LAN Admn
Review
Introduction
• What are the major groups of LAN Design
topics we need to consider?
– Topology
– NOS’s
– Equipment
– Media
– Protocols
Topologies
• Star
• Bus
• Ring
• Mesh
Star
• Center point of concentration with
connection points radiating from the center
Bus
• All computers connected to a single
backbone
Ring
• All computers connected to a single
backbone and the first is connected to the
last
Mesh
• All computers are connected to all other
computers
NOS’s
• Software to support network services
including
– Files
– Printing
– Applications
Media
• Bound
• Unbound
Unbound media
• Wireless
– 802.11a
– 802.11b
– 802.11g
Wireless specs
• 802.11a – 5.4 Ghz, 54 Mbps
• 802.11b – 2.4 Ghz, 11 Mbps
• 802.11g – 2.4 Ghz, 54 Mbps
• *802.11n – potentially 5.4 Ghz, 108 Mbps
Bound
• Copper
• Fiber (glass, or plastic)
Copper
• Coax
• Twisted Pair
Coax
• Center copper core
• Cladding
• Wire mesh
• Jacket
• Connector
– BNC connector – twist lock
• Terminated with 75 ohm terminator
Twisted Pair
• Unshielded
• Shielded
Shielded
• 22 or 24 AWG copper core wire
• Plastic insulator around each wire
• Pairs are twisted together as is the bundle of pairs
• Either a lightweight foil jacket around pairs
• Or Copper braiding
• Then the final jacket
• Must be grounded
• Connector: RJ-45
Unshielded
• 22 or 24 AWG copper core wire
• Plastic insulator
• Pairs are twisted as well as bundle of pairs
• Jacket
• Connector: RJ-45
Fiber
• Multimode
• Singlemode
Multimode
• Glass core
– 62.5 (1 = 1 x 10-6m)
• Cladding
• Buffering
• Jacket (Kevlar (outside) or Teflon (inside))
• Multiple light sources
• Shorter transmission distance
• LED light sources
Single mode
• Glass core
– 8 - 10
• Cladding
• Buffering
• Jacket (same as above)
• Single light source
• Longer transmission distance
• Laser light source
Equipment
• NIC • Server
• Workstations • Gateway
• Hub • Repeater
• Router • Bridge
• Switches • Media Converter
• Brouter • Terminators
Repeater
• Layer 1 device
• Repeats, regenerates and retimes networks
• Extends networks
• Topology
– Bus topology
Hub
• Layer 1 device
• Multiport repeater
• Topology
– Star topology
Media Converter
• Layer 1 device
• Simply converts from one media type to
another
– TP to Coax
– Coax to Fiber
– Fiber to TP
• Repeats signals
Bridge
• Layer 2 device
• Segments networks
• Filter packets
– Using MAC address
– Builds MAC Tables
• Topology
– Bus
Switch
• Layer 2 device
• Multiport bridge
• Topology
– Star
NIC
• Layer 2 device
• Provides an interface between network and
the computer
• Has the MAC address (the reason it’s a
layer 2 device) burned in
Router
• Layer 3 device
• Peforms path determination
• Works with logical addresses
Gateways
• Connects two dissimilar architectures
– SNA to Ethernet
– Token Ring to Ethernet etc.
All layers
• PCs
• Servers
Protocols
• TCP/IP
• IPX/SPX
• AppleTalk
• NetBEUI
TCP/IP
• Is a logical addressing protocol stack
• Works at layers 3 and 4
• IP – layer 3
• TCP – layer 4
• TCP is connection oriented
• IP is connectionless
• NetWare 3.x doesn’t use TCP/IP as it’s primary
protcol
• NetWare 5.x and above do
IPX/SPX
• It’s a logical addressing protocol stack
• Works at layers 3 and 4
• IPX – layer 3
• SPX – layer 4
• SPX is connection oriented
• IPX is connectionless
• NetWare 3.x uses IPX/SPX as it’s primary
protocol
• NetWare 5.x and above don’t