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