Demo Apple`s iPad Demo USB WiFi with Antenna

Demo Apple`s iPad Demo USB WiFi with Antenna
Telecommunication
Systems in Management
Topics
Bus Topologies and Ethernet
There are three
kinds of death in
this world. There's
heart death,
there's brain
death, and there's
being off the
network.
- Guy Almes
iPad
Memory Configurations
16, 32, 64
Demo
Ethernet
Apple's iPad
iPad Porn
WiFi or 3G
Will it work overseas? Costs?
Issues
Closed Environment
App Approval - No Porn
Next Version?
Demo
USB WiFi with
Antenna
Rosewill RNX-G1W
802.11b/g USB 2.0 Wireless Dongle
External 2dBi SMA Antenna
Up to 54Mbps
64/128-Bit
WEP
WPA
WPA2
Testing It
Using laptop internal antenna
Use Netstumbler to test signal
Connect USB WiFi, load drivers
Use Netstumbler to test signal
Is there a difference?
What about larger antenna?
News
PsyOps against Iraq
Video: CBS Infowarfare
Leap Frogging Technology
Video: BBC Tech Leapfrog1
Google Street Views
Video: CBS (2007.06.12) Google
Street View
Only four of the eight largest ISPs responded to
the 10-question survey, despite being contacted
repeatedly over the course of two months. AOL,
AT&T, Cox and Qwest all responded to the survey,
but only Cox answered the question, "How long do
you retain records of the IP addresses assigned to
customers."
Cox's answer: six months. AOL says "limited
period of time," while AT&T says it varies across
its internet-access offerings but that the time limits
are all "within industry standards."
Chinese police arrest three in high-tech
exam cheating scheme - Jun 9th 2007
Reuters reports, that appears to be
what has gone down during China's
recent national college entrance exam,
where three men were arrested for
relaying answers to a student from a
van parked outside the school.
Apparently, the student (who paid $1,500 for the
"service") wore a wireless microphone to read out the
questions, with the men in the van using a pair of
computers to look up the answers. That's not all the police
had to deal with, however, with them also reportedly
turning up 42 pairs of so-called "cheating shoes" with
"transmitting and reception ability" prior to the exam, as
well as some "cheating wallets" and hats.
Certification
Preparation
One of the most important policies to know is your
internet service provider's -- the company that
ferries all your traffic to and from the internet, from
search queries to BitTorrent uploads, flirty IMs to
porn.
Wired News, with help from some readers,
attempted to get real answers from the largest
United States-based ISPs about what information
they gather on their customers' use of the internet,
and how long they retain records like IP
addresses, e-mail and real-time browsing activity.
If you are Serious...
You need a network to play with
Simulator are fine, but not real
A couple of system
Desktops, Laptops...
Load different operating systems
A Home Network
Comcast, EarthLink, Verizon and Time Warner
didn't respond.
Play with it - built it, break it...
Do not use production systems.
Stuff You Need
3 machines
Cables
Network cards - different types
Hub
Switch
Router (a real one - not linksys)
Various server software
Which ISPs Are Spying on You?
Wired News 05.30.07
What Does "Topology" Mean?
Network+
Domain 1.0
Media and Topologies
How do the computers connect to each
other?
Bus
Star
Ring
Hybrid
Mesh
Topologies
Hybrid
Mesh
Centralized Hub
Bus Trunk
Star-Bus
Server
Server
Client
Bus Topology
What Is Ethernet?
Client
IEEE and the 802 Standards
Multiple Machines
Networking Protocol
IEEE 802.3 replaced DIX Standard
Single Wire - The Bus
Developed at Xerox in 1973
Industry Wide Standards
Coax Cable
Committees define the standards
3 Megabits = now 10+ Megabits
DIX - Digital - Intel - Xerox
IEEE 802 Specifications
Project 802
IEEE 802 Categories
802.1 Higher Layer LAN
IEEE 802 Categories
802.6 Metropolitan Area Network
Year = 1980
802.2 Logical Link Control (LLC)
802.7 Broadband
Month = February
802.3 CSMA/CD
802.8 Fiber Optic
In concert with ISO
802.4 Token Bus LAN
802.9 Isochronous LAN
(Integrated Voice/Data)
Standardized 1982-1983
802.5 Token Ring LAN
IEEE 802 Categories
Ethernet or IEEE 802.3?
802.10 Security
802.3 is now standard
802.11 Wireless Networks
But the name remains the same...
802.12 Demand Priority Access LAN,
100BaseVG-AnyLAN
Ethernet technically refers to the Xerox
Standard
The Big Difference
802.14 Cable Modems
How Ethernet Works
How does it send the data?
How to identify a computer?
Who gets access next?
Mac Addresses
Organizing the Data: Packets
Large files broken down
Send 1 packet at a time
Allows for retransmission
Packets Contain
Source Address
Destination Address
Data
Cyclic Redundance Check
Finding a MAC Address
Each device is a node
windows 9x:
Each has 48 bit MAC address
Allows for 281 Trillion addresses
Windows 2000, XP: ipconfig
Unique Identification
Built into the hardware
winipcfg
Let's find the mac address of our
systems
Ethernet Packet
Preamble
Destination
Source
Type
Data
CRC
winipcfg
8 bytes
6
6
2
46-1500
4
ipconfig
Using MAC Addresses
Mac Addresses
A packet goes out with a destination
MAC address
Each node listens, tries to match
If no match on MAC, ignore
If a match, read it
Some can be in promiscuous mode
More details: ipconfig /all
CSMA/CD or Who Gets to Send the
Next Packet?
Everyone talks at the same time
Data sent when available to send
More collisions
More retransmission
CSMA/CD
Carrier-Sense Multiple Access with
Collision Detection
Used by Ethernet
Terminators
Terminating resistors
Prevents signal bounce /
echo
Computer listens to network
Sends if medium is clear of data
Network useless jumble of signals
Also: Keeps all the bits
from falling out the end of
the cable!
If collision, wait and retry
Terminators
Cable Breaks
If there is a break in the cable...
Nobody can talk!
Can shutdown a network!
Ethernet Cabling Systems
No single cable solution
Network will be a collection of
10 Base 5
10 Base 2
10 Base T
and many, many more...
Coaxial Cable
Once the most popular
Types of Coaxial
Thin
(Thinnet)
Thick (Thicknet)
Coaxial Cable
Solid Core
Surrounded by insulation
Copper Wire Mesh
Surrounded by outer jacket
More resistance to interference and
attenuation
10Base5 (Thicknet)
About .5 inch thick
Rigid, difficult to work with
Cable TV: RG59
Digital Cable: RG6
10 base what?
10 base 5
10 - Megabits per second
Maximum Length
500 Meters
1640 Feet
Thicknet
Uses a Transceiver
Vampire Tap
Attachment Unit Interface (AUI)
DB-15 connector on NIC
Base - Baseband vs. Broadband
Baseband - 1 signal
Broadband - many signals
RG-8/11, 50 ohm resistence
5 - 500 meters maximum length
100 Nodes per segment
10 base 2 (Thinnet)
About .25 inch thick
Flexible, easy to work with
Maximum Length
185 Meters
607 Feet
BNC Connectors
British Naval Connectors
Repeaters
Cable Connector
How can we increase the length of a
network?
Barrel Connector
Repeats regenerate the signal
T Connector
Joins two segments
Terminator
Forms a larger network
RG-58, 50 ohm resistence
30 Nodes per segment
Repeaters
What Is a Star Bus Topology?
Network+
Domain 1.0
Ethernet Network
Physical Star
Logical Bus
Extends network (Max 370 meters)
Adds machines (Max 60)
Isolates Segment Failures
Enlarges Collision Domain
Twisted Pair Cables
Twisted Pair Ethernet
Twisted Pair
High level of fault tolerance
Unshielded Twisted Pair
UTP - Unshielded
10 Base T
STP - Shielded
Length: 100 Meters, 328 feet
Commonly used for phones
Categories of UTP
Category Mbps
1
1
2
4
3
10
4
16
5
100
5e
1000
6
1000
7
10000
Use
Telephones
Token Ring
Ethernet
Token Ring
Ethernet
Gigabit Ethernet
Gigabit Ethernet
10 Gb Ethernet
Shielded Twisted Pair
Additional shielding to eliminate
interference
Twisted Pair Connectors
RJ-45 Eight Cables
RJ-11 Telephone, 4 cables
Patch Panels
Wall Plates
RJ-45 Connectors
Twisted Pair Wiring
Connector Pinouts
Twisted Pair Wiring
Standard Straight Thru Cable
Twisted Pair Wiring
Computer Crossover Cable
A question of Color
Wiring Nightmares
Inside...
Connect 2 devices without a hub
And Out...
Pick a scheme, stick with it
T568A most common
10BaseT Limits and Specifications
Ethernet 10BaseT
10Mbps, Baseband, over TP cable
10BaseT LAN server 1,024 nodes
802.3 IEEE specification
RJ-45 connectors
UTP, STP, category 3,4,5
Hub Backbone: coaxial or fiber
Max. cable segment = 100m
Repeater can be used to extended
Connecting the Segments
How Big Can an Ethernet Network Be?
The 5-4-3 Rule
Connect multiple hubs
The 5-4-3 Rule
Max. total network length: 925m
5 cable Segments
10 Base 5 / 10 Base 2
4 Repeaters
10 Base T
Crossover Cable
Uplink Port
Beating the 5-4-3 Rule
Real Trick - message from A to B must
not pass more than 5-4-3
3 Populated Segments
Fiber Optics
Immune to EMI
Use
Twisted Pair
Star Networks
Coax
Bus / Backbones
Fiber
Rings / Backbones / Long Haul
The Connectors
Fiber Optic Modes
Fiber Optic
SC
ST
Cable Grades and Fire Code
Two Types
Polyvinyl Chloride
Flexible, easy to work with
Generates poison gas in fire
lower attenuation
immunity to interference
difficulty to tap
Plenum
Expensive, less flexible
Fire resistant
Use in walls / ceiling
Plenum
Cables
Traffic Management
Bridges and Routers
Bridges
All features that repeaters have
A networks grow, more traffic
Node's address stored in bridge
More traffic, less speed
Acts as a simple router
If it knows the address
Sends to proper segment
If Not - Send to all segments
More Collisions
Regenerates the packet
Bridges
Bridge Tables
Routers
Determine the best path for sending
data
Filtering broadcast traffic to the local
segment
Connecting network segments
Only pass data if address is known
Routers
Routing
High Speed Ethernet
Several different standards
100 Mbps
100BaseT
100BaseFX
1000 Base T
100BaseT (fast Ethernet)
UTP category 5
Ethernet 100BaseFX
Switched Ethernet
100 Mbps, Baseband, fiber-optic
Also a "Smart Hub"
412 meters half-duplex
A Hub with a Bridge
2000 meters full duplex
Redirects traffic based on MAC
Immune from electrical noise
Fewer Collisions
CSMA/CD access method
100BaseT4 (4-pair, category 5)
100BaseTX (2-pair category 5 UTP or
STP)
100BaseFX (2-strand fiber-optic cable)
More secure
Full-duplex Ethernet
All stations can talk and listen at the
same time
Gigabit Ethernet
1000 Base T
Defined in 1998
End of Lesson
Two way communications
Backbone technology
Reduces collisions
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