ch3 network implementation

7/31/2019 Ch3 Network Implementation

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Network Implementation

and Management

Strategies


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Outline

Explain why a network implementation strategy isneeded

Examine the principles of network design

Explain why a network management strategy is needed

Describe network management categories and relatedactivities

Classify current network management tools according to

functionality Examine different network management strategies

Select a management strategy for this book


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Network Implementation Strategy

Design


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Network Implementation Design

AnalysisCategory Issues

Geographical Distribution 1. Office Subnets LAN2. Department (many offices) Subnets LAN3. Division ( many departments) LAN WAN4. Organization ( many divisions)

Localq LANq MANq WAN

Nationalq WAN

Globalq WAN


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Analysis (cont.)

Subnets 1. How many Connectivity

q Bridges

q Switchesq Routers

2. Ethernet Wireless

q Number of receivers 10BASET

q Location of hub(s) 10BASE2

10BASE5

How many IP addressesq Static addressesq Addresses supplied by DHCP


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Analysis (cont.)LAN 1. How many

2. Domain names3. DNS (Domain Name Service) configuration4. Network address5. Subnets

How many

5. ConnectivitySwitched Ethernet

Router

6. Ethernet7. Token Ring8. FDDI (Fiber Distributed Data Network)


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Analysis (cont.)MAN (Metropolitan Area

Network)

1. Connectivity between LANsq FDDIq SONET(Synchronous Optical Network)q LANq

ATMq SMDS ( Switched Multi-megabit DataService)q DQDB (Dual Queue Dual Bus)q Ethernet

WAN 1. Connectivity between LANs or MANsq PSTNq X.25q TI-T3q SONETq Frame Relayq SMDSq ATMq Distribution of services


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Analysis (cont.)Bandwidth Requirements 1. Video Bandwidth

Constant

Time Dependent

Bandwidth on Demand

2. Audio Bandwidth

Constant Time Dependent

Bandwidth on Demand

3. Teleconferencing Bandwidth

Media Requirements 1. Cable2. Wireless3. Microwave4. Satellite5. Optical Fiber


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Analysis (cont.)Technology 1. What is available now

2. Minimum required for the job3. Technology improvements during next 5 years4. Required to support expected growth

Service Level Agreements

(SLA)

1. Specified bandwidth available at any time2. Specified bandwidth available during specifiedtime periods3. Bandwidth on demand

Security Requirements 1. Location of firewalls

2. Firewall capabilities3. Location of proxy servers4. Encryption and authentication needs5. Network Intrusion Detectors (NID)

Budget 1. To support resources of optimum network2. To support resources of minimum network


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A Network Management Categories

and Associated MetricsCATEGORY METRICS

Reliability Transmission error rates Dropped packets Link failures

Faults Proactive prevention Detection Location Correction time

Availability Mean time between failures (MTBF) of network

Performance Time to provide a response to the userq Processor total useq Processor interrupts/secq Processor queue lengthq Transmit packet lengths


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and Associated Metrics (cont.)Throughput Bytes per second that a user can expect to transmit reliably.

Guaranteed throughput based on Service Level Agreement(SLA)

Data Packet throughput

Voice Ordered packet throughput

Video Link bandwidth Bandwidth on demand

Use Packets/sec Transactions/sec

Resource Use Application software Network devices Services Permanent storage CPU


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and Associated Metrics (cont.)Policies Traffic

What's Critical How many network control packets Which threshold alarms Alerts on what events What's Non-critical Backup-what and how often Application testing Software upgrades-how often Administration Type of service availability required Security level required Firewall protection requirements Network Intrusion Detection needs Number of Software License requirements User rights requirements and how distributed among whichusers.

Redundancy Number of redundant systems required Critical alternate paths

User Support Automatic responses to user questions about procedures Automatic responses to user questions about networkproblems Automatic reporting of problems and solutions to users and to

a database


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and Associated Metrics (Example-

Micromuse Netcool/OMNIbus)


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ISO Network Management

Categories


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ISO Network Management

Categories (Cont.) (Performance Management)

Tells you how the network is doing

(Fault Management) Tells you what your network is doing

(Configuration Management) Tells you where everything is in the network

(Security Management) Tells you who is using your network

(Accounting Management) Tells you when your network is used


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Performance Management (

) Performance Management

Measuring the performance of network

hardware, software, and media Measuring MetricsOverall throughput

Percentage utilization

Error rate

Response time


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Performance Management Sub-

Categories and Related ActivitiesCollecting Baseline

Utilization Data

Measuring link utilization using a probe Counting packets received/transmitted by a specificdevice Measuring device processor usage

Monitoring device queue lengths Monitoring device memory utilization Measuring total response times

Collecting a History of

Utilization Data

Measuring utilization and response times at differenttimes of the day Measuring utilization and response times on differentdays over an extended period

Capacity Planning Manually graphing or using a network management toolto graph utilization as a function of time to detect trends Preparing trend reports to document projected need forand the cost of network expansion.


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Performance Management Sub-

Categories and Related Activities (cont.)Setting Notification

Thresholds

Having a network management tool poll devices forvalues of critical parameters and graphing these values as afunction of time Setting polling intervals Setting alarms/alerts on those parameters when thethreshold is reached or a percentage of it is reached Initiating an action when the threshold is reached sucha sending a message to the network manager.

Building Databases Having the network management tool create a databaseof records containing device name, parameter, thresholdand time for off-line analysis. Using the database to extract time dependence ofutilization Using the time dependence of parameters to decide

when network upgrades will be necessary to maintainperformance

Running Network

Simulations

Using a simulation tool to develop a model of thenetwork Using the models parameters and utilization data tooptimize network performance

Latency Query/Response time interval


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Implementing Steps of

Performance Management1.

2.

3.(Threshold)

4.


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:processor load, disk access rate, network

interface card utilization/:packet forwarding rate, processor load,

percentage of dropped frames on eachinterface, number of packets being held in aqueue.


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(Link Utilization)

= bandwidth

total bits sent + total bits received

util%

bandwidth

Max (total bits sent , total bits received)=util%

(e.g, Ethernet, Token Ring, FDDI)

Full-Duplex Serial Link(e.g. 64K, ..., T1, T3)


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SNMP

SNMP MIB II ifInOctets ifOutOctets SNMP

ifInOctetsifOutOctets

= / ()


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Example

T1(1.544Mbps)

10:00 AM: ifInOctets = 1,500,000

ifOutOctets = 1,200,000

10:05 AM: ifInOctets = 2,500,000

ifOutOctets = 7, 200,000


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In: 2,500,000 - 1,500,000 = 1,000,000 Bytes

Out: 7,200,000 - 1,200,000 = 6,000,000 Bytes = Max(1,000,0006,000,000) Bytes

= 6, 000,000 Bytes

= 48,000,000 bits

Util% = 48,000,000/(1,544,000 60 5) 100%

= 10.36%


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Service Level Measurement

Total Response Time

Rejection Rate Availability


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Service Level Measurement (Cont.)

Total Response Time

the amount of time it takes a datum to enter

the network and be processed and for aresponse to leave the network.

From the viewpoint of applications

Round Trip Time (R.T.T) is measured fromthe viewpoint of transport protocol.


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Service Level Measurement (Cont.)

Rejection Rate

the percentage of time the network cannot

transfer information because of the lack ofresources and performance.

Availability

the percentage of time the network is

accessible for use and operational.Usually measured as MTBF (Mean Time

Between Failure)


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Analysis of Performance

InformationGraphic performance informantion

Historical plots: weekly, monthly,

quarterly, yearly

Real-time graphical analysis

Trend Prediction


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Example of Performance

Management


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Management (TANET-NCTU-1)


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Management (TANET-NCTU-2)

Reference: http://mrtg.twaren.net/mrtg
http://mrtg.twaren.net/mrtghttp://mrtg.twaren.net/mrtg


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What to be Analyzed/Graphed?

Device Information

memory usage, processor utilization, disk

access rate, number of sessions. Link Information

utilization, error rate, error percentage


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Threshold Setup

Set thresholds on a variety of items

affecting network performance

When the thresholds are crossed, events

are reported.

In general, the values of thresholds are

determined according to past experience.


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Thresholds

Threshold Priority

In general, priority: low, medium, high

Multiple threshold values for the same item

Thresholds for multiple items

Use rearmmechanism to avoid frequent

threshold events


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Rearm

Threshold

Rearm

time

util%

1 2 3 4 5 6 7


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Performance Prediction

Use Regression to predict future

trend.Apply Statistics Theory

Should consider possible factors that

affect the prediction.Network Simulation


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Prediction

time

util%

Predicted utilization increase

Computed actual utilization

Threshold value


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Fault Management ( )

Fault Management Detection of a problem, fault isolation and correction

to normal operation

A goal is to use trend analysis to predict faults andchange network conditions so that the network isalways available to users

Fault Management involves the following steps Discover the problem

Isolate the problem Fix the problem (if possible)


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Fault Management Sub-Categories

and Related ActivitiesPrioritization Prioritize faults in the order in which they should be addressed

Use in-band management packets to learn about importantfaults Identify which fault events should cause messages to be sentto the manager Identify which devices should be polled and at what intervals

Identify which device parameter values should be collectedand how often Prioritize which messages should be stored in the managersdatabase

Timeliness Required Management Station is passive and only receives eventnotifications Management Station is active and polls for device variable

values at required intervals Application periodically requests a service from a serviceprovider

Physical Connectivity

Testing

Using a cable tester to check that links are not broken


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Fault Management Sub-Categories and

Related Activities (cont.)Software ConnectivityTesting

Using an application that makes a request of another devicethat requires a response.

q The most often application for this is Ping.Exe. It callsthe Internet Control Message Protocol ( ICMP) whichsends periodic Echo Request messages to a selecteddevice on a TCP/IP networkq Application on one device makes a request of an

application on another deviceDevice Configuration Devices are configured conservatively to minimize chances of

dropped packets.

SNMP Polls Devices are periodically polled to collect network statistics

Fault Reports

Generated

Thresholds configured and alarms generated Text media used for report Audio media used for report A color graphical display used to show down devices Human manager is notified by pager

Traffic Monitored Remote Monitors used Protocol analyzers used Traps sent to Network Management Station Device statistics monitored

Trends Graphical trends generated to identify potential faults


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Executing Steps for Fault

Management Discover the problem

Identifying the occurrence of a fault on

the network.

Isolate the problem

Isolating the cause of the fault.

Fix the problem (if possible)

Correcting the fault.


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Discover the Problem

Event report

(Event Report)

Periodic Polling


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Periodic Polling

5~15

SNMP: Counter (32-bit)


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PING

PING: Packet Internet Groper

PINGICMP ECHO / ECHO Reply

TCP/IP

(Round Trip Time) (Packet Loss Rate)


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An Example of PING


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Ping

(Log)

(Log)

(Interface)

(Operational Status)


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()

(Interpret Event)

(Polling)

(Event Correlation)

(Polling)

/(Event/Action)

()

Reply Poll Event


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Network Polling Receive Network Event

Critical Network Event

Interpret Network Event

Event=

Link Down ?

Check Carrier Signal on Source

Carrier

Exist ?

Alert User LinkDown

Put Interface in Loopback

Test Physical Layer

Test

Pass ?

Alert User Physical

Layer Down

Alert User

Remote Device Down

Alert User

Generate Generate

No

No

No

Yes

Yes

Yes


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()

(Text)

(Picture)

(Audio)

PagerB.B. Call

E-mailE-mail


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POP

POP

Mail

WWW

DNS

RAS

T1

Channel/Port

Critical

MajorMinor

Warning

Normal

Unknown

Disable


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State Critical Major Minor Warning Normal Unknown

Color

>80% >60% >40% >20% Threshold

Al


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Round Trip TimeThreshold Setting

Trouble Ticketing

Audio Alarm

Pager Alarm

E-Mail Alert

AlarmReporting


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Example of Fault Management

Internet

RMONDevice

UNIX....

FDDI

UNIX PC

Firewall/ Router ....

...

....

...

PC UNIX

PC

UserDNS

MailServer

WWWServer


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Example of Fault Management


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Configuration Management (

) Configuration Management

The process of finding and setting up

(configuring) network devicesAutomated configuration is becoming a more

important part of network management as the

sizes of networks grow


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Configuration Management Sub-

Categories and Related ActivitiesConfiguration(Local)

Choice of medium access protocol Choice of correct cabling and connectors Choice of cabling layout Determining the number of physical interfaces on devices Setting device interface parameter values

q Interruptsq I/O Addressesq

DMA numbersq Network layer addresses (e.g. IP, NetWare, etc)

Configuration of multiport devices (e.g. hubs, switches androuters) Use of the Windows Registry Comparing current versus stored configurations Checking software environments SNMP service

Configuration

(Remote)

From the network management stationq Disabling device portsq Redirecting port forwardingq Disabling devicesq Comparing current versus stored configurationsq Configuring routing tablesq Configuring security parameters such as communitystrings and user namesq Configuring addresses of management stations towhich traps should be sent

Verifying integrity of changes


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Categories and Related Activities (cont.)

Configuration

(Automated)

Using the Dynamic Host Configuration Protocol (DHCP) toconfigure IP addresses Using Plug and Play enabled NICs for automatic selection of

interrupts and I/O addresses Domain Name Services (DNS) addresses Trap messages from agents


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Categories and Related Activities (cont.)Inventory

(Manual)

Maintaining records of cable runs and the types of cablesused Maintaining device configuration records Creating network database containing for each device:

q Device typesq Software environment for each deviceq operating systems

q utilitiesq driversq applicationsq versionsq configuration files (.ncf, .ini, .sys)q vendor contact informationq IP addressq Subnet address

Inventory

(Automated)

Auto-discovery of devices on the network using an NMS Auto-determination of device configurations using an NMS Creation of a network database Auto-mapping of current devices to produce a networktopological map Accessing device statistics using an NMS and the DesktopManagement Protocol


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(SNMP)

(Autodiscovery)


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Auto-discovery

A method used by a network

management system to dynamically findthe devices attached to a data network.

1.Ping2.


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1.Ping

(1). Send out a query, such as ICMP Echo

(ping) to every possible address on the

network.

(2). When a device answers the query, ask

for detailed information using networkmanagement protocol (e.g. SNMP).


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Eexample of Auto-discovery (I)

* Suppose the IP Address of NMS is 140.131.59.20 and

the network attached is a Class B network (i.e. netmask

is 255.255.0.0).

=> Possible Addresses: 140.131.0.1 ~140.131.255.254

* If there exists another network, e.g. 163.25.149.0,

interconnected with network 140.131.0.0, there exists a

router containing at least two interfaces with IP address140.131.x.x and 163.25.149.x.

* Use SNMP to query the IP address table of the devices

found by Ping, we can get more information about the

existence of other networks and devices.


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Eexample of Auto-discovery (II)

* Suppose the IP Address of NMS is 140.131.59.20

and its default gateway is 140.131.59.254.

=>

* Use SNMP to query 140.131.59.20 itself or

140.131.59.254.

ARP Cache, TCP/UDP Connection Table, IP Address

Table, Routing Table.* Use SNMP to query the devices found in the

previous query.


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Compound Status

Status Propagation

Default

Propagate Most Critical

Propagate At Threshold Values (0-100%)

% Warning

% Minor

% Major

% Critical


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Manual modification is not efficient.

Automatic modification should be recorded

NMS can verify the configuration change.


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Stored in a central location

Consistency and Availability of configuration

data is important.

CM data can be stored in ASCII Text Files

or DBMSs.


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Provide for central storage of all network

information.

Autodiscovery mechanismAutomapping facility

Automatic data acquisition

Allow user to manually add additional

configuration information

Search function


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()

Automatically compare current and stored

configuration data.

View running configuration graphically. Make configuration change.

Centralized storage and easy retrieval of

data.

Configuration Event/Alarm.

Graphical logical/physical view of devices


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Configuration Alarms


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()

The use of DBMS

Evaluate device configurations

Allow complex query of data in DBMS.

Produce inventory reports.

Provide simple query interface for critical

data.


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Example of Traceroute

E l f C fi ti


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Example of Configuration

Management


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Example of Configuration

Management: (CHTNet)


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Security Management ( )

Security Management

The process of controlling access to

information on the networked system

S S


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Security Management Sub-

Categories and Related Activities

Applying Basic

Techniques

Identifying hosts that store sensitive information Management of passwords Assigning user rights and permissions Recording failed logins Setting remote access barrier codes Employing virus scanning Limiting views of the Enterprise network Tracking time and origin of remote accesses to servers

Identifying Access

Methods Used

Electronic Mail File Transfer Web Browsing Directory Service Remote Login

Remote Procedure Call Remote Execution Network Monitors Network Management System


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Security Management Sub-Categories

and Related Activities (cont.)

Using Access

Control Methods

Encryption Packet filtering at routers Packet filtering at firewalls Source host authentication Source user authentication

Maintenance Audits of the activity at secure access points Executing security attack programs (Network Intrusion Detection) Detecting and documenting breaches

Accessing Public

Data Networks

No restrictions - hosts are responsible for securing all access points Limited access - only some hosts can interface with the Public DataNetwork using a proxy server

Using an Automated

Security Manager

Queries the configuration database to identify all access points for eachdevice. Reads event logs and notes security-related events. Security Manager shows a security event on the network map. Reports of invalid access point attempts are generated daily for analysis


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Functions of Security Management

The creation, deletion, and control of

security services and mechanisms.

The distribution of security-relevant

information.

The reporting of security-relevant events.


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(Confidentiality)

(Authentication)

(Integrity)

(Non-repudiation)

(Access control)

(Availability)


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1. Identifying the sensitive information to

be protected2. Finding the access points

3. Securing the access points

4. Maintaining the access points


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Access Point

A piece of network hardware or software

that allows access to the data network.

Software services Hardware components

Network media


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Securing the Access Points

(1). Packet Filtering

(2). Host Authentication

(3). User Authentication

(4). Key Authentication

(5). Encryption


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(1). Packet Filtering

Packet filtering usually can be performed inbridges, switches, and routers.

Packet filtering stops packets to or from

unsecured hosts before they reach an accesspoint.

Issues Each network device to perform packet filtering must

be configured. Packet filtering doesn't work if the unsecured host

changes its address.

Packet Filtering Routers


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Router with ACLs

Users

Users

ProtectedNetwork

E-mail

Server

Micro Webserver

zip 100

Micro Webserver

Web ServerPublicAccess

ISP andInternet

Packet-Filtering Routers


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(3). User Authentication

Enable service to identify each userbefore allowing that user access.

Password Mechanism Generally, passwords are transferred on the network without

any encryption.

Use encrypted passwords.

Users tend to make passwords easy to remember.

If the passwords are not common words, users will write themdown.

Host Authentication + User Authentication


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(4). Key Authentication

KeyA unique piece of information that authenticates the

data in a transaction.

Key Authentication The destination host requires the source host of a

transaction to present a key for the transaction.

Key ServerA server that validates requests for transactions

between hosts by giving out keys.

Source (S) Key Server (K) Destination (D)


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1. S requests remote login to D

2. S requests a key to K.

3. K validates the request.

4. K send a key to S.

5. S requests login with valid key to D.

S

S K

S K

K

S D


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Dear John:I am happy to know...


atek49ffdlffffeffdsfsfsff


plaintext plaintext

ciphertext ciphertextencryption decryption

(5). Encryption

Network


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Cryptography / Encryption

Encryption Encode, Scramble, or Encipher the plaintext information to

be sent.

EncryptionAlgorithm The method performed in encryption.

EncryptionKey A stream of bits that control the encryption algorithm.

Plaintext The text which is to be encrypted.

Ciphertext the text after encryption is performed.


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Encryption

Encryption Key


Plaintext

Encryption Algorithm


Ciphertext


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Decryption

Decryption Key


Plaintext

Decryption Algorithm


Ciphertext


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Encryption / Decryption


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Encryption Techniques

Private Key Encryption

Encryption Key = Decryption KeyAlso called Symmetric-Key Encryption, Secret-Key

Encryption, orConventional Cryptography.

Public Key Encryption

Encryption Key Decryption Key

Also calledAsymmetric Encryption

Private Key Encryption:


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Private Key Encryption:- DES (Data Encryption Standard)

Adopted by U.S. Federal Government.

Both the sender and receiver must know thesame secret key code to encrypt and decrypt

messages with DES Operates on 64-bit blocks with a 56-bit key

DES is a fast encryption scheme and works wellfor bulk encryption.

Issues: How to deliver the key to the sender safely?


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Other Symmetric Key Encryption Techniques

3DES

Triple DES

RC2, RC4 IDEA

International Data Encryption Algorithm

Key Size Matters!


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Key Size Matters!

Centuries

Decades

Years

Hours 40-bits

56-bits

168-bits*Triple-DES(recommended

for commercial

& corporate

information)Information

Lifetime

100s 10K 1M 10M 100M

Budget ($)


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Asymmetric Key in RSA

Key Length


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Symmetric Cipher

(Conventional)

Asymmetric

(RSA/D-H)

40 Bits 274 Bits

56 Bits 384 Bits64 Bits 512 Bits

80 Bits 1024 Bits

96 Bits 1536 Bits

112 Bits 2048 Bits

120 Bits 2560 Bits

128 Bits 3072 Bits

192 Bits 10240 Bits

Average Time for Exhaustive Key Search

32 Bits 2 = 4.3 X 1032 9

56 Bits 2 = 7.2 X 1056 16Number of

Possible Key128 Bits 2 = 3.4 X 10

128 38

Time required at

1 Encryption/uSEC

32 Bits ==> 2 usec =36 min31

56 Bits ==> 2 usec =1142 Years55

128 Bits ==> 2 usec =5X10 Years127 24

32 Bits ==> 2 millsec

56 Bits ==> 10 Hours

128 Bits ==> 5X10 Years18

Time required at

10 Encryption/uSEC6Performance

30~200 1

y g

Hybrid Encryption Technology:


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Hybrid Encryption Technology:PGP (Pretty Good Privacy)

Hybrid Encryption Technique First compresses the plaintext.

Then creates a session key, which is a one-time-only secret key.

Using the session key, apply a fast conventional encryptionalgorithm to encrypt the plaintext.

The session key is then encrypted to the recipients public key.

This public key-encrypted session key is transmitted along with the

ciphertext to the recipient.


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PGP Encryption


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PGP Decryption

The recipient uses its private key to

recover the temporary session key

Use the session key to decrypt theconventionally-encrypted ciphertext.


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PGP Decryption


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Digital Signatures

Digital signatures enable the recipient of

information to verify the authenticity of the

informations origin, and also verify that the

information is intact. Public key digital signatures provide

authentication

data integrity

non-repudiation

Technique: public key cryptography


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Simple Digital Signatures

S S


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Secure Digital Signatures

Maintaining the Secure Access


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Points

Locate potential and actual security

breaches.

Audit Trail

Security Test Programs

Att hi t P bli N t k


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Attaching to a Public Network

No Access

Full Access

All individual computers should have securitymanagement.

Limited Access

Use a firewall to enforce security betweenprivate and public networks.

(Fi ll)


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(Firewall)

Firewall

Firewall Packet Filtering Firewall

Dual-Homed Host Firewall

Screened Host Firewall

Screened Subnet Firewall

http://www.movies.acmecity.com/silent/6/doc/fwppt.zip

VPN (Vi t l P i t N t k)


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VPN (Virtual Private Network)

VPN:

VPN

X.25

Frame Relay

ATM Internet

VPN (Vi t l P i t N t k)


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VPN (Virtual Private Network)

VPN


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VPN

(Tunneling) IPSec (IP Security)

PPTP (Point-to-Point Tunneling Protocol)

L2TP (Layer 2 Tunneling Protocol)

(Encryption/Decryption) Private/Public/Hybrid Key Encryption

(Key Management) SKIP (Simple Key Management for IP)

IKE (ISAKMP/Oakley)

(Authentication) Username/Password + Token Number X.509 Certificate by Certificate Authority (CA)

Accounting Management (


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Accounting Management (

)

Accounting Management

Tracking each individual and group user's

utilization of network resources to betterensure that users have sufficient resources

Enable charges to be established for the use

of network resources, and the costs to be

identified for the use of those networkresources

Accounting Management Sub-


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Accounting Management Sub

Categories and Related ActivitiesGather Network Device

Utilization Data

Measure usage of resources by cost center Set quotas to enable fair use of resources Site metering to track adherence to software licensing

Bill Users of Network

Resources

Set charges based on usage. Measure one of the following

q Number of transactionsq Number of packetsq Number of bytes

Set charges on direction of information flow

Use and Accounting

Management Tools

Query usage database to measure statistics versusquotas Define network billing domains Implement automatic billing based on usage by usersin the domain Enable billing predictions Enable user selection of billing domains on the networkmap

Reporting Create historical billings trends Automatic distribution of billing to Cost Centers Project future billings by cost center

AM


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AM

Metrics

Measurement of network resources used.

QuotasThe amount of a network's resources allowed

for a user or group.

Billing

The process of charging users for the use ofthe data network and its associated services.


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One-Time Installation Fee and Monthly Fees

Fee Based on Amount of Network Resource

Consumed Total numbers of transactions

Total packets

Total bytes sent

Total bytes received

Fee Based on Amount of Time (For Dial-UpSerial Links)

}


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Monitor for any metrics that exceeds a

quota.

Store metric data into the database ofNMS.

Report the metric data that exceeds a

quota.

Use database's "trigger" ability to

automatically generate reports

()


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()

Perform network billing.

Determine where to poll for billing

information. Forecast the need of network resources

To establish reasonable metrics and quotas

To predict network billing cost for users

Generate accounting reports

Billing Process E ample


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Billing Process Example

1. Get network topology from DBMS

2. Get region user selected on networkmap

3. Determine devices in region4. Find devices to query (with the aids of

user's input).

5. Get billing information

6. Get pricing information

7. Get polling rate

8. Start performing queries and

calculations

Management Tools


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g

Management Tools (Cont.)


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g ( )

Management Tools (Cont.)


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Network Management


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g

Configurations

Centralized configuration

Management is centralized to the network

management station on the backbone

network

Distributed configuration

The LANs are managed by a local NMS while

an NMS host connects to the backbone

network


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Distributed Network


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Management

Probe = Remote Monitor

NMS = Network Management System

WS = Workstation

-------- = In-band or out-of band

management

communication

FIGURE 3-3 : Distributed Network Management

NMS

Probe

AgentWS

Agent

LAN 3 Node 3

Router

AgentNMS

Backbone

Router

AgentWS

Agent

Probe

Agent

LAN 2 Node 2

NMS

LAN 1

Node 1

Hub

AgentWS

Agent

Probe

Agent

Router

Agent

NMS

Selected Management Strategy


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Selected Management Strategy

ch3 network implementation

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