Exam 3

WAN Design - high traffic

- (10-50 Mbps) -Ethernet, IP, or MPLS -T3

WAN Design - low to moderate traffic

- (<10 Mbps) -VPN over internet -Frame Relay

WAN Design - very high traffic

- (>50 Mbps) -Ethernet, IP, MPLS -SONET

Characteristics of Dedicated-Circuit Networks

-CSU and/or DSU -circuit established between 2 communicating devices -Ethernet frame/ IP packet is translated to layer 2/ layer 3 protocol used by the WAN -SONET and T-Carrier

Types of WAN

-Dedicated-Circuit Networks -Packet-Switched Networks

Carriers offering packet-switched services usually charge for different items. What are some examples?

-Permanent virtual circuit (PVC) -Committed information rate (CIR) -Maximum allowable rate (MAR)

Stuxnet

-a complex worm that was discovered in 2010 by Kaspersky Lab -contained four zero days targeting Windows vulnerabilities

Python

-a high-level programming language that allows for rapid development of applications -created based on C and C++, this allows it to have great functionality which allows it to be integrated with other programs

What is an example of a WAN service?

-dedicated circuit service -packet switched services -VPN over public internet

What is the function of a router?

-determining a path for a packet to travel over -Transmitting the packet across a path -Translating between different devices and protocols

What are the benefits of a VLAN?

-enabling networks to be managed by functional workgroups -better control over broadcast messages -enhanced security

traditional network design process

-follows a very structured system analysis and design process - a precise estimate of the amount of data that each user will send and receive is developed -the suggested circuits must support the estimated traffic plus a modest increase in traffic

Characteristics of user Privileged EXEC mode

-i.e. router>enable router# -change hostname of the router -adding a password -see the running-configuration fo the router & more

IPC socket

-is one endpoint of a communication channel used by programs to pass data back and forth locally or across the Internet

Characteristics of Switched-Circuit Networks

-multiple connections exist simultaneously between devices - PAD (packet assembly/disassembly device) -Ethernet frame/ IP packet is translated to Layer 2/ Layer 3 protocol is used by the WAN -Different locations have different speeds (POP & PVC)

Characteristics of user EXEC mode

-you'll see > at the command prompt -no configurations are done -only to view configurations of router

Public Class A

0-126

OC-24

1.244 Gbps

T1 (basic telephone line)

1.544 Mbps

Private Class A

10.0.0.0

The most commonly installed wired Ethernet these days is:

100Base-T or 1000Base-T over Cat 5e

An example of the expected data rate on a 100Base-T network

100Mbps

An IPv6 address is a ___________ bit address.

128

Public Class B

128-191

Private Class B

172.16.0.0-172.31.255.255

Public Class C

192-223

Private Class C

192.165.0.0-192.165.255.255

Refer to the figure above. How many different braodcast domains are on this network?

2

T3

44.376 Mbps

OC-1

51.88 Mbps

Refer to the figure. How many colision domains are on this network?

8

Which file on the router defines what types of packets should be routed and what types of packets should be discarded?

Access Control List (ACL)

What are the 3 layers, also the first 3 components, of the network architecture?

Access, Distribution , and Core Layers

You have been assigned to manage the 802.11ac wireless network where each access is connected to it's own individual router. How should the wireless channels be configured on Access Points A, B, and C?

All access points should use different channels

what is the proper placement of the organization's servers

All servers should be in the organization's data center

Refer to the figure above. There are two servers to this network. If you had used a good LAN and Backbone design, which two computers on this network are the servers? (3)

Any two cmputers on the switch A.

Why is designing circuits for WAN more difficult than for LAN?

Because LAN circuits come in standard sizes ( 100Mbps or 1 Gbps). This is not true for WAN circuits that offer many more choices in standard sizes and it is much more difficult to estimate circuit loading for many users that it is for one user.

Some countries, like China, don't allow users to connect to certain Internet services, such as Facebook. However, if you use a VPN connection to your university/company, you are able to connect to Facebook. Why does this happen?

Because using VPN, the IP destination address will be your university's IP address rather than Fecebook's IP address.

What are the parts that make up a router?

CPU, Memory (volatile and nonvolatile), ports

Your company decided to use dedicated-circuit services for its WAN. What device will be installed at all premises that will be connected in the WAN?

CSU/DSU

There are two common options when purchasing Internet connection for your home - DSL or Cable. What is the main difference between these two services?

Cable is a chared multipoint circuit, while DSL is a point-to-point circuit.

What is a false statement about the 802.11ac wireless network communication.

Clients use CSMA/CS communication

Router(config)#line vty 0 4

Configure virtual terminal lines

Which port is used to set up the router for the first time?

Console port

Router(config)#login

Enable password checking at login

Router(config)# enable secret letmeinletmein

Enable secret password (letmeinletmein) in the privileged EXEC mode

Router> enable

Enter Privileged EXEC mode; all commands to configure router

Router# config t

Enter global configuration mode

(T or F) A switched backbone,that uses layer-2 switches, has less broadcast traffic than a VLAN based backbone.

False

What services is the oldest, and slowly retiring, packet-switching service?

Frame Relay

What WAN topology provides the highest availabiltiy and the greatest cost?

Full Mesh

Which operating system is used most freqeuntly (90% of the time) on a router?

IOS

What protocol is used to encapsulate the VPN data if we use layer 3 VPN software?

IPSec

Zero day Vulnerability

Is a vulnerability that the owner of the software is not aware of

Which of the following services is not a dedicated-circuit service?

MPLS

Your company decided to go with packet-switched services for its WAN infrastructure. What device will be installed at all premises that will be connected to the WAN using this service?

PAD

Router(config-if)# ip address 25.23.136.1 255.0.0.0

Setup IP address on a port

Router(config)# banner login % Just Kidding %

Setup banner message

Router(config)# hostname SpaceMan

Setup new hostname (new name for the router)

Router(config)#password dontwritemedown

Setup password on virtual terminal lines

Router(config)# ip route 23.0.0.0 255.0.0.0 fastEthernet 0/1

Setup static router

Router# show running-config

Show running configuration of the router

When a frame arrives at a switch, what is stored from it along with the port it came in on?

Source MAC address

Which statement about switched backbone is best?

Switched backbones are commonly used to connect LANs inside a building.

What are the WAN services to require translation or encapsulation into a new protocol?

T-Carrier, SONET, Frame Relay

Selecting the best WAN service depends on the data rates you anticipate between different campuses. Suppose, that your data rates will be very high because you need to move large data files across the network. Which of the following services would not meet your needs?

T1

ABC Dollar is a growing retail store chain with 500 stores across the US. Most stores are relatively small stores located in small towns. The network will be used for real-time inventory updates and credit card transactions. What WANs would you recommend?

T3, Ethernet Services, IP Services

Now assume that in the figure above, all computers are client computers and there is a circuit from the router to the Internet.

The client computers on the hub would experience about he same throughput from the internet as clients on the switch C

What do OC-1 and T3 have in common?

They offer about the same data rate (44.376 Mbps and 51.84 Mbps)

Router#

This is the privileged EXEC mode

In the figure above, users on the network want to use mobile devices and you need to install two access points. Following the good LAN and Backbone design, where should you plug in these two access points?

To the switch C5

(T or F) The key concept in the building-block process is that using few standard components throughout the network is cheaper in the long run than to use a variety of different components to build different parts of the network.

True

(T or F) A Request for Proposal (RFP) specifies what equipment, software, and services are desired and asks vendors to provide their best prices.

True

(T or F) VLAN switches are a special conbination of layer-2 switches and routers.

True

(T or F) VLANs are networks in which computers are assigned to LAN segments by software rather than by hardware.

True

Router(config-if)#no shut

Turn interface UP

Router>

User EXEC mode; only non-destructive commands

McWansey & Company is a consulting firm with offices in five cities across upstate New York. A typical office has 5-7 employees. The network will typically be used to exchange Word and PPT files. What WAN would you recommend?

VPN over DSL

what are the 3 components of the network architecture that make up the enterprise edge?

WAN, Internet Access, E-Commerce Edge

Suppose you bring your laptop into a room with a 802.11ac wireless access point running at 300 Mbps that is connected into a 100Base-T switch which leads to the backbone. Your friend has connected her laptop via a Cat 5 cable to the switch. If you are the only computer using the AP:

Your throughput will be about the same as hers

Suppose you bring your laptop into a room with a 802.11ac wireless access point running at 300 Mbps that is connected into a 100Base-T switch which leads to the backbone. Your friend has connected her laptop via a Cat 5 cable to the switch. If there are 20 computers using the AP:

Your throughput will be slower than hers

The main output of the needs analysis is:

a logical network design

Worms

a type of malware that replicates itself in order to spread from computer to computer

another term to describe the core layer is:

campus backbone

3 Technologies apart of the access layer

hub, switch, access point

Your boss asks you to explain why you purchased switches instead of the cheaper hubs -- he heard that they do the same thing. What do you tell him to justify the purchases of the switches?

hubs share network capacity with all users so they are slower than switches

What is not a benefit of a VLAN?

improvement of physical layout

WAN topologies

ring, star, full-mesh, partial-mesh

a technology that is not apart of the access layer (LAN)?

router

What does a Request for Proposal (RFP) specify?

specifies what equipment, software, and services are desire and asks vendors to provide their best prices.

Switched Ethernet has a ___________ logical topology and a ____________ physical layer

star, star

What is NOT true about the traditional network design process?

the process is cheap and fast

What are the 2 modes of a router?

user EXEC and user Privileged EXEC