The document outlines LAN fundamentals, detailing various network models such as shared processing, peer-to-peer, and client-server architectures. It discusses the components required for managing LANs, such as file servers, application software, and network interface cards, along with RAID configurations for server storage. Additionally, it covers network topologies, access types, cable types, and the OSI model, providing a comprehensive overview of networking principles and practices.

1. LAN FundamentalsLAN Fundamentals
ETT 592
LAN Administration

2. Network ModelsNetwork Models
• Shared Processing
• Distributed Processing
– Peer to Peer
– Client Server

3. Shared ProcessingShared Processing
• Mainframe/Unix/Windows Terminal
Server environment
• All users share the same processor
• Users connect via “terminal emulation”

4. Peer to PeerPeer to Peer
• EASY!!!!
• CHEAP!!!!!
• Allows File and
Peripheral Sharing
• No centralized
control
• Generally insecure
• Unreliable

5. Client ServerClient Server
• Centralized
Management
• High Security
• Reduced client
management
• Easy backup
• Scalability
• Higher hardware
cost (dedicated
server)
• Server is failure
point
• More difficult to
manage

6. LAN ComponentsLAN Components
• File Server
• Application Software
• Workstations / Client OS
• NICs
• Shared Peripherals
• Data Files
• NOS

7. File ServerFile Server
• Central system
• Controls authentication
• Provides management of resources and
peripherals
• Often multi-processor
• Significant HD capacity
• BIG Box
• Becomes the weakest link

8. Application SoftwareApplication Software
• Programs that perform tasks
– Office Suites
– Database applications

9. WorkstationWorkstation
• Provide connection to network
• May or may not have HD
• May or may not be “dumb terminals”
• Can be running a variety of OS’s
depending on network capabilities

10. Workstation OSWorkstation OS
• Singletasking vs. Multitasking
– Cooperative (like kids sharing)
– Preemptive (like kids sharing with
supervision)
• Single User vs. Multi User
• Network protocol support

11. NICsNICs
• Network Interface Cards
• Allow physical connection between
network and the computer
• Manufactured by MANY companies.
– Buy from a major vendor
– Try to standardize

12. Data FilesData Files
• The most significant reason we network
today
• Provides shared, controlled access to
resources
• Provides centralized backup of
resources

13. Server StorageServer Storage
• HD capacity
• MTBF
• RAID 0, 1, 5

14. So What is RAID ???So What is RAID ???
• Redundant Array of Inexpensive Disks
• Can be done through OS or using
special SCSI controller cards

15. RAID 0RAID 0
• Disk Striping w/o parity
• Data written to multiple disks
• No increase in security
• Great Increase in I/O

16. RAID 1RAID 1
• Disk Mirroring / Duplexing
• Mirroring
– Two drives, single controller
– Redundancy, no I/O benefit
• Duplexing
– Two drives, two controllers
– Redundancy, I/O read benefit
• Storage capacity ½ of drive space

17. RAID 5RAID 5
• Disk Striping with Parity
• Data and parity blocks spread across all
drives
• Writes may be a bit slower
• Reads are faster
• Get redundancy
• Storage capacity is #drives-1

18. Shared PeripheralsShared Peripherals
• Printers
• Fax Servers

19. NOSNOS
• Network Operating Systems
• Windows NT
• Windows 2000
• Windows XP
• Unix / Linux
• Mac OS X

20. Hot SwapHot Swap
• Ability to replace parts while system is
running
– Power supplies
– HD

21. The weakest linkThe weakest link
• Server failure or downtime leads to
productivity loss
– Clustering prevents this
• Server failure leads to inability to authenticate
– PDC and BDC
• File retrieval is often slower
– Data files compared to application software
• Security Problems

22. The weakest link (cont)The weakest link (cont)
• Power Problems
– Redundant power supplies
– UPS
– Generators

23. How are networks builtHow are networks built
• Several components that must first be
considered.

24. Network TopologiesNetwork Topologies
• Bus
• Star
• Ring
• Mesh

25. Access TypesAccess Types
• Contention Based
– CSMA/CD
• Deterministic
– Token Passing

26. Cable TypesCable Types
• Coax
– RG58
• UTP
– CAT3
– CAT5
– CAT6e
• Fiber Optic

27. Network TypesNetwork Types
• Ethernet
– 10Base-2
– 10Base-T
– 100Base-T
• Token Ring
– Standard Token Ring
– FDDI

28. 10Base-210Base-2
• Bus Configuration
• RG58 wire with 50ohm terminator

29. 10Base-210Base-2
• Maximum Segment Distance 185m
(607 ft)
• Maximum network length 925m(3,035
ft)

30. 10Base-T/ 10Base-10010Base-T/ 10Base-100
• Ethernet / Star configuration
• Category 3 UTP=10mbs
• Category 5 UTP=100mbs

31. 10Base-T/ 10Base-10010Base-T/ 10Base-100
• Number of stations set by concentrator
• 1,024 stations per network
• 100 m to concentrator (328 ft)

32. Token RingToken Ring
• Token Passing Scheme
• Systems are connected to MAU
• Operate at 4 or 16mb
• Now use “Early Token Release”
• Tend to handle network load better

33. FDDI (Fiber DistributedFDDI (Fiber Distributed
Data Interface)Data Interface)
• Token passing scheme
• Dual counter rotating rings
• Fiber optic cable
• Class A connections are fault tolerant
• Class B connections are not fault
tolerant

34. How do the parts workHow do the parts work
togethertogether
• OSI Model is the theoretical basis
• No one adheres exactly to the model,
but everyone understands what it
means.

35. OSI ModelOSI Model
http://webopedia.internet.com/quick_ref/OSI_Layers.html

36. Physical LayerPhysical Layer
• Cabling, Topology
• Electrical Communications Stuff
• Cable and how it connects to the card

37. Data LinkData Link
• Organizes frames into structured data
packets
• 802.3 (CSMA/CD Ethernet)
• 802.5 (Token Ring)
• 802.11 (Wireless)

38. Network LayerNetwork Layer
• Responsible for routing data in
subnetted network
– If a transport protocol doesn’t support this
layer it is unroutable
• IP address converted to/from MAC
Address

39. Transport LayerTransport Layer
• Makes sure data gets from one point to
another
• Error Detection and recovery

40. Session LayerSession Layer
• Logical connection between network
devices

41. Presentation LayerPresentation Layer
• Translates data from application layer
to transmission format
• Encoding/Decoding
• ASCII, .DOC, .MPG, .JPG

42. Application LayerApplication Layer
• End User Software
• Email, File Transfer, Word,

43. How to rememberHow to remember
• Application
• Presentation
• Session
• Transport
• Network
• Data Link
• Physical
Please Do Not Throw Sausage Pizza Away

44. Network GearNetwork Gear
• Hubs ( a splitter )
– OSI layer 1 (Physical)
• Switches ( an intelligent splitter )
– OSI layer 2 (Data Link)
• MAUs ( a hub for a token ring network )
– OSI layer 1 (Physical)
• Routers (moves data between networks and
subnets )
– OSI layer 3 (Network)

45. IP AddressingIP Addressing
• Address Classifications
• Subnetting

46. IP Address ClassesIP Address Classes
Class Range # Networks Hosts/
Network
A 1-126 126 16,777,214
B 128-191.255 16,384 65,534
C 192.0.0-
225.255.255
2,097,152 254

47. So you want an addressSo you want an address
• Class A addresses are all gone
• Class B addresses are basically gone
• Class C addresses are available

48. Reserved AddressesReserved Addresses
• Class A 10.0.0.0-10.255.255.255
• Class B 172.16.0.0 – 172.31.255.255
• Class C 192.168.0.0 – 192.168.255.255
• Loop Back 127.0.0.1
• Reserved addresses are NEVER routed

49. What’s a subnet?What’s a subnet?
• Logical organization of computers
• A way to reduce network traffic
• A way to efficiently use assigned
addresses

50. Getting an IP addressGetting an IP address
• Hard Coding
– Manual Entry of
• DNS Servers (Domain Name Services)
• Gateways (Routers)
• IP Address
• DHCP
– Dynamic Host Control Protocol

51. IP ConfigurationIP Configuration
ExampleExample