1 tcom 555 network management and design george mason university school of information technology...

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TCOM 555 Network Management and Design

George Mason UniversitySCHOOL OF INFORMATION

TECHNOLOGY & ENGINEERING

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First Meeting Agenda

1. INTRODUCTION 2. E-MAIL ADDRESSES (james.a.mazzei@aero.org)3. SYLLABUS REVIEW

A. GRADING STANDARDSB. GROUP PROJECT

(1) System analysis & protocol specification(2) Proposed system design and management plan (3) Presentations

D. SUPPLEMENTAL READING4. QUIZES & HOMEWORK 5. FOCUS OF COURSE6. THE BOOK’S RELATIONSHIP TO THE COURSE7. BACKGROUND & CHAPTER 1

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Telecom-Data-Network Management

Homework: 1. Send me an e-mail to james.a.mazzei@aero.org2. Revise the flowchart on page 42 of the text to conform to your idea of how it would be more efficient or effective.

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Background-Concepts & Chapter 1

1. BASIC BASICS 2. X.25 3. FRAME RELAY 4. ATM 5. GIGABIT ETHERNET 6. COMPARISONS 7. dBs & S/N 8. NYQUIST 9. SHANNON10. NETWORK OPERATION & MANAGEMENT

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Protocol

• A set of Rules Used to Enable Data Communications

• Procedures for Adding Order to the Exchange of Data

• Rules Relating to the Timing and Format of Data Transmissions

• Standard Procedures that Devices Must Accept and Use

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Standards

• Agreed Principles– De Jure– EIA (RS232)– ANSI (X.25)– ITU-T (CCITT) - (X & V Series

“Recommendations”)

• De Facto– IBM, Bell System, et.al.

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Do It Yourself

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WHO

• Naming - Addresses– Format

– Aliases

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Addressing

Curly Larry

Mo Jim

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HOW

• Connections– Type– Linkage– Bandwidth

• More Names

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Connectivity

Curly Larry

Mo Jim

A

B C

D

E

F

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WHEN

• Timing & Synchronization

• Channel Availability

• Device Availability

• Batch vs. Real Time

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Connectivity

X

Curly Larry

Mo Jim

A

B C

D

E

F

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WHEN2

• Routing

• Quality Assurance– Data Integrity– Error Handling

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Routing

Curly Larry

Mo Jim

A

B C

D

E

F

12

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WHAT

• Payload– Character– Block– Packet/Frame– Assemble/Disassembly

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Background Chapter 1

1. Data & Telecom Networks2. X.25 3. FRAME RELAY4. ATM5. GIGABIT ETHERNET

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Packets

TO FROM data…...# of #

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Layers In The OSI Stack

ApplicationPresentationSessionTransportNetworkData LinkPhysical

Network Managementuses some of theselevels to manage others

But how do they relateto each other?

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Services

Service ExampleReliable message stream Sequence of pages

Reliable byte stream Remote login

Unreliable connection Digitized voice

Unreliable datagram Electronic junk mail

Acknowledged datagram Registered mail

Request-reply Database query

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Services & Interfaces

ICI SDU

IDU

SAP

ICI SDU

Layer N+1

Interface

Layer N

SDU

Header

N-PDU

Interface Data UnitInterface Control InfoService Data UnitService Access PointProtocol Data Unit

Note: It is very important to appreciate this.

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Service Primitives

Primitive MeaningRequest An entity wants the service to do some work

Indication An entity is to be informed about an event

Response An entity wants to respond to an event

Confirm The response to an earlier request has come back

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Accasionally On Line

PC N+1PC N

Svr N+1Svr N

1 2 3 4 5 6 7 8 min

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Layers In The OSI Stack

ApplicationPresentationSessionTransportNetworkData LinkPhysical

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The Market Dropped!Sell!

7654321

7654321

7654321

7654321

7654321

7654321

APrSTNDLPh

Process 1Computer 1

P(1)OS-SQ P(2,3,4,5)

Add $, CompressP(1)OS-SQ P(n)

C(1)P(1)OS-SQ C(n)P(n)

C(1)P(1)OS C(n)P(n)

C(1)P(1)SQ C(n)P(n)

HHC(1)P(1)OS C(n)P(n)

HHC(1)P(1)SQ C(n)P(n)

GW

321

Router

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Bridge

P2 on C2P3 on C3 P4 on C4

P5 on C5

1

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Standards & ProtocolsConcepts Review

1. Interface:

2. Entities:

3. Peer Entities: 4. Primitives:

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X.25

• Packet Based

• Mesh/Partial Mesh/Star Topologies

• Layers 1 & 2 of the Protocol Stack

• First successful WAN protocol

• Connection oriented communications

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X.25

DTE DCE DCE DTE

Call RequestIncoming Call

Call AcceptedCall Connected

Full Duplex Data

Clear RequestClear Indication

Clear ConfirmClear Confirmed

CallSetup

CallClear

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Frame Relay

• Packet Based

• Mesh/Partial Mesh/Star Topologies

• Layer 11/2 Protocol of the Stack

• X.25 on Steroids

• Lobotomized X.25

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X.25 vs. Frame Relay

• X.25– 9.6Kbps - T1– High Overhead– Each Hop

• Frame Relay– 56Kbps - T3– Low Overhead– CRC at End

Nodes Only– Limited QoS

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Frame Relay Characteristics

• WAN Application

• CIR/CDR

• VCs & PVCs

• Variable Packet Length

• Multicast Capabilities

• Service Provider Based

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X.25 & Frame Relay Structures

Flag Address Data FCS Flag

Flag Address Data FCS Flag

Control X.25

FrameRelay

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Frame Relay Structure

Flag Address Data FCS Flag

DLCI

6

CR

1*

EA

1

DLCI

4

FECN

1

BECN

1

DE

1

EA

1

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Frame Relay Address

DLCI

6

CR

1

EA

1

DLCI

4

FECN

1

BECN

1

DE

1

EA

1

DLCI - Data Link Connection Identifier: Identifies logical connection (within multiplexed channel) with which the frame is associated

CR - Command Response: Not used in DL-CORE protocols EA - Address Field Extension Bit: 0 indicates another octet comingFECN - Forward Explicit Congestion Notification: Notifies to initiate congestion

avoidance (e.g., We got a lot of stuff coming.)BECN - Backward Explicit Congestion Notification: Notifies to initiate congestion

avoidance in the opposite direction of frame (e.g., We see congestion on ourreceive side.)

DE - Discard Eligibility Indicator

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Frame Relay Structure

Flag Address Data FCS Flag

DLCI

6

CR

1

EA

1

DLCI

4

FECN

1

BECN

1

DE

1

EA

1

01111110

Frame Check Sequence (16 bit CRC)

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ATM

• Fixed Frame Based

• Mesh/Switched Topologies

• Layers 1 - 3 Protocol Stacks

• SVCs & PVCs

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ATM

• WAN/MAN/LAN Application

• Multicast Capabilities

• Enterprise and/or Service Provider Based

• QoS

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Frame Relay vs. ATM

• ATM– 25Mbps - OC12+– Low Overhead– CRC at End

Nodes– High QoS– Fixed Payload

• Frame Relay– 56Kbps - T3– Low Overhead– CRC at End

Nodes Only– Limited QoS– Variable Packet

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Gigabit Ethernet

• Supports Shared & Switched Configurations

• Switching Accomplished by:

– MAC Addressing (Layer 2 Switching)

– Network Layer Addressing (Layer 3 Switching)

– ATM

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Speed Comparisons (Mbps)

Ethernet 10 100 1000

ATM 25 155/622 622

TokenRing

16 100 1000

Megabits

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Cost Comparisons

Technology 1996 2004

Shared Fast Ethernet

$137 $102

Switched Fast Ethernet

$785 $476

ATM (622) $6600 $3200

Switched Gigabit Ethernet

N/A $1505

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Decibells & Logarithms

Converting watts to dB (or milliwatts to dBm): 10 log10 1000 watts = 30 dBw

Converting dB to watts (or dBm to milliwatts):30 dBw = log-1, or log-1 (3) or 10 raised

to the 3rd power = 103 = 1000 watts

35 dBw = 103.5 = 3162.3 watts

Note: There’s a point between the 3 & 5.

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Decibells & Logarithms

dBW Watts -3 .5 0 1 3 2 6 4 9 8 10 10 20 100 30 1000 40 10000

Note: The same relationship holds with dBm and miliwatts

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Nyquist Nyquist Nyquist

Nyquist: The maximum practical data rate (samples) per channel.

Max R = 2 H log2 V

Logarithmic function to the base 2: For each # V, log V = the exponent to which 2 must be raised to produce V. Then if V = 16, the log2 of V = 4. If V = 2, the log2 of V = 1.

Then what is the maximum practical data rate for BPSK signal on a line with a bandwidth of 3000 Hz?

What is the maximum practical data rate for a QPSK signal on a line with a bandwidth of 3000 Hz?

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Shannon Shannon Shannon

Shannon: The maximum theoretical data rate per channel.

Max R = CBW x log2 (1 + S/N)

[CBW = H in Nyquist Theorem]

Then what is the maximum practical data rate for signal with a 30 dB S/N on a line with a bandwidth of 3000 Hz?

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Telecom-Data-Network Management

Telecom from where & using what?

Data from where & using what?

Networks from where & using what?

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Telecom-Data-Network Management

User AplPresent SvcsFlow ControlXmt ControlPath ControlData LinkPhysical

ApplicationPresentationSessionTransportNetworkData LinkPhysical

Apl ProtocolTransportTCP UDP

Network

SNA OSI Internet

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ApplicationPresentationSessionTransportNetworkData LinkPhysical

SNICPSNDCPSNDAP

Subnet Independent ConvergenceSubnet Dependent ConvergenceSubnet Dependent Access Protocol

Telecom-Data-Network Management

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Telecom-Data-Network Management

NetworkManagement

NetworkMaintenance

NetworkOperations

NetworkProvisioning

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Telecom-Data-Network Management

NetworkMaintenance

NetworkOperations

NetworkProvisioning

Planning Fault Management Fault ManagementDesign Configuration Mgt Trouble Ticket Admin

Performance Mgt Network Installation Security Management Network Repairs Accounting Mgt Install & Maintenance Reports Management Routine Net Tests Inventory Management Data Gathering Data Analysis

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DSN - Global Voice Network