Structured cabling requires An equipment room Horizontal cabling Work area

9 Equipment Room Cables run from the work area to a central equipment room Equipment Room

10 Horizontal Cabling Cabling from the PCs to the equipment room is called horizontal cabling A single piece of horizontal cabling is called run Horizontal cabling

11 Work Area The work area is simply the office where the PC is located Work area

12 Horizontal Cabling Details Usually CAT 5e or better UTP cable UTP cable has either a solid or stranded core Solid core conducts better but is stiffer and breaks easier Stranded core Solid core

13 Horizontal Cabling Details EIA/TIA specifies horizontal cabling use a solid core Cable installers recommend the highest grade cable you can afford using four pairs

14 Fire Ratings When a building catches on fire the insulation on cables that burns could cause noxious fumes and smoke Underwriter s Laboratories and the National Electrical Code have developed fire ratings Poly-Vinyl Chloride (PVC) creates smoke and noxious fumes when burned Plenum-rated cable creates much less smoke and fumes Most city ordinances require the use of plenum-rated cable

15 Choosing Horizontal Cabling Most network people use only CAT 5e or CAT 6 today Network installers may try to install a lower grade, so specify CAT 5e or CAT 6

16 Equipment Room All horizontal runs come together in the equipment room EIA/TIA s structured cabling standards define special components in the equipment room

17 Equipment Racks Equipment is mounted into equipment racks a central component of the equipment room 19 inches wide but vary in height

18 Rack Mountable Equipment Hubs Switches Servers Uninterruptible Power Supplies (UPSs) Rack mounted UPS

19 Patch Panels and Cables A patch panel is simply a box with a row of female connectors (ports) in the front and permanent connections in the back to which you connect horizontal cables Patch panels allow you to organize your cables

20 Patch Panels Label your patch panels so you can locate where the cables go UTP, STP, or fiber ports 8, 12, 24, 48 or more ports UTP comes with CAT ratings

21 Once the horizontal cabling is run and connected to the back of the patch panel, you use patch cables to connect to hubs or switches Patch cables are short 2 to 5 foot straightthrough UTP cables using a stranded wire core Patch Cables

22 Equipment rooms may be dedicated rooms, or part of a storage room, or a speciallymade cabinet with built-in equipment racks Equipment Room

23 Work Area The work area manifests itself in the wall outlet where horizontal cabling is terminated The wall outlet is a female jack where you would connect your PC using a patch cable

24 Wall Outlet Female RJ-45 jack should have the same CAT rating as your cabling It is a good idea to label your wall outlet to identify the position on the patch panel in the closet where the cable goes

25 Distances The horizontal cable may be at most 90 meters in length according to the EIA/TIA 568 specification The patch cable in the closet may be up to 6 meters in length The patch cable in the work area may be up to 3 meters in length Add it up 99 meters or about 100 meters (the maximum for UTP)

26 Work Area Issues Most network failures occur in the work area

27 Planning the Installation Professional installers assess your site and plan your installation in detail before a single piece of cable is pulled Can you stay within the 90 meter distance limit? How will you route the cable? What path should you take to the wall outlets?

28 Floor Plan Installers should always begin with a floor plan Shows the locations of potential closets, firewalls, and so forth If you don t have a floor plan, create one by poking around the ceilings, closets, and locations of rooms

29 Map the Runs A cable drop is the location where the cable comes out of the wall Map out where the cables will be run Talk to users and management about current and future needs The typical price for a network installation is around $150 per drop

30 Inside or Outside the Walls Do you want to run your cables inside or outside the walls Raceways adhere to the outside of the walls and make sense in some older buildings

31 Equipment Room Issues Distance Choose an equipment room location that is centrally located to keep maximum runs to 90 meters Power Generally put your equipment room outlets on their own dedicated circuit Dryness Choose a dry room with low humidity

32 Equipment Room Issues Coolness Equipment rooms get warm; make sure there is an air conditioning duct in the room

33 Equipment Room Issues Access Prevent unauthorized access the room should be locked Make it easy to get to the equipment to maintain and troubleshoot it An equipment room that has become a broom closet not good! A server wedged in the back of a closet and hard to get to not good!

34 Equipment Room Issues Expandability Will your equipment room be able to grow to accommodate a growing network? If another closet needs to be located in the next floor up, how easily can it be accessed from the current closet?

35 Equipment Racks Equipment racks Most equipment rooms use a floor-mounted equipment rack A smaller network may be able to use a wall-mounted short rack or just a wall-mounted patch panel

36 Installing the Cable Pulling cable requires two people to get the job done quickly Most pullers start from the equipment room Cable is drawn from a reel Professional cable pullers have many interesting tools to get the job done

37 Pulling Cable Old cable installations did not follow any standards leaving a mess Good cable management is important and must adhere today to local codes, EIA/TIA, and the National Electrical Code (NEC) rules Proper hooks and cable trays should be used

38 Pulling Cable Running the cable down through the wall to an outlet on the wall takes skill A hole is cut in the drywall using a stud finder A weight on the end of a nylon string is dropped through the wall down to the opening The network cable is tied to the nylon rope and then pulled down

39 Pulling Cable through the Wall An outlet box or low-voltage mounting bracket is then installed in the wall The cable is then terminated on the back of the jack A faceplate covers the front of the mounting bracket

40 Equipment Room Cables Many cables coming from work areas must be consolidated in the equipment room Special cable guides will help to bring the cables down to the equipment rack

41 Making Connections The cable then needs to be connected at both ends On the jack in the work area On the back of the patch panel in the closet The cables should be documented and labeled Every connection should be tested

42 Connecting the Work Area Attaching a jack to a wire Fitting the jack into a faceplate Tool used to make a 110- punchdown - the most common

43 Connecting the Patch Panels It is important to use proper cable management in the closet Plastic D-rings guide patch cables neatly along the sides and front of the patch panel Finger boxes are used to run individual cables

44 Connecting the Patch Panels Poor cable management Good cable management

45 Connecting the Patch Panels Organize the patch panel based on your network Either based on the physical layout of the network Or based on user groups

46 Labeling the Cable EIA/TIA defined the 606 labeling scheme Design a labeling scheme that matches your network s organization Label the outlet in the work area and the jack on the patch panel with the same number Color coding may be desirable

47 Labeling Well organized patch panels Labels on the patch panel and outlet match

48 Testing Cable Runs Professional cable installers run advanced tests on the cabling For example, near-end crosstalk and attenuation-tocrosstalk ratio Most network administrators and technicians only do minor testing with simple cable testers

49 Testing Cable Runs How long is the cable? Are any of the wires broken? If there is a break, where is it? Are any of the wires shorted together? An any of the wires in the wrong order (split or crossed pairs)? Is there electrical or radio interference?

50 Simple cable testers cost under $100 and only test for breaks in the wire by testing continuity Simple Cable Testers

51 Time Domain Reflectometer A medium priced cable tester (around $400+) can determine the length of the cable and where a break is located Called a Time Domain Reflectometer (TDR)

52 Advanced cable testers cost over $1000 Tests the electrical characteristics of the cable May generate a printed report May draw a diagram of the network including MAC addresses, IP addresses, and even operating systems for each computer Called media certifier tools Advanced Cable Testers

53 Beyond the Basic Star

54 Adding Hubs The network may be expanded by adding additional hubs that are then connected together As more nodes are added to the network traffic increases Hubs will extend the size of the collision domain Network performance will suffer

55 Switched Networks Hubs send the frames received on one port out all the other ports Switches send a frame received on one port only out the destination port conserving lots of bandwidth Hubs may simply be replaced with switches to greatly increase performance

56 Hubs and Switches Switches used to be far more expensive than hubs, but today they are about the same price Switches have become the standard network appliance replacing hubs Switches and hubs look alike One is a hub one is a switch

57 Switches A network with three switches installed instead of hubs

58 Multispeed Networks Faster technology isn t always the best It costs more and rewiring may be necessary The increased speed may not be needed Multispeed switches have some ports that run at one speed and others that run at a higher speed Some switches have all ports that may run at different speeds the ports are autodetecting and will sense what speed they need to run

59 Multispeed Switches Segments with servers attached or segments that connect with other parts of the network (called the backbone) may need higher speeds than other segments High-speed ports Multispeed ports lit up on a switch

60 Multiple Floors & Buildings Generally, networks use one equipment room per floor provided the cabling runs do not exceed the 90 meter limit If an office uses more than one floor, then you ll have multiple networks on multiple floors Backbone segments tie the networks together Larger networks require more servers, which are often grouped together in a single computer room

61 EIA/TIA Standards EIA/TIA 568 standards address cabling configuration and performance specifications EIA/TIA 569 standards address cable pathways and installation areas involving multiple equipment rooms, floors, and buildings Equipment room Horizontal cabling Work areas Backbone Building entrance Telecommunications closets

62 When a network is split into multiple floors or buildings, they are interconnected with highspeed backbone segments EIA/TIA recommends UTP or fiber optic for backbone segments Backbone cabling is called vertical cabling or risers Fiber optic cabling is recommended between buildings Backbones

63 Building Entrances The building entrance is where all the cables from the outside come into a building Telephone lines Cables from other buildings

64 NICs

65 NICs Network Interface Cards (NICs) are a common component in PCs today They are used to connect to a network A NIC needs to meet three criteria Technology such as Ethernet, Token Ring, or FDDI Speed such as 10 Mbps, 100 Mbps, or 1000 Mbps Type of bus such as ISA or PCI

66 Ethernet NICs 10Base5 10Base5, or Thicknet, NICs use a female, 15- pin DB connector Called Digital-Intel- Xerox (DIX) connector Drop cable runs from the DIX connector on the NIC to the Attachment Unit Interface (AUI) or transceiver

67 10Base2 or Thinnet NICs use a BNC connector that attaches via a T- connector Ethernet NICs 10Base2

68 Ethernet NICs 10BaseT 10BaseT, 100BaseT, and Gigabit Ethernet NICs all use RJ-45 connectors The cable runs from the NIC to a hub or switch

69 Ethernet NICs Fiber Optic Fiber optic NICs use either SC or ST connections An ST connector is shown in the figure

70 Token Ring NICs use either the older and rarer female DB-9 connector or the newer RJ-45 connector Token Ring NICs

71 Know Your NICs How do you know if a NIC is Ethernet or Token Ring if they both have RJ-45 connectors? What speed does the NIC run at? What software driver do I use? These questions can be answered by finding the model number which is usually printed on the card somewhere, or you should label it in the beginning

72 Installing NICs Installing a NIC involves 3 steps 1. Physically install the card in the PC 2. Assign unused system resources to the NIC using Plug and Play or manually 3. Install the proper drivers

73 Buying NICs It s better to stick with the name brands like 3Com or Intel Multispeed cards are usually better Try to stick with the same model Many companies standardize on which NICs to buy

74 Physical Connections Physically inserting the NIC into the PC is straight forward Make sure the NIC is for the proper expansion slot type The most common is Peripheral Component Interconnect (PCI) PCI-X is a faster slot used for Gigabit Ethernet NICs USB connections may be used but are slower PCMCIA or PC Card connections are seen on laptops PCI USB

75 Drivers Most NICs are plug and play and install easier in Windows systems However, Windows will most likely choose its own driver that is outdated It is better to install the driver that came with the NIC, and even better to download and install the latest driver off the Internet

76 Link Lights Most NICs have lights (really Light Emitting Diodes or LEDs) A link light tells you the NIC is connected to a hub or switch There s also a light on the hub or switch

77 Activity Lights and More The activity light on a NIC will flicker when there is network activity Multispeed NICS may also contain speed lights Older NICs may contain collision lights

78 Fiber Optic NICs Fiber optic NICS rarely have lights Most problems are traced to the ST or SC connection on the NIC An optical tester will allow you to test the connections

79 Direct Cable Connections Recent versions of Windows include software that enables direct serial-to-serial, parallel-toparallel, or infrared-to-infrared port connections Serial port connections require a null-modem cable Parallel port connections use a IEEE 1284-rated bidirectional parallel cable These connections are only good to connect two PCs together

80 Diagnostics and Repair of Physical Cabling

81 Diagnosing Physical Problems Most network problems are layer 1, or Physical layer, issues These manifest themselves as a device not showing up in My Network Places or server not found errors However, if you can do one network task (such as browse the Internet) but can t do another (like check ), then it is a software issue

82 Check Your Lights Check your link lights if they are not on then you have a cable issue A bad connection or maybe the wall outlet is bad or turned off at the closet The System Tray icon may indicate Network cable unplugged The horizontal cabling may be at fault If other users in the area also have a problem, then the issue may be the switch or hub

83 Check the NIC A bad NIC could also cause a problem with network connection Verify the NIC is working in Device Manager Run the NIC s diagnostic software if available A loopback test sends data out of the NIC to see if it comes back

84 Cable Testing Horizontal cable may be tested with a mid-range tester with TDR If the horizontal cable is bad, then it is best to replace the entire cable

85 Toner If cables aren t properly labeled, then they may need to be traced Use a toner to trace cables Uses a tone generator that connects to the cable and sends an electrical signal along the wire A tone probe makes a sound when placed near the right cable at the other end Toners are rather inexpensive Sometimes called by the brand name Fox and Hound