ITEC 275ITEC 275 Computer Networks – Switching, Computer Networks – Switching,

Routing, and WANsRouting, and WANs

Week 3Week 3Robert D’Andrea Robert D’Andrea

Winter 2016Winter 2016

AgendaAgenda

• Review• Learning Activities

– Analyzing an Existing Network– Analyzing Traffic in an Existing Network– QoS

• Introduce homework problems

What’s the Starting Point?What’s the Starting Point?• According to Abraham Lincoln:

– “If we could first know where we are and whither we are tending, we could better judge what to do and how to do it.”

Where Are We?Where Are We?When we characterize the infrastructure of

a network, we develop a set of network maps and locate major devices and network segments.

Developing a network map should involve understanding traffic flow, performance characteristics of network segments, and insight into where the users are concentrated and the level of traffic a network design must support. Everything you can think of to understand your customers network.

Where Are We?Where Are We?When characterizing our network, we

eventually want to visualize the whole infrastructure, but not at the same time. This is done by the use of layering of graphics displays.

Layers are simultaneous, over lapping components of an image or sequence. They are at work in many media software programs from Photoshop and Illustrator to audio, video, and animation tools, where multiple layers of image and sound (tracks) unfold in time.

Where Are We?Where Are We?The concept of layers comes from the

physical world, and it has a long history in the traditions of mapping and musical notation. Maps and time lines use overlapping layers to associate different levels of data, allowing them to contribute to the whole while maintaining their own identities.

Where Are We?Where Are We?Developing an understanding of your

customers existing network’s structure, involves it’s uses, and behavior, then you have a better chance of determining if you’re design goals are realistic.

Where Are We?Where Are We?• Characterize the existing internetwork in

terms of: – Its infrastructure

• Logical structure (modularity, hierarchy, topology)

• Physical structure

– Addressing and naming

– Wiring and media

– Architectural and environmental constraints

– Over all health of their network

How to Start?How to Start?• Characterization should start by using a top-

down approach.– Starting with a map or set of maps depicting a

high-level abstraction of information• Geographical information

• WAN

• WAN to LAN

• Buildings, floors, and wiring within the building

• Rooms containing servers, routers, mainframes, and switches

• Virtual information

How to Start?How to Start?• Characterizing large complex networks should reflect

influence from the OSI reference model. • A network map should depict applications and

services used by the network users.Internal and external web sitesEmail and external data access entriesFtp operationsPrinter and file sharing devicesDHCP, DNS, SNMPRouter interface names, firewalls, NAT, IDS, and IPS

How to Start?How to Start?Use tools that automate diagram representation of the network.

IBM’s Tivoli

What’s Up Gold from ipswitch

LAN surveyor

Microsoft Visio Professional

Network MapNetwork Map

Gigabit Ethernet

Eugene Ethernet20 users

Web/FTP server

Grants PassHQ

Gigabit Ethernet

FEP (Front End Processor)

IBMMainframe

T1

MedfordFast Ethernet

50 users

RoseburgFast Ethernet

30 usersFrame Relay

CIR = 56 KbpsDLCI = 5

Frame RelayCIR = 56 Kbps

DLCI = 4

Grants PassHQ

Fast Ethernet75 users

InternetT1

Characterize Large InternetworksCharacterize Large InternetworksDeveloping one map might be difficult to

do for a large internetwork. Many approaches might be needed for dissecting and understanding the problem.•Apply a top-down method influenced by the OSI reference model•Develop a series of maps (high (high level of abstraction) to low level)•Develop a logical map (shows applications, and services used by network users)

Characterize Large InternetworksCharacterize Large InternetworksDevelop a map of internal server functions:

Web

Email

sftp

Printing

File sharing

Characterize Large InternetworksCharacterize Large InternetworksDevelop a map of external server functions:

Web

Email

sftp

Mobile

Web caching servers on your map must be identified because they can affect your traffic flow.

Characterize Large InternetworksCharacterize Large InternetworksDevelop a map of network services:

• Terminal Access Controller Access Control System (TACACS) server(s)

• Remote Authentication Dial-In User Service (RADIUS) server(s)

• Dynamic Host Configuration Protocol (DHCP)• Domain Name System (DNS)• Simple Network Management Protocol (SNMP)• Location and reach of virtual private networks

(VPN)• Dial-in and dial-out servers• WAN• Internet

Characterize Large InternetworksCharacterize Large InternetworksDevelop a map of network services:

• Layer 3 topology of the internetwork (Cisco notation s0/0 ). This layer of information may reflect a network of devices from a single vendor or a mix of vendors.

• Protocols • Firewalls• NAT (Network Address Translation)• IDS (Intrusion Detection System)• IPS (Intrusion Prevention Detection)• Layer 2 devices• LAN devices and interfaces• Public and private WAMs

Characterize a Logical ArchitectureCharacterize a Logical Architecture• Determine the logical topology of the network. Is

the network flat, hierarchical, structured or unstructured, layered or not.

• Geometric shape of network (star, spoke, ring, or mesh)

• Look for ticking time bombs that could affect scalability. These are large layer 2 Spanning Tree Protocol (STP) domains that take excessive time to converge.

• Flat topologies do not scale as well as hierarchical topologies. This affects the ability to upgrade the network.

Flat Network Flat Network

Characterize a Logical ArchitectureCharacterize a Logical ArchitectureEnterprise CampusEnterprise Campus

Characterize a Logical ArchitectureCharacterize a Logical ArchitectureEnterprise EdgeEnterprise Edge

Characterize Addressing and NamingCharacterize Addressing and Naming• IP addressing for major network devices,

client, server, and private.

• Any addressing oddities, such as discontinuous subnets?

• Any strategies for addressing and naming?– Route summarization reduces routes in a router

– For example, sites may be named using airport codes

• San Francisco = SFO, Oakland = OAK

Networks NamesNetworks NamesWhat is a network name?

A network name is a text string that devices use to reference a particular computer network. These strings are, strictly speaking, separate from the names of individual devices and the addresses they use to identify each other. 

Networks NamesNetworks NamesWhat is a network name?

Wi-Fi networks support a type of network name called SSID. Wi-Fi access points and clients are each always assigned an SSID to help identify each other. When a person speaks of wireless network names, they typically are referring to SSIDs.

Microsoft Windows supports assigning PCs to named workgroups to facilitate peer-to-peer networking.

Networks NamesNetworks NamesAlternatively, Windows domains can be

used to segregate PCs into named sub-networks. Both Windows workgroup and domain names are set separately from the names of each PC and also function independently from SSIDs.

Yet another distinct form of network naming is sometimes used to identify computer clusters. Most server operating systems, for example, such as Microsoft Windows Server support independent naming of clusters.

Characterize Addressing and NamingCharacterize Addressing and Naming• Route summarization reduces routes in a

routing table, routing-table update traffic, and overall router overhead. Route summarization improves network stability and availability, because problems in one area of the network are less likely to affect the whole network.

• Dis-contiguous subnet is a subnet that has been divided into two areas.

Route SummarizationRoute Summarization

Dis-contiguous SubnetsDis-contiguous Subnets

Area 1Subnets 10.108.16.0 -

10.108.31.0

Area 0Network

192.168.49.0

Area 2Subnets 10.108.32.0 -

10.108.47.0

Router A Router B

Characterize Addressing and NamingCharacterize Addressing and Naming• Network addressing scheme might affect the

routing protocols. Some routing protocols do not support

Classless addressing

Variable-length subnet masking (VLSM)

Dis-contiguous subnets

Characterize the Wiring and MediaCharacterize the Wiring and Media• Single-mode fiber• Multi-mode fiber• Shielded twisted pair (STP) copper• Unshielded-twisted-pair (UTP) copper• Coaxial cable• Microwave• Laser• Radio• Infra-red

Characterize the Wiring and MediaCharacterize the Wiring and MediaDistance information is critical when

selecting data link layer technologies.It is helpful knowing how much copper

cable might need to be replaced if fiber cabling is to be used and if there is access for the replacement.

Determine the type of wiring used between the wiring closet, cross-connect rooms, and computer rooms.

Characterize the Wiring and MediaCharacterize the Wiring and MediaVertical wiring run between floors of a

buildingHorizontal wiring run from the wiring

closet to the wall plate in the office cubicles. Work-area wiring runs from the wall

plate to the workstation.in a cubicle.Generally, the distance from the wiring

closet to the workstation are approximately 100 meters.

Campus Network WiringCampus Network Wiring

TelecommunicationsWiring Closet

HorizontalWiring

Work-AreaWiring

Wallplate

Main Cross-Connect Room(or Main Distribution Frame)

Intermediate Cross-Connect Room(or Intermediate Distribution Frame)

Building A - Headquarters Building B

VerticalWiring

(BuildingBackbone)

CampusBackbone

Characterize the Wiring and Characterize the Wiring and MediaMedia

A time-domain reflectometer (TDR) is used to determine the distance of a cable. It is an electronic instrument that uses time-domain reflective technology to characterize and locate faults in metallic cables (for example, twisted-pair cable or coaxial cable)

Characterize the Wiring and MediaCharacterize the Wiring and MediaTDR

Architectural ConstraintsArchitectural Constraints• Make sure the following are sufficient

– Air conditioning

– Heating

– Ventilation

– Electrical power

– Protection from electromagnetic interference

– Door locking mechanism

– Environmental issues

– Too close to a right-of-way

Architectural ConstraintsArchitectural ConstraintsParameter Copper Twisted Pair MM Fiber SM Fiber Wireless

Distance Up to 100 meters Up to 2 kilometers (Fast Ethernet)Up to 550 m (Gigabit Ethernet)Up to 300 m (10 Gigabit Ethernet)

Up to 10 km (Fast Ethernet)Up to 5 km (Gigabit Ethernet)Up to 80 km (10 Gigabit Ethernet)

Up to 500 m at 1 Mbps

Bandwidth Up to 10 Gigabits per second (Gbps)

Up to 10 Gbps Up to 10 Gbps or higher

Up to 54 Mbps

Price Inexpensive Moderate Moderate to expensive

Moderate

Deployment Wiring closet Internode or interbuilding

Internode or interbuilding

Internode or interbuilding

Architectural ConstraintsArchitectural Constraints• Make sure there’s space for:

– Cabling conduits

– Patch panels

– Equipment racks

– Work areas for technicians to install and troubleshooting equipment

Wireless InstallationWireless Installation• Inspect the architecture and environment

constraints of the site to determining the feasibility of a wireless transmission.– Wireless transmission is RF (radio frequency)

– A wireless expert should be hired

– Network designers can install access point(s) where people tend to concentrate

– Signal loss occurs between the access point and the user of the access point.

Wireless InstallationWireless Installation• A wireless site survey is used to describe the

process of evaluating the a site to see if it will be appropriate for wireless transmission.

• An access point is likely to be placed in a location based on an estimate of signal loss that will occur between the access point and the users of the WLAN. An access point is a device that transmits and receives data for users on a WLAN. Generally, it is a point on interconnection between the WLAN and wired Ethernet network.

RF Phenomena Wireless InstallationsRF Phenomena Wireless Installations1. Reflection causes the signal to bounce back

on itself.2. Absorption occurs as the signal passes

through materials3. Refraction is when a signal passes through

one medium of one density and then through another medium of another density. Signal will bend.

4. Diffraction when a signal can pass in part through a medium more easily in one part than another

RF Phenomena Wireless InstallationsRF Phenomena Wireless Installations1. Reflection signal causes the signal to bounce back on itself. The signal can interfere with itself in the air and affect the receiver’s ability to discriminate between the signal and noise in the environment. Reflection is caused by metal surfaces such as steel girders, scaffolding, shelving units, steel pillars, and metal doors. Implementing a Wireless LAN (WLAN) across a parking lot can be tricky because of metal cars that come and go.

Reflective Wireless SignalReflective Wireless Signal

Reflective Wireless SignalReflective Wireless Signal

Reflective Wireless SignalReflective Wireless Signal

RF Phenomena Wireless InstallationsRF Phenomena Wireless Installations2. Some of the electromagnetic energy of the signal can be absorbed by the material in objects through which it passes, resulting in a reduced signal level. Water has significant absorption properties, and objects such as trees or thick wooden structures can have a high water content. Implementing a WLAN in a coffee shop can be tricky if there are large canisters of liquid coffee. Coffee-shop WLAN users have also noticed that people coming and going can affect the signal level. (On StarTrek, a non-human character once called a human “an ugly giant bag of mostly water”!)

Absorption Wireless SignalAbsorption Wireless Signal

RF Phenomena Wireless InstallationsRF Phenomena Wireless Installations3. Refraction is when an RF signal passes from a medium with one density into a medium with another density, the signal can be bent, much like light passing through a prism. The signal changes direction and may interfere with the non-refracted signal. It can take a different path and encounter other, unexpected obstructions, and arrive at recipients damaged or later than expected. As an example, a water tank not only introduces absorption, but the difference in density between the atmosphere and the water can bend the RF signal.

Reflective Wireless SignalReflective Wireless Signal

RF Phenomena Wireless InstallationsRF Phenomena Wireless Installations

4. Diffraction, which is similar to refraction, results when a region through which the RF signal can pass easily is adjacent to a region in which reflective obstructions exist. So, a signal can pass in part through a medium more easily in one part than another. Like refraction, the RF signal is bent around the edge of the diffractive region and can then interfere with that part of the RF signal that is not bent.

Diffraction Wireless SignalDiffraction Wireless Signal

RF Phenomena Wireless InstallationsRF Phenomena Wireless Installations• A wireless Site Survey should be performed

on the existing network for signal propagation, strength, and accuracy in different areas.– NIC cards ship with utilities on them to measure

signal strength– Signal strength can be determined using a protocol

analyzer– Access points send beacon frames every 100

milliseconds (ms). Use a protocol analyzer to analyze the signal strength being emitted from the different grid locations of the access points.

RF Phenomena Wireless InstallationsRF Phenomena Wireless Installations- Use a protocol analyzer to capture CRC

errors. These errors stem from corruption and collisions.

- Observe if frames are being lost in transmission

- Observe if acknowledgment (ACK) and frame retries after a missing ACK. ACK is called a control frame. Clients and access points use them to implement a retransmission mechanism

RF Phenomena Wireless InstallationsRF Phenomena Wireless Installations• Wired Ethernet

Detects collisions through CSMA/CD (802.11)

Ethernet uses CSMA/CA as the access method to gain access of the wire. An ACK control frame is returned to a sender for packet received. If a frame does not receive an ACK, it is retransmitted.

Check the Health of the Existing Check the Health of the Existing InternetworkInternetwork

• Baseline network performance with sufficient time and at a typical time

• Baseline availability gather information from the customer on MTBF and MTTR

• Baseline bandwidth utilization during a specific time frame. This is usually a percentage of capacity.

• Accuracy is an upper layer protocol’s responsibility. A frame with a bad CRC is dropped and retransmitted. A good threshold rule for handling errors is that there should be no more than one bad frame per megabyte of data.

Check the Health of the Existing Check the Health of the Existing InternetworkInternetwork

Accuracy is a measurement of lost packets. This measurement is achieved by keeping track of lost packets while measuring response time.

-Switches have replaced hubs.

- There should be fewer than 0.1 percent of frames encounter collisions.

- There should be no late collisions. Indicate bad cabling, cabling longer than 100 meters, bad NIC, or duplex mismatch.

Check the Health of the Existing Check the Health of the Existing InternetworkInternetwork

Auto-negotiation has received it’s share of criticism in the past for being inaccurate when setting up a point-to-point link half duplex and full duplex.

Auto-negotiation of speed is usually not a problem. If set up incorrectly, it does not work. The speeds are 10 Mbps, 100 Mbps, or 1000 Mbps.

Check the Health of the Existing Check the Health of the Existing InternetworkInternetwork

Category 3 cable will support 10MBps, but not 100 MBps and higher. Errors increase.•Efficiency is linked to large frame sizes. Bandwidth utilization is optimized for efficiency when applications and protocols are in large sized frames.

– Change window sizes on clients and servers. Increasing maximum transmission unit (MTU).

– Able to ping and telnet but not be able to send HTTP, and FTP.

– A hump exist on the sides of the average transmission.– Runt frames (less than 64 bytes) are a result of

collisions on the same shared Ethernet segment.

Check the Health of the Existing Check the Health of the Existing InternetworkInternetwork

• Response time can be measured using the round-trip time (RTT) ping command. Observe response time on a user workstation. Run typical applications to

get a response.Response time for network services protocols, such as, DHCP and DNS.

• Status of major routers, switches, and firewalls

Characterize AvailabilityCharacterize Availability

Enterprise

Segment 1

Segment 2

Segment n

MTBF MTTRDate and Duration of Last Major Downtime

Cause of Last Major Downtime

Fix for Last Major Downtime

Network Utilization

0 1 2 3 4 5 6 7

17:10:00

17:07:00

17:04:00

17:01:00

16:58:00

16:55:00

16:52:00

16:49:00

16:46:00

16:43:00

16:40:00

Tim

e

Utilization

Series1

Network Utilization in Minute IntervalsNetwork Utilization in Minute Intervals

Network Utilization

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5

17:00:00

16:00:00

15:00:00

14:00:00

13:00:00

Tim

e

Utilization

Series1

Network Utilization in Hour IntervalsNetwork Utilization in Hour Intervals

Bandwidth Utilization by ProtocolBandwidth Utilization by Protocol

Protocol 1

Protocol 2

Protocol 3

Protocol n

Relative Network Utilization

Absolute Network Utilization

Broadcast Rate

Multicast Rate

Characterize Packet SizesCharacterize Packet Sizes

Characterize Response TimeCharacterize Response Time

Node A

Node B

Node C

Node D

Node A Node B Node C Node D

X

X

X

X

Check the Status of Major Routers, Check the Status of Major Routers, Switches, and FirewallsSwitches, and Firewalls

• Show buffers

• Show environment

• Show interfaces

• Show memory

• Show processes

• Show running-config

• Show version

Check the Status of Major Routers, Check the Status of Major Routers, Switches, Hubs, and FirewallsSwitches, Hubs, and Firewalls

Hubs (bit cloning machine)

Span every connection on a hub

Cheap

Wasteful of bandwidth

Sends replicated packet data on all ports

When monitoring (Wireshark) a network, see redundant traffic

Check the Status of Major Routers, Check the Status of Major Routers, Switches, and FirewallsSwitches, and Firewalls

Switches

Less complicated than routers

Used for Ethernet and Wi-Fi medium based on MAC address (burnt on NIC)

Initially, a switch table is empty. Broadcasts on all ports until all port connections are discovered.

Switch uplink port can be used to connect to router(s).

Switches deliver packets directly to the correct destination without spanning all port connections.

Check the Status of Major Routers, Check the Status of Major Routers, Switches, and FirewallsSwitches, and Firewalls

Switch tableInterface MAC Addresses

1 AA-AA-AA-AA-AA-AA

2 CC-CC-CC-CC-CC-CC

3 DD-DD-DD-DD-DD-DD

Check the Status of Major Routers, Check the Status of Major Routers, Switches, and FirewallsSwitches, and Firewalls

Router

Routers connect networks

Support NAT and DHCP

Utilize the IP protocol

Internal Ethernet switch built-in

Check the Status of Major Routers, Check the Status of Major Routers, Switches, and FirewallsSwitches, and Firewalls

Hubs, Switches, and Routers

Each of these devices operates at a different layer.

Network IP protocol194.78.0.163

Link Medium over which the packet is traveling. Ethernet and Wi-Fi . MAC Address01-DE-89-0A-77-BB

Physical Raw 01001000111100…

ToolsTools• Protocol analyzers

• Multi Router Traffic Grapher (MRTG)

• Remote monitoring (RMON) probes

• Cisco Discovery Protocol (CDP)

• Cisco IOS NetFlow technology

• CiscoWorks

Network Traffic FactorsNetwork Traffic Factors• Traffic flow

• Location of traffic sources and data stores

• Traffic load

• Traffic behavior

• Quality of Service (QoS) requirements

User CommunitiesUser CommunitiesUser Community Name

Size of Community (Number of Users)

Location(s) of Community

Application(s) Used by Community

Data StoresData StoresData Store Location Application(s) Used by User

Community(or Communities)

Traffic FlowTraffic Flow

Destination 1 Destination 2 Destination 3 Destination MB/sec MB/sec MB/sec MB/sec

Source 1

Source 2

Source 3

Source n

Traffic Flow Traffic Flow ExampleExample

Administration

Business and Social Sciences

Math and Sciences

50 PCs 25 Macs50 PCs

50 PCs30 PCs

30 Library Patrons (PCs) 30 Macs and 60 PCs in Computing Center

Library and Computing Center

App 1 108 KbpsApp 2 60 KbpsApp 3 192 KbpsApp 4 48 KbpsApp 7 400 KbpsTotal 808 Kbps

App 1 48 KbpsApp 2 32 KbpsApp 3 96 KbpsApp 4 24 KbpsApp 5 300 KbpsApp 6 200 KbpsApp 8 1200 KbpsTotal 1900 Kbps

App 1 30 KbpsApp 2 20 KbpsApp 3 60 KbpsApp 4 16 KbpsTotal 126 Kbps

App 2 20 KbpsApp 3 96 KbpsApp 4 24 KbpsApp 9 80 KbpsTotal 220 Kbps

Arts and Humanities

Server Farm

10-Mbps Metro Ethernet to Internet

Types of Traffic FlowTypes of Traffic Flow

• Terminal/host

• Client/server

• Thin client

• Peer-to-peer

• Server/server

• Distributed computing

Traffic Flow for Voice over IPTraffic Flow for Voice over IP• The flow associated with transmitting

the audio voice is separate from the flows associated with call setup and teardown. – The flow for transmitting the digital voice is

essentially peer-to-peer.

– Call setup and teardown is a client/server flow

• A phone needs to talk to a server or phone switch that understands phone numbers, IP addresses, capabilities negotiation, and so on.

Network ApplicationsNetwork ApplicationsTraffic CharacteristicsTraffic Characteristics

Name of Application

Type of Traffic Flow

Protocol(s) Used by Application

User Communities That Use the Application

Data Stores (Servers, Hosts, and so on)

Approximate Bandwidth Requirements

QoS Requirements

Traffic LoadTraffic Load• To calculate whether capacity is sufficient, you

should know:– The number of stations– The average time that a station is idle between

sending frames– The time required to transmit a message once

medium access is gained

• That level of detailed information can be hard to gather, however.

Size of Objects on NetworksSize of Objects on Networks• Terminal screen: 4 Kbytes

• Simple e-mail: 10 Kbytes

• Simple web page: 50 Kbytes

• High-quality image: 50,000 Kbytes

• Database backup: 1,000,000 Kbytes or more

Traffic BehaviorTraffic Behavior• Broadcasts

– All ones data-link layer destination address• FF: FF: FF: FF: FF: FF

– Doesn’t necessarily use huge amounts of bandwidth

– But does disturb every CPU in the broadcast domain

• Multicasts– First bit sent is a one

• 01:00:0C:CC:CC:CC (Cisco Discovery Protocol)

– Should just disturb NICs that have registered to receive it

– Requires multicast routing protocol on internetworks

Network EfficiencyNetwork Efficiency

• Frame size

• Protocol interaction

• Windowing and flow control

• Error-recovery mechanisms

Network EfficiencyNetwork Efficiency

Network utilization is the measurement of the amount of bandwidth that is used during a specific time interval. The measure is expressed in terms of percentage of capacity. Seventy percent (70%) is considered a reasonable level for normal link traffic.

QoS RequirementsQoS Requirements• ATM service specifications

– Constant bit rate (CBR)

– Realtime variable bit rate (rt-VBR)

– Non-realtime variable bit rate (nrt-VBR)

– Unspecified bit rate (UBR)

– Available bit rate (ABR)

– Guaranteed frame rate (GFR)

QoS Requirements per IETFQoS Requirements per IETFInternet Engineering Task Force (IETF)

•IETF integrated services working group specifications

– Controlled load service• Provides client data flow with a QoS closely

approximating the QoS that same flow would receive on an unloaded network

– Guaranteed service• Provides firm (mathematically provable) bounds on

end-to-end packet-queuing delays

QoS Requirements per IETFQoS Requirements per IETF

• IETF Differentiated Services working group specifications

• RFC 2475– IP packets can be marked with a Differentiated

Services Code Point (DSCP) to influence queuing and packet-dropping decisions for IP datagrams on an output interface of a router.

SummarySummary

• Characterize the existing internetwork before designing enhancements.

• Helps you verify that a customer’s design goals are realistic.

• Helps you locate where new equipment will be placed.

• Helps you cover yourself if the new network has problems due to unresolved problems in the old network.

SummarySummary

• Continue to use a systematic, top-down approach

• Don’t select products until you understand network traffic in terms of:– Flow

– Load

– Behavior

– QoS requirements

Review QuestionsReview Questions

• What factors will help you decide if the existing internetwork is in good enough shape to support new enhancements?

• When considering protocol behavior, what is the difference between relative network utilization and absolute network utilization?

• Why should you characterize the logical structure of an internetwork and not just the physical structure?

• What architectural and environmental factors should you consider for a new wireless installation?

Review QuestionsReview Questions

• List and describe six different types of traffic flows.

• What makes traffic flow in voice over IP networks challenging to characterize and plan for?

• Why should you be concerned about broadcast traffic?

• How do ATM and IETF specifications for QoS differ?

This Week’s OutcomesThis Week’s Outcomes

• Characterize the Existing Network• Analyzing Traffic in an Existing Network• Determine QoS• Wireless Signals

Due this weekDue this week

• 2-1 – Concept questions 2

Next weekNext week

• 3-1 – Concept questions 3• FranklinLive session 4• Ensure you have the VMware View Client

installed• Examine the MIMIC simulator software

Q & AQ & A

• Questions, comments, concerns?