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CBNE Prepara+on Webinar Series Webinar #1 IP Networking – The OSI Model & Layers Wayne M. Pecena, CPBE, CBNE Texas A&M University
CBNE Prepara+on Webinar Series Webinar #1
IP Networking – The OSI Model & Layers
Wayne M. Pecena, CPBE, CBNE Texas A&M University
CBNE Prepara+on Webinar Series Webinar #1
IP Networking – The OSI Model & Layers
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Overview This webinar is the first in a series that aids in the self-study for the SBE Certified Broadcast Networking Engineer™ (CBNE™) certification exam. This webinar will focus on introducing concepts of the OSI Model, TCP Model, and the application to the Physical, Network, and Transport layers as applied to IP Networking. Content will be focused on the broadcast plant where possible and is applicable to those sitting for the CBNE™ exam.
CBNE Prepara+on Webinar Series Webinar #1
IP Networking – The OSI Model & Layers
• Standards, the OSI Model, & Layers • Physical Layer Focus
– LAN Environment (interconnec9on wiring – UTP – STP – FO)
– LAN Environment (WiFi) – WAN Environment (Digital Service & Op9cal Carrier services)
• Introduc+on: – Data Link Layer – Physical Addressing (MAC) – Network Layer – Virtual Addressing (IP) – Transport Layer -‐ TCP & UDP
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What is a Network? • The founda9on for human interac9on. • A group of computers that are interconnected to share resources and informa9on.
• A group of hosts that share a common address scheme.
• Networks are oRen defined by their geographic reach: – Local Area Network -‐ LAN – Wide Area Network -‐ WAN – Metropolitan Area Network -‐ MAN – Campus Area Network -‐ CAN
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5 Things Required To Build a Network
• Send Host • Receive Host • Message or Data to Send Between Hosts • Media to Interconnect Hosts • Protocol to Define How Data is Transferred
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Protocols
Send Host Receive Host
MediaMedia
DATA
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Standards Organiza9on Overview
OSI Model Model Layers
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Standards Organiza9ons De Jure & De Facto
• IETF – Internet Engineering Task Force – The Internet Standard RFC’s Originate Here
• IEEE-‐ Ins9tute of Electrical & Electronic Engineers – Ethernet & Wireless LAN Standards
• EIA – Electronic Industries Associa9on – Focused on Physical Layer Standards
• ISO – Interna9onal Standards Organiza9on – OSI Reference Model Crea9on
• ITU – Interna9onal Telecommunica9ons Union – Global Telecommunica9ons Standards (ie PSTN)
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IETF – Internet Engineering Task Force • Request for Comments – RFC’s
– The “Standards Bible” of the Internet – Used to Explain All Aspects of IP Networking – Nomenclature “RFC xxxx”
• Requirement Levels: – Required – Recommended – Elec9ve – Limited Use – Not Recommended
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www.rfc-editor.org/rfc.html
IEEE-‐ Ins9tute of Electrical & Electronic Engineers
• Project 802 Ethernet Standards:
– 802.1 Bridging – 802.3 Ethernet – 802.11 Wireless
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http://standards.ieee.org/about/get/
ITU – Interna9onal Telecommunica9ons Union
• ITU-‐T Sector: – ITU-‐T G-‐Series TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND
NETWORKS – ITU-‐T H-‐Series AUDIOVISUAL AND MULTIMEDIA SYSTEMS – ITU-‐T I-‐Series INTEGRATED SERVICES DIGITAL NETWORK – ITU-‐T X-‐Series DATA NETWORKS, OPEN SYSTEM
COMMUNICATIONS AND SECURITY
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http://www.itu.int/ITU-T/info/structure.html
OSI Model Open Systems Interconnec9on (OSI) Model
Developed by the Interna9onal Organiza9on for Standardiza9on (ISO)
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Networking Focus
OSI Model Expanded
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Application
Session
Presentation
Transport
Physical
Data Link
Network
Application Layers
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5
6
4
1
2
3
Bits
TCP / UDPSPX
IPIPX, ICMP, X.25
EthernetToken Ring, DECnetArcnet, PPP, WAP
Bits (data stream)
SEGMENT
PACKET(Datagram)
FRAME
Data Flow
Layers
Bits
PORT
IP Address
MAC Address
“All People Seem To Need
Data Processing”
OR “Please Do Not
Throw Sausage Pizza
Away”
“Some People Fear
Birthdays”
Protocol Data Unit PDU
Encapsula9on Data is “Encapsulated” As It Travels Through the Model
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Encapsula9on Detail
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SourcePort
DataDestination
Port
Destination IP Address
SegmentProtocolSource IP Address
Source MAC Address
CRC/FCSPacketEther-FieldsDestination
MAC Address
1110010001100000101010001110011011001110001010101011111
SEGMENT
PACKET(Datagrams)
FRAME
BITS
Encapsula9on & De-‐Encapsula9on
Application
Session
Presentation
Transport
Physical
Data Link
Network
Segment
Bits
Frame
Packet
PDUUpper Level Data
Upper Level Data
Data
Data
TCP Header
IP Header
LLC Header
0110010111001000111000111010
DataMAC Header
CS
CS
Application
Session
Presentation
Transport
Physical
Data Link
Network
Upper Level Data
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TCP/IP Model DOD Model Stack or TCP/IP Model Stack Focused on IP
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Application
Session
Presentation
Transport
Physical
Data Link
Network
Application
Host to Host
Network
Internet
OSI Model DoD Model
Application
Transport
Network Interface
Internet
TCP/IP Model
TCP/IP Focused
The Models in Comparison
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Application
Session
Presentation
Transport
Physical
Data Link
Network
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5
6
4
1
2
3
Transport
Internetwork
Network AccessProvides Media
Interface, Topology
Provides Data Sequencing, Flow Control, Integrity
Provides Logical Addressing, Fragmentation,
End-End Delivery
Provides Physical Addressing, Error
Correction
Service Provided to Applications
Provides Conversation Control
Provides Data Formatting
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1
2
LLC
MAC
The OSI Model TCP/IP Model Encapsulation
Application4
The OSI Model is a conceptual framework model independent of protocol.
The TCP/IP Model is an implementation of the OSI Model that describes the framework of the TCP/IP protocol suite.
TCP/IP describes how data is addressed, routed, and formatted for end-end connectivity between computer hosts.
IP
Network Interface
TCP UDP
Application Data
Segments
Bits
Frames
Packets
1 -‐ The Physical Layer
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Receives frames from the Data Link layer Places bits onto the physical network medium Controls the signaling Takes bits off the physical network medium Sends constructed frames to the Data Link Layer
Ethernet Media Evolu9on
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Thicknet Vampire Tap
Thinnet
Topology Also Migrates from “Bus” to “Star” Based
IEEE Cable Designation Topology Speed / Duplex / Media 802.3 10-Base-5 Bus 10Mbps / Half / Thicknet 802.3 10-Base-2 Bus 10Mbps / Half / Thinnet 802.3 10/100-Base-T Star 10/100 Mbps / Half-Full / UTP 802.3u 100-Base-T Star 100 Mbps / Half-Full / UTP (Cat 5) 802.3u 100-Base-FX Star 100 Mbps / Full / MM Fiber 802.3ab 1000-Base-T Star 1000 Mbps / Full / UTP (Cat 6) 802.3z 1000-Base-SX Star 1000 Mbps / Full / MM Fiber 802.3z 1000-Base-LX Star 1000 Mbps / Full / SM Fiber 1310nm 802.3z 1000-Base-ZX Star 1000 Mbps / Full / SM Fiber 1550nm and 20 Gigabit, 40 Gigabit, & 100 Gigabit Ethernet are emerging ……
Ethernet Physical Medium
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The OSI Model & Ethernet Types
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DataLink
Layer
PhysicalLayer
PhysicalLayer
802.2LLC
MACE
ther
net
Eth
erne
t80
2.3
Eth
erne
t80
2.3a
bG
igab
it E
ther
net
(cop
per)
Eth
erne
t80
2.3z
Gig
abit
Eth
erne
t
Eth
erne
t80
2.3u
Fas
t Eth
erne
t
Tok
en R
ing
802.
6
FD
DI
Ethernet GBIC & SFP Modules
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“Giga-Bit Interface Converter” - GBIC Transceiver SC Fiber Connector “Single Form-factor Pluggable” – SFP (mini GBIC) Transceiver LC Fiber Connector Copper or Optical Based Transceiver to Provide Flexible Physical Interface
- 1000Base-T (some support 100/100-Base-T as well) - 1000Base-SX / LX / ZX - Multi-Mode / Single-Mode Fiber
Ethernet Auto-‐Nego9a9on • Auto Configura9on of Port Duplex & Speed
– U9lizes Ethernet FLP & NLP Bursts • Duplex – Half Duplex or Full Duplex • Speed -‐ 100 / 1000 Mbps • Be Careful With Depending Upon Auto-‐Nego9a9on
– 10 Mbps Full Duplex is Not a Valid Mode – 100 Mbps Half Duplex Indicates Auto-‐Nego9a9on Failure – Duplex Mismatch = Poor Performance = CRC Errors
• Best Prac9ce – Sta9c Configure Infrastructure
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Duplex Mismatch Result
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Switch
Host
RX
TX
Half – DuplexSwitchPort
TX
RX
Full – DuplexServer Interface
Always TransmitMonitored for ReceivedFrames
Transmits WhenNo Receive Activity
When Duplex Mismatch Occurs: High Collision Rate Results, thus Performance Reduced
WAN Technology • Generally Categorized as Dedicated, Circuit Switched , or Packet Switched: • Dedicated
– T-‐Carrier (data) – Op9cal Carrier
• Circuit Switched – ISDN – BRI – ISDN – PRI – T-‐Carrier (voice)
• Packet Switched – X.25 – Frame Relay – ATM – ADSL / HDSL – Metro Ethernet Offerings
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Wireless Fidelity Networking • 802.11 Standards
– 802.11 2.4 gHz 2 Mbps
– 802.11b 2.4 Ghz 11 Mbps
– 802.11a 5 Ghz 54 Mbps
– 802.11g 2.4 Ghz 54 Mbps
– 802.11n 2.4/5 Ghz 600 Mbps
• Frequency Bands (ISM & UNII): – 2.4 Ghz 2.4-2.497 Ghz ISM
– 5 Ghz 5.15 – 5.875 Ghz UNII
• Wireless Security – WEP
– WPA
– WPA2 (802.11i)
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2.4 Ghz WiFi Channels
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WiFi Security Summary
WPA WPA2 802.11i
Use SOHO Enterprise Enterprise
Authen+ca+on PSK 802.1x / PSK 802.1x
Encryp+on 128-‐bit / TKIP 128-‐bit AES 128-‐bit AES
Ad Hoc Support No Ad Hoc No Ad Hoc Allows Ad Hoc
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PSK = Pre-Shared Key TKIP = Temporal Key Integrity Protocol AES = Advanced Encryption Standard
WiFi Propaga9on Factors
• Free Path Loss Model Applies
• Energy Loss Factors: – Absorp9on – Reflec9on – Mul9path – Scamering – Refrac9on
• Remember the “Link Budget”
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Receive Power (dBm) = Transmit Power (dBm) + Gain (dB) – Loss (dB)
2 -‐ The Data Link Layer
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Data LinkLayer
LLC Sublayer
MAC Sublayer
Network Layer Packets Encapsulated into Frames
Hardware Addressing Scheme Implementation
Unique Sub-Layers: LLC & MAC
Unique
The Data Link Sub-‐Layers:
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LLC Sublayer
MAC Sublayer - Physical Addressing (MAC Address) - Transmitting On The Media
- Flow Control - Error Control (CRC) - Synchronization
Data Link Functions:
Package Frames
Transmit Frames
Control Flow
Error Correction
Network ID
Data Link Frames: Are Likely Ethernet Layer 2 Protocol Data Units
But, they could be: Token Ring Layer 2 Protocol Data Units
Frame Relay Layer 2 Protocol Data Units
Ethernet Basics IEEE 802.3
• The “de facto Standard” of Networking Today! • Based Upon Conten9on-‐Access to the Wire • 4 Basic Building Blocks of the Ethernet System – The Ethernet Frame
• 802.3 Raw Early Novell Netware IPX • 802.2 LLC Current Novell NetWare IPX • Ethernet II (DIX) TCP/IP • Ethernet SNAP IPX, AppleTalk v2
– Media Access Control Protocol – Signaling Components – Physical Medium
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Ethernet Frame – Layer 2
Preamble TypeSource
AddressDestination
Address Data CRC
An Ethernet II (DIX) Frame
8BYTES
6BYTES
6BYTES
2BYTES
46 – 1500 BYTESVARIABLE
4BYTES
Invalid FRAME Lengths:< 64 BYTES = “RUNT” FRAME
> 1518 BYTES = “GIANT” FRAME
Note – Preamble Not Used in Frame Length Calculation
TypeSource
AddressDestination
Address Data CRC
64 Byte Minimum
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MAC Address “Media Access Control” Address
• Known as Hardware Address or Physical Address • 48 bit / 6 Byte Unique Address in Hardware • Expressed as 6 Groups of 2 Hex Characters
00:A0:C9:14:C8:29 • 1st 3 Bytes = Organiza9onal Unit Iden9fier “OUI”
00:A0:C9 OUI Assigned to Intel • 2nd 3 Bytes = Network Interface Controller “NIC”
14:C8:29 is Unique to Hardware • Also Expressed as: 00-‐A0-‐C9-‐14-‐C8-‐29
00A0.C914.C829
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MAC Lookup: http://hwaddress.com/
Byte6
Byte1
Byte2
Byte3
Byte4
Byte5
6 Bytes
Organization UniqueIdentifier “OUI”
Network InterfaceController “NIC”
3 -‐ The Network Layer
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Network 1 Network 2
Network 3 Network 4
Network 5
Router A
Router B
Router C
Internetwork Communications Focused: Packet Delivery from Source Host To Destination Host Logical Addressing Scheme Implementation Routing Decisions via Routing Protocols
IP Packet – Layer 3 RFC 791
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Version(4)
Header(4)
Precedence / Type(8)
Length(16)
Identification(16)
Flag(3)
Offset(13)
Time to Live(8)
Protocol(8)
Header Checksum(16)
Source IP Address(32)
Options & Padding(0 or 32)
Destination IP Address(32)
Packet Payload(Transport Layer Data)
32 bits
20Bytes
Physical & Virtual Addressing • MAC Address
– Layer 2 Physical Address (local network segment)
• IP Address – Layer 3 Logical Address (global routed)
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172.15.1.1 172.15.2.2 DATA Trailer00:12:3F:8D:4D:A7FF:FF:FF:FF:FF:FF
DestinationMAC
SourceMAC
DestinationIP
SourceIP
IP Packet
Ethernet Frame
Simplified Representation
4 -‐ The Transport Layer
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Implements Reliable End-End Data Transport
Implements Error Detection / Correction
Establishes Virtual Connect Between Hosts
Provides Segmentation, Sequencing, Flow Control
Send HostReceive Host
TCP Basics RFC 793
• Referred to as a “Connec+on – Oriented” Protocol • Guaranteed Or Reliable Data Delivery
– Acknowledgment of Packet Receipt – Retransmission Occurs if Packet Not Received or Error Occurs
• High Overhead thus Slow • A TCP Conversa9on Requires Establishment of a 2-‐Way “Session” Between
Hosts
• TCP Windowing – Segment Acknowledgement – Dynamic Window Sizing – “Slow-‐Start”
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TCP Session
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Segment Acknowledgment
TCP Connection Established
TCP 3-‐Way Handshake
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Send HostReceive Host
I Want to Connect. My Sequence Number is 100
SEQ = 100 CONTROL = SYN
I Received Your Sequence 100! My
Sequence Number is 1 & Ready for 101
SEQ = 1ACK=100
CONTROL = SYN, ACK
I Received Your Sequence 1 & Ready for
Sequence 2
SEQ = 101ACK=2CONTROL = ACK
UDP Basics RFC 768
• A “Simple” Protocol or “Lightweight” • Low Overhead = Fast • “Best Effort” – Non-‐Guaranteed Data Delivery • Why Use?
– Required for Real-‐Time Applica+ons -‐ VoIP or Video Transmission” – Latency More Detrimental Than Data Loss
• Used By: – DNS – SNMP – DHCP – TFTP – And others …..
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UDP Session
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TCP vs UDP
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TCP – UDP Characteris9cs Compared
TCP -‐ RFC 793 • Referred to as a “Connec+on –
Oriented” Protocol • Guaranteed Or Reliable Data
Delivery – Acknowledgment of Packet Receipt – Retransmission Occurs if Packet Not
Received or Error Occurs
• High Overhead thus Slow • A TCP Conversa9on Requires
Establishment of a 2-‐Way “Session” Between Hosts
UDP -‐ RFC 768 • A “Simple” Protocol or
“Lightweight” • Low Overhead = Fast • “Best Effort” – Non-‐Guaranteed
Data Delivery • Why Use?
– Required for Real-‐Time Applica+ons -‐ VoIP or Video Transmission”
– Latency More Detrimental Than Data Loss
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TCP Handshake / UDP Data Flow
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Send HostReceive Host
SYNCHRONIZE – Establish Connection
SYNCHRONIZE & ACKNOWLEDGE
ACKNOWLEDGE – Send Data
TCP
Send HostReceive Host
UDP
SYNCHRONIZE – Establish Connection
SYNCHRONIZE & ACKNOWLEDGE
ACKNOWLEDGE – Send Data
Send Data
Send Data
Send Data
Addi9onal Study:
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The OSI Model: http://www.routeralley.com/ra/docs/osi.pdf Ethernet Basics: http://www.routeralley.com/ra/docs/ethernet.pdf WiFi Basics: http://www.routeralley.com/ra/docs/80211_wireless_intro.pdf http://www.radio-electronics.com/info/wireless/wi-fi/ieee-802-11-standards-tutorial.php TCP vs UDP: http://www.routeralley.com/ra/docs/tcp_udp.pdf
Reference Slides:
• UTP Cable Types • Ethernet Cable Wiring • Ethernet Cable Types • Ethernet CSMA/CD Flowchart • Fiber Op9c Connector Types • Fiber Op9c Cable Handling • WAN Components • WAN Link Types • T1 Configura9on • ISDN Basics • ISDN Reference Configura9ons
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UTP Cable Types
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Category Maximum Speed Applica+on
1 1 Mbps Voice (not for ethernet)
3 10 Mbps Ethernet 10BaseT
5 100 Mbps Ethernet 100BaseT
5e 1 Gbps Ethernet 1000BaseT
6 10 Gbps Ethernet 10GbE
6a 10 Gbps Ethernet 10GbE
For More Information: http://www.lanshack.com/cat5e-tutorial.aspx/
Ethernet Cable Wiring -‐ Straight
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Ethernet Cable Wiring -‐ Cross
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Ethernet Cable Types
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Cable Type Legend
Straight-Through
Cross-Over
Router 1 Router 3Router 2
Ethernet 0
Ethernet 0 Ethernet 0
Ethernet 1
Ethernet 1
Ethernet 3
Ethernet 1
EIA/TIA-568A EIA/TIA-568B
EIA/TIA-568B EIA/TIA-568B
MDI
MDIXMDIXMDIX
MDI
MDI
MDI
Ethernet Media Access Control Protocol Carrier Sense Mul9ple Access with Collision Detec9on – “CSMA/CD”
• CSMA/CD Process:
– Listen Before Sending – Detect Collisions – Jam Signal & Random Backoff
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Fiber Op9c Connector Types
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Fiber Op9c Cable Handling
• Bend Radius • Cleaning
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Fiber Optic Cable Handling: http://www.thefoa.org/tech/guides/INSTL.pdf
WAN Link Types
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Line Type: Signaling Type: Bit Rate
64 DS0 64 kbps
T1 or DS1 DS1 1.544 Mbps
T3 or DS3 DS3 44.735 Mbps
SONET OC:
SONET STS:
Bit Rate
OC-‐1 STS-‐1 52 Mbps
OC-‐3 STS-‐3 155 Mbps
OC-‐12 STS-‐12 622 Mbps
OC-‐48 STS-‐48 2400 Mbps
OC-‐96 STS-‐96 5000 Mbps
WAN Component Example Point – Point T-‐1 or DS-‐1
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Router 1 Router 2
Ethernet 1
CSU/DSU CSU/DSUDS-1WAN
Ethernet 1
Serial 1Serial 1
Possible Interfaces That Might Be Found
T1 Configura9on • T1 Types:
– Channelized (voice) – PRI (ISDN) (voice or data) – Clear Channel (data)
• Encoding – AMI (voice) – B8ZS (data)
• Framing – D4 Super Frame (voice) – Extended Super Frame (data)
• Timing – Must specify source
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Additional Study: http://www.oocities.org/~katmci/pdfs/t1.pdf
ISDN Basics • Integrated Services Data Network
– Bearer Channel “B” – Payload Channel – Delta Channel “D” – Signaling Channel
• Configura+ons: – Basic Rate Interface – BRI “2B + D” – Primary Rate Interface – PRI “23B + D”
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Additional Study: http://docwiki.cisco.com/wiki/Integrated_Services_Digital_Network
ISDN Reference Configura9ons:
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TA = Terminal Adapter TE1 = Terminal Equipment type 1 TE2 = Terminal Equipment type 2 NT1 = Network Termination type 1 NT2 = Network Termination type 2 LT = Line Termination 8 devices supported, but only 2 at a time
CBNE Recommended Study:
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My Favorite:
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What is Ahead? • CBNE Webinar #2 – IP Networking – Part 2
• Unicast vs Mul9cast • Rou9ng • Switching • VLAN & VPN • QOS for Audio & Video • CBNE Webinar #3 – IP Networking – Part 3 • IP Address Assignment & Management • IPv6 • Wireless Network Performance • CBNE Webinar #4 -‐ IT Infrastructure Basics • High-‐Availability Design and Architecture • Hard Drive Types and Applica9ons • System Fault Tolerance, RAID, SAN, NAS • UPS Systems • CBNE Webinar #5 -‐ IT Based Audio-‐Video Systems • Networked Media • Storage and Play-‐out Systems as Op9mized for Audio &
Video • Large Scale Backup Strategies • Database Connec9vity (ODBC) • SDI
• CBNE Webinar #6 -‐ Digital Content Management – Part 1
• Basics of File-‐Based Workflows • SMPTE/EBU Metadata framework • General Metadata wrappers • CBNE Webinar #7 -‐ Digital Content Management – Part
2 • Process of MAM (Media asset management) • Content Management • Digital Rights management • CBNE Webinar #8 – Final Review • CBNE Content Scope Review • Study & Reference Materials • Prac9ce Prac9cal Exam Topics
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Thank You for A4ending! Wayne M. Pecena Texas A&M University Office of Informa9on Technology w-‐[email protected] [email protected] 979.845.5662
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? Questions ?
