Network + Flash Cards
The _____ command is used in a Windows environment to see how many
hops a packet takes to reach a destination
tracert
The communication between distance-vector routers is known as ____
Hops
the largest data unit that can be passed without fragmentation.
The Maximum Transmission Unit (MTU)
The process by which routers learn of a change in the network
topology is called
convergence
The second version of RIP dealt with the shortcomings of the
original design. Authentication was included to enable secure transmissions,
also, it changed from a networkwide broadcast discovery method
to a multicast method to reduce overall network traffic.
RoutingInformation Protocol or
RIPv2
The syntax for the route add command is:
route add 192.168.2.1
mask (255.255.255.0) 192.168.2.4
Three types of bridges are used in networks:
Transparent bridge
Source route bridge
Translational bridge
Unlike cut-through, in a _____ switching
environment, the entire packet is received and error-checked before
being forwarded. The upside of this method is that errors are not propagated
through the network. The downside is that the error-checking
process takes a relatively long time, and store-and-forward switching is
considerably slower as a result..
store-and-forward
used with network bridges and switches. With the help of Spanning Tree Algorithm (STA), STP avoids or eliminates loops on a Layer 2 bridge.
Spanning Tree Protocol (STP)
What are the methods of switching?
Cut-through
Store-and-forward
FragmentFree
What are the two types of Link-state protocols?
Open Shortest Path First (OSPF)
Intermediate System-to-Intermediate System (IS-IS):
WHat is one waya router that uses Link-state protocol differs fromone that uses distance-vector protocol
it builds a map of the entire network and then
holds that map in memory. ALso, On a network that uses a link-state protocol,
routers send link-state advertisements (LSAs) that contain information about
the networks to which they connect.
What two issues must be considered when using bridges?
Bridge Placement and Eliminating bridging loops
With _____ communications, each router on the network
communicates all the routes it knows about to the routers to which it is
directly attached. In this way, routers communicate only with their router
neighbors and are unaware of other routers that may be on the network.
Distance-Vector Routing
With eliminating bridging loops: Bridging loops can occur when more than
one bridge is implemented on the network. In this scenario, the bridges
can confuse each other by leading one another to believe that a device is
located on a certain segment when it is not. To combat the bridging
KNOW THIS
____enables administrators to monitor the traffic outbound and inbound
to the switch.
Port mirroring
The ports on a hub to which computer systems are attached are called
Medium-Dependent Interface Crossed (MDI-X).
Another type of port, called a_____port, is often
included on a hub or switch to facilitate the connection of two switches or
hubs.
Medium-Dependent Interface (MDI)
ExamAlert
In a crossover cable, wires 1 and 3 and wires 2 and 6 are crossed.
ExamAlert
Routers that send link-state advertisements (LSA) that contain information about the network to which they connect
link-state routing
- True or False: The biggest difference between a LAN and WAN is usually
the size of the network.
- True. A WAN is a network that spans more than one geographic location,
often connecting separated LANs.
- What network model offers no centralized storage of data or centralized
control over the sharing of files or resources?
- A peer-to-peer network is a decentralized network model offering no centralized
storage of data or centralized control over the sharing of files or
resources.
- In what networking model is the processing power shared between the
client systems and the server?
- A distributed network model has the processing power distributed
between the client systems and the server.
A___ is a data network restricted to a single geographic location and typically
encompasses a relatively small area, such as an office building or school
LAN
A ____is a network that spans more than one geographic location, often
connecting separated LANs
WAN
You can choose from two basic wired network models:
peer-to-peer and
client/server.
A ____network is a decentralized network model offering no centralized
storage of data or centralized control over the sharing of files or
resources. All systems on this network can share the resources on
their local computer and use resources of other systems.
peer-to-peer
The ____ networking model is, without question, the most widely
implemented model and the one you are most likely to encounter when working
in real-world environments. The advantages of the this system
are that it is a centralized model and it enables centralized network management
of all network services, including user management, security, and backup
procedures
The client/server
EXAM ALERT:
The role of the client computer in the client/server model is to request the data
from the server and present that data to the users.
EXAM ALERT
1. What is the maximum number of computers recommended for inclusion in a peer-to-peer network? ❍ A. 2 ❍ B. 5 ❍ C. 10 ❍ D. 25
- C. The maximum number of computers recommended in a peer-to-peer network
is 10.
2. When a WAN is confined to a certain geographic area, such as a university campus or city, it is known as a ❍ A. LAN ❍ B. MAN ❍ C. VAN ❍ D. VPN
- B. A WAN can be referred to as a MAN (Metropolitan Area Network) when it is
confined to a certain geographic area, such as a university campus or city.
- Which topology (star, bus, or ring) would use a hub or switch?
- Of the choices given, only a star topology would use a hub or switch.
- With which topology does every node have a direct connection to every
other node?
- With a mesh topology, every node has a direct connection to every other
node.
A ___refers to a network’s physical and logical layout.
topology
A network’s____topology refers to the actual layout of the computer cables and other network
devices.
physical
A network’s_____ topology refers to the way in which the network
appears to the devices that use it.
logical
A___ topology uses a trunk or backbone to connect all the computers on the
network
bus
EXAM ALERT:
Loose or missing terminators from a bus network disrupt data transmissions.
EXAM ALERT:
Loose or missing terminators from a bus network disrupt data transmissions.
The____ topology is actually a logical ring, meaning that the data travels in a
circular fashion from one computer to another on the network.
ring, is not a physical ring
In the ____topology, all computers and other network devices connect to a central
device called a hub or switch. Each connected device requires a single cable
to be connected to the hub, creating a point-to-point connection between the
device and the hub.
star
Among the network topologies discussed in this chapter, the star topology is the
easiest to expand in terms of the number of devices connected to the network.
EXAM ALERT
The ___ ____ topology (see Figure 1.6) incorporates a unique network design
in which each computer on the network connects to every other, creating a
point-to-point connection between every device on the network
wired mesh
EXAM ALERT:
Because of the redundant connections, the mesh topology offers better fault tolerance
than other topologies.
EXAM ALERT:
Because of the redundant connections, the mesh topology offers better fault tolerance
than other topologies.
___ ___ ___is a technology designed to speed up network
traffic flow by moving away from the use of traditional routing tables.
Multiprotocol Label Switching (MPLS)
Wireless networks typically are implemented using one of two wireless topologies:
. Infrastructure, or managed, wireless topology
. Ad hoc, or unmanaged, wireless topology
The ___ ___ ___ is commonly used to extend a wired LAN to
include wireless devices. Wireless devices communicate with the wired LAN
through a base station known as an access point (AP) or wireless access point.
infrastructure wireless topology
In a __ __ __ topology, devices communicate directly between themselves
without using an access point. This peer-to-peer network design is commonly
used to connect a small number of computers or wireless devices.
wireless ad hoc
Wireless mesh networks are known as self-healing, which
refers to the network’s capability to adapt to network failure and even
function should a node be moved from one location to another. Selfhealing
in a wireless mesh environment is possible because of the interconnected
connections and because of the wireless media.
Self-healing
Another meaning: The term hybrid topology also can refer to the combination of
wireless and wired networks. For the Network+ exam, however, the term hybrid
most likely refers to the combination of physical networks.
EXAM ALERT
- You have been asked to install a network to give the network users the greatest
amount of fault tolerance. Which of the following network topologies would you
choose?
❍ A. Star
❍ B. Ring
❍ C. Mesh
❍ D. Bus
- C. A mesh network uses a point-to-point connection to every device on the network.
This creates multiple points for the data to transmit around the network
and therefore creates a high degree of redundancy. The star, ring, and bus
topologies do not offer fault tolerance.
An AP can operate as a bridge connecting a standard wired network to wireless
devices or as a router passing data transmissions from one access point to
another.
EXAM ALERT
The term ___ ____ is used to loosely encompass any device capable of
encrypting data for the purpose of making it more difficult to intercept. On
the lower end, this can encompass devices used by individual users (encrypted
flash drives, for example). On the higher end, a server can encrypt data for the
network.
encryption devices
Because the Network+ exam focuses on networking and the objective focuses on
the OSI model, the presentation layer is responsible for encrypting/decrypting data
EXAM ALERT:
Because the Network+ exam focuses on networking and the objective focuses on
the OSI model, the presentation layer is responsible for encrypting/decrypting data
sent across the network.
EXAM ALERT:
Because the Network+ exam focuses on networking and the objective focuses on
the OSI model, the presentation layer is responsible for encrypting/decrypting data
sent across the network.
- Users are complaining that the network’s performance is unsatisfactory. It takes
a long time to pull files from the server, and, under heavy loads, workstations
can become disconnected from the server. The network is heavily used, and a
new videoconferencing application is about to be installed. The network is a
1000BaseT system created with Ethernet hubs. Which device are you most likely
to install to alleviate the performance problems?
❍ A. Switch
❍ B. Router
❍ C. Bridge
❍ D. Gateway
- A. Replacing Ethernet hubs with switches can yield significant performance
improvements. Of the devices listed, switches are also the only ones that can be
substituted for hubs. A router is used to separate networks, not as a connectivity
point for workstations. A bridge could be used to segregate the network and
therefore improve performance, but a switch is a more obvious choice in this
example. A gateway is a device, system, or application that translates data from
one format into another.
2. Which of the following devices forwards data packets to all connected ports? ❍ A. Router ❍ B. Switch ❍ C. Bridge ❍ D. Hub
- D. Hubs are inefficient devices that send data packets to all connected devices.
Switches pass data packets to the specific destination device. This method significantly
increases network performance.
3. Of the following routing methods, which is likely to require the most administration time in the long term? ❍ A. Static ❍ B. Link state ❍ C. Distance vector ❍ D. Dynamic
- A. Static routing takes more time to administer in the long term because any
changes to the network routing table must be manually entered. Distance vector
and link state are both dynamic routing methods. Dynamic routing might take
more time to configure initially, but in the long term, it requires less administration
time. It can automatically adapt to changes in the network layout.
- Which of the following statements best describes a gateway?
❍ A. It is a device that enables data to be routed from one network to
another.
❍ B. It refers to any device that resides at the entrance of a network.
❍ C. It is a device, system, or application that translates data from one format
into another.
❍ D. It is a network device that can forward or block data based on the
MAC address embedded in the packet.
- C. A gateway can be a device, system, or application that translates data from
one format into another. Answers A and B more closely describe a router.
Answer D describes a bridge. A bridge is a device that is used to segregate a
network. It makes forwarding or blocking decisions based on the MAC address
embedded in the packet.
- You are experiencing performance problems on your Ethernet-based network. By
using a network performance-monitoring tool, you determine that the network
has a large number of collisions. To reduce the collisions, you decide to install a
network bridge. What kind of bridge are you most likely to implement?
❍ A. Collision bridge
❍ B. Transparent bridge
❍ C. Visible bridge
❍ D. Translational bridge
- B. A transparent bridge can be used to segment a network, reducing the number
of collisions and overall network traffic. It is called transparent because the other
devices on the network do not need to be aware of the device and operate as if
it weren’t there. A translational bridge is used in environments where it is necessary
to translate one data format into another. Such a conversion is unnecessary
in this scenario. There is no such thing as a collision bridge or a visible bridge.
- What acts as a translator between the LAN and WAN data formats?
- A CSU/DSU acts as a translator between the LAN and WAN data formats.
- What is the term that describes the mechanisms used to control bandwidth
usage on the network?
- Bandwidth shaping describes the mechanisms used to control bandwidth
usage on the network.
- True or False: A load balancer must be a hardware device specially configured
to balance the load.
- False. A load balancer can be either a hardware device or software specially
configured to balance the load.
The term ___ ___ describes the mechanisms used to control bandwidth
usage on the network. With this, administrators can control who uses bandwidth,
for what purpose, and what time of day bandwidth can be used. Traffic
shaping establishes priorities for data traveling to and from the Internet and
within the network.
traffic shaping
A ___ ___ essentially performs two key
functions—monitoring and shaping. Monitoring includes identifying where
bandwidth usage is high and the time of day. After that information is
obtained, administrators can customize or shape bandwidth usage for the best
needs of the network.
bandwidth shaper
A ___ ___ is any software that controls what a user is allowed to peruse
and is most often associated with websites. Using a content filter, an employer
can block access to pornographic sites to all users, some users, or even just an
individual user.
content filter
___ ___ is a technique in which the workload is distributed between several servers. This feature can
take networks to the next level; it increases network performance, reliability,
and availability.
Load balancing
EXAM ALERT:
Remember that load balancing increases redundancy and therefore data availability.
Also, load balancing increases performance by distributing the workload.
EXAM ALERT
A ___ ___ is one that can operate at both Layer 2 and Layer 3 of the
OSI model, which means that the multilayer device can operate as both a
switch and a router.
multilayer switch
EXAM ALERT:
A multilayer switch operates as both a router and a switch.
EXAM ALERT
A ___ ___ examines the
network data it receives, decides where the content is intended to go, and forwards
it. It can also can identify the application that data is targeted
for by associating it with a port.
content switch
___ ___ can help with load balancing because they can distribute
requests across servers and target data to only the servers that need it, or distribute
data between application servers.
Content servers
EXAM ALERT:
A content switch can distribute incoming data to specific application servers and
help distribute the load.
EXAM ALERT
a __ __ is defined as a server that sits between a client computer and the
Internet, looking at the web page requests the client sends.
proxy server
The ___ is a list of
allowed or nonallowed websites;
Access Control List (ACL)
A ___ ___ can be used to increase remote-access security. It can establish a secure connection (tunnel)
between the sending and receiving network devices.
VPN concentrator/ VPN concentrators
add an additional level to VPN security. They can not only create the tunnel,
but they also can authenticate users, encrypt the data, regulate the data transfer,
and control traffic.
Connects networks
Router- A router uses the softwareconfigured
network address to
make forwarding decisions.
Connects LANS to reduce overall network traffic
Bridge- A bridge enables data to pass through it or prevents data from passing through it by reading the MAC address
Connects devices on a twisted-pair network
Switch- A switch forwards data to its destination by using the MAC address embedded in each packet
Connects devices on an Ethernet twisted-pair network
Hub- a hub does not perform any tasks besides signal regeneration
Translates from one data format into another
Gateway- can be hardware or software based. Any device that translates data formats is called a gateway
Translates digital signals used on a LAN into those used on a WAN
Channel Service Unit/Data Service Unit (CSU/DSU)- Sometims incorporated into other devices, such as a router with WANT connection
Provides serial communication capabilities across phone lines
Modem- Modems modulate the digital signals into analog at the sending end and perform the reverse function at the receiving end
Enables systems to connect to the network
Network Card- interfaces can be add-in expansion cards, express cards, or built-in interfaces
Interconnects older technology with new
Media converter- is a hardware device that connects newer Gigabit Ethernet technologies with older 100BaseT networks or older copper standards with fiber
Provides controlled data access between networks
Firewalls- can be hardward or software based. They are an essential part of a network’s security strategy
Automatically distributes IP information
Dynamic Host Configuration Protocol (DHCP) assigns all IP information, including IP address, subnet mask, DNS, gateway, and more
Functions as a switch or router
Multilayer switch- Operates on layers 2 and 3 of the OSI model as a switch and can perform router functionality
Forwards data by application
Content Switch- Can identify and forward data by its port and application
Distributes network load
Load balancer- increases redundancy by distributing the load to multiple servers
Combines network services
Multifunction devices- these are hardware devices that combine multiple network services into a single device, reducing cost and easing admin difficulty
Provides name resolution from hostnames to IP addresses
DNS Server- answers requests to translate hostnames into IP addresses
Manages network Bandwitdth
Bandwidth shaper- monitors and controls bandwidth usage
Manages client internet requests
Proxy Server- Serves two key network performances: increases network performance by caching, and filters outgoing client requests.
- Several users on your network are downloading from peer-to-peer networks,
tying up bandwidth during peak hours. Which of the following is used to manage
network bandwidth?
❍ A. Load leveler
❍ B. Load toner
❍ C. Bandwidth toner
❍ D. Bandwidth shaper
- D. The term bandwidth shaping describes the mechanisms used to control
bandwidth usage on the network. With this, administrators have complete control
over who uses bandwidth, for what purpose, and the time of day bandwidth
can be used. Bandwidth shaping establishes priorities for data traveling to and
from the Internet and within the network.
2. Which of the following devices passes data based on the MAC address? ❍ A. Hub ❍ B. Switch ❍ C. MSAU ❍ D. Router
- B. When determining the destination for a data packet, the switch learns the
MAC address of all devices attached to it and then matches the destination
MAC address in the data it receives. None of the other devices listed passes
data based solely on the MAC address.
- On a virtual desktop what is the term that encompasses the software and
hardware needed to create the virtual environment?
- The virtual desktop is often called a virtual desktop interface (VDI) and
that term encompasses the software and hardware needed to create the
virtual environment.
- True or False: NaaS is similar to the Software as a Service (SaaS) cloud
computing model in that it is provided on demand in a pay-as-you-go
model.
- True. NaaS is similar to the Software as a Service (SaaS) cloud computing
model in that it is provided on demand in a pay-as-you-go model.
The virtual desktop is often called a ___ ___ and
that term encompasses the software and hardware needed to create the virtual
environment.
virtual desktop interface (VDI)
1. Which of the following is an open source virtual switch? ❍ A. VirtualBox ❍ B. VMware ❍ C. Xen ❍ D. Open vSwitch
- D. Open vSwitch is an open source virtual switch licensed beneath the Apache
2.0 license. It can be found at http://openvswitch.org. The other options listed
(some proprietary and some open source) are for virtual desktops.
- When a vendor offers to provide all networking for a client—freeing the company
from needing to worry about bandwidth, connectivity, scalability, and all the
issues normally associated with networking—what is it known as?
❍ A. SaaS
❍ B. NaaS
❍ C. SAN
❍ D. NAS
- B. Known as Network as a Service (Naas), this alleviates the company’s concerns
about bandwidth, connectivity, scalability, and all the issues normally
associated with networking.
- What is the point of demarcation with a small office?
- The point of demarcation is always the point where the service provider
stops being responsible for the wiring and it becomes your responsibility.
- True or False: Cable modems and DSL modems are commonly used in
SOHO implementations for Internet access.
- True. Cable modems and DSL modems are commonly used in SOHO
implementations for Internet access.
1. On a typical cable modem, which panel light is found beneath the power light? ❍ A. Receive ❍ B. Send ❍ C. Online ❍ D. Activity
- A. A typical sequence of lights on a cable modem is power, receive, send,
online, and activity.
- Which of the following is true of many SOHO routers?
❍ A. They close down the DHCP ports by default.
❍ B. They close down the NAT ports by default.
❍ C. They close down the ICMP ports by default.
❍ D. They leave open the DHCP, NAT, and ICMP ports by default.
- C. Many SOHO routers close down the ICMP ports by default.
- What are T-lines used for, and what is the maximum speed of T1 and T3?
- T-carrier lines create point-to-point network connections for private networks.
T1 lines offer transmission speeds of up to 1.544Mbps, whereas
T3 lines offer transmission speeds of 44.736Mbps.
- What are the X.25 transmission speed restrictions?
- X.25 is restricted to transmission rates of 56Kbps or 64Kbps with digital
implementations.
- What is the difference between circuit switching and packet switching?
- Circuit switching offers a dedicated transmission channel that is reserved
until it is disconnected. Packet switching enables packets to be routed
around network congestion.
In ___ ___, messages are broken into smaller pieces called packets.
Each packet is assigned source, destination, and intermediate node addresses.
Packets are required to have this information because they do not always use
the same path or route to get to their intended destination.
packet switching
Two types of packet-switching methods are used on networks are:
Virtual-circuit packet switching: and Datagram packet switching:
WIth ___ ___ ____, a logical connection is established
between the source and the destination device. This logical connection
is established when the sending device initiates a conversation with the
receiving device. The logical communication path between the two
devices can remain active for as long as the two devices are available or
can be used to send packets once. After the sending process has completed,
the line can be closed.
Virtual-circuit packet switching
Unlike virtual-circuit packet switching, ___ ___ ___ does not establish a logical connection between the sending and transmitting devices. The packets in this type are independently sent, meaning that they can take different
paths through the network to reach their intended destination. To do this, each packet must be individually addressed to determine its source and destination. This method ensures that packets take the easiest possible routes to their destination and avoid high-traffic areas. These are mainly used on the Internet.
Datagram packet switching:
In contrast to the packet-switching method, ___ ____ requires a dedicated physical connection between the sending and receiving devices. The most commonly used analogy to represent this is a telephone
conversation in which the parties involved have a dedicated link between them for the duration of the conversation. When either party disconnects, the circuit
is broken, and the data path is lost.
circuit switching
The two types of ISDN are:
Basic Rate Interface (BRI) and
Primary Rate Interface (PRI).
____ ISDN uses three separate channels; two bearer (B) channels of 64Kbps
each and a delta channel of 16Kbps. B channels can be divided into four D
channels, which ENABLE businesses to have eight simultaneous Internet
connections. The B channels carry the voice or data, and the D channels are
used for signaling.
BRI- BRI ISDN channels can be used separately using 64Kbps transfer or combined to
provide 128Kbps transfer rates.
____ is a form of ISDN that generally is carried over a T1 line and can provide transmission rates of up to 1.544Mbps. ___ is composed of 23 B channels, each providing 64Kbps for data/voice capacity, and one 64kbps D channel,
which is used for signaling.
PRI
EXAM ALERT: ISDN is considered a leased line because access to ISDN is leased from a service
provider.
EXAM ALERT
BRI to PRI ISDN Comparison
Characteristic BRI PRI
Speed 128Kbps 1.544Mbps
Channels 2B+D 23B+D
Transmission carrier ISDN T1
BRI to PRI ISDN Comparison
Characteristic BRI PRI
Speed 128Kbps 1.544Mbps
Channels 2B+D 23B+D
Transmission carrier ISDN T1
___ ___ are high-speed dedicated digital lines that can be leased from telephone companies. This creates an always-open, always-available line
between you and whomever you choose to connect to when you establish the service. ___ ___ lines can support both voice and data transmissions and are often used to create point-to-point private networks.
T-carrier lines
Four types of T-carrier lines are available. They are:
T1, T2, T3, T4
T- carrier line that Offers transmission speeds of 1.544Mbps and can create point-to-point dedicated digital communication paths. these lines have commonly
been used for connecting LANs. In North America, DS (digital signal) notation is used with T-lines to describe the circuit. For all practical purposes, DS1 is synonymous with it.
T1
T-carrier line which Offers transmission speeds of 6.312Mbps. They accomplish this by
using 96 64Kbps B channels.
T2
This T-carrier line Offers transmission speeds of up to 44.736Mbps, using 672 64Kbps B channels. Digital signal 3 (DS3) is a more accurate name in North America, but ___ is what most refer to the link as.
T3 (When you take the exam, think of DS3 and T3 as synonymous.)
This T-carrier line Offers impressive transmission speeds of up to 274.176Mbps by
using 4,032 64Kbps B channels.
T4
What is the speed for T1 and T3 lines
T1- 1.544Mbps/ T3- 44.736Mbps
OCx Level Transmission Rate for
OC-1 51.84Mbps
51.84Mbps
OCx Level Transmission Rate for
OC-3
155.52Mbps
OCx Level Transmission Rate for
OC-12
622.08Mbps
OCx Level Transmission Rate for
OC-24
1.244Gbps
OCx Level Transmission Rate for
OC-48
2.488Gbps
OCx Level Transmission Rate for
OC-96
4.976Gbps
OCx Level Transmission Rate for
OC-192
9.953Gbps
OCx Level Transmission Rate for
OC-768
39.813Gbps
ExamAlert
When you take the exam, equate SDH with SONET.
Synchronous Optical Network (SONET), Synchronous Digital Hierarchy (SDH) is the European counterpart to SONET
a ___ ___ is one in which unpowered optical splitters
are used to split the fiber so it can service a number of different locations and
brings the fiber either to the curb, the building, or the home.
passive optical network (PON)
____ was one of the original packet-switching technologies, but today it has
been replaced in many applications by Frame Relay
X.25
___ ___is a WAN protocol that operates at the physical and data link layers of the OSI model. ___ ___ enables data transmission for intermittent
traffic between LANs and between endpoints in a WAN.
Frame Relay
In the Frame Relay world, the term
___ refers to terminating equipment located within a company’s network. Termination equipment includes such hardware as end-user systems, servers, routers, bridges, and switches.
DTE- Data terminal equipment
In frame relay, ___ refers to the
equipment owned by the carrier. This equipment provides the switching
services for the network and therefore is responsible for actually transmitting
the data through the WAN.
DCE-Data circuit-terminating equipment
In Frame Relay, ____Represents a temporary virtual circuit established and maintained only for the duration of a data transfer session.
Switched virtual circuit (SVC):
A permanent dedicated virtual link shared in a Frame Relay network, replacing a hard-wired dedicated endto-
end line.
Permanent virtual circuit (PVC):
___ is a packet-switching technology that provides transfer speeds ranging from 1.544Mbps to 622Mbps. It is well suited for a variety of data types, such as voice, data, and video. Using fixed-length packets, or cells, that are 53 bytes long, ___ can operate more efficiently than variable-length-packet packetswitching technologies such as Frame Relay.
Asynchronous Transfer Mode (ATM)
Your company currently uses a standard PSTN communication link to transfer
files between LANs. Until now, the transfer speeds have been sufficient for the
amount of data that needs to be transferred. Recently, a new application was
purchased that requires a minimum transmission speed of 1.5Mbps. You have
been given the task to find the most cost-effective solution to accommodate the
new application. Which of the following technologies would you use?
❍ A. T3
❍ B. X.25
❍ C. T1
❍ D. BRI ISDN
- C. A T1 line has a transmission capability of 1.544Mbps and is considerably
cheaper than a T3 line. X.25 and BRI ISDN cannot provide the required transmission
speed.
- Which of the following best describes the process to create a dedicated circuit between
two communication endpoints and direct traffic between those two points?
❍ A. Multiplexing
❍ B. Directional addressing
❍ C. Addressing
❍ D. Circuit switching
- D. Circuit switching is the process of creating a dedicated circuit between two
communications endpoints and directing traffic between those two points. None
of the other answers are valid types of switching.
- Which of the following statements are true of ISDN? (Choose the two best
answers.)
❍ A. BRI ISDN uses two B+1 D channels.
❍ B. BRI ISDN uses 23 B+1 D channels.
❍ C. PRI ISDN uses two B+1 D channels.
❍ D. PRI ISDN uses 23 B+1 D channels.
- A, D. BRI ISDN uses two B+1 D channels, which are two 64Kbps data channels,
and PRI ISDN uses 23 B+1 D channels. The D channel is 16Kbps for BRI and
64Kbps for PRI.
- You have been hired to establish a WAN connection between two offices: one in
Vancouver and one in Seattle. The transmission speed can be no less than
2Mbps. Which of the following technologies could you choose?
❍ A. T1
❍ B. PSTN
❍ C. T3
❍ D. ISDN
- C. The only possible answer capable of transfer speeds above 2Mbps is a T3
line. None of the other technologies listed can provide the transmission speed
required.
- On an ISDN connection, what is the purpose of the D channel?
❍ A. It carries the data signals.
❍ B. It carries signaling information.
❍ C. It enables multiple channels to be combined to provide greater bandwidth.
❍ D. It provides a temporary overflow capacity for the other channels.
- B. The D channel on an ISDN link carries signaling information, whereas the B,
or bearer, channels carry the data.
6. Which of the following circuit-switching strategies does ATM use? (Choose the two best answers.) ❍ A. SVC ❍ B. VCD ❍ C. PVC ❍ D. PCV
- A, C. ATM uses two types of circuit switching: PVC and SVC. VCD and PCV are
not the names of switching methods.
- Due to recent cutbacks, your boss approaches you, demanding an alternative to
the company’s costly dedicated T1 line. Only small amounts of data require
transfer over the line. Which of the following are you likely to recommend?
❍ A. ISDN
❍ B. FDDI
❍ C. The PSTN
❍ D. X.25
- C. When little traffic will be sent over a line, the PSTN is the most cost-effective
solution; although, it is limited to 56Kbps. All the other WAN connectivity methods
accommodate large amounts of data and are expensive compared to the
PSTN.
8. Which of the following technologies requires a logical connection between the sending and receiving devices? ❍ A. Circuit switching ❍ B. Virtual-circuit packet switching ❍ C. Message switching ❍ D. High-density circuit switching
- B. When virtual-circuit switching is used, a logical connection is established
between the source and the destination device.
- What is VHDSL commonly used for?
- VHDSL supports high-bandwidth applications such as VoIP and HDTV.
- True or False: DSL using regular phone lines transfers data over the same
copper wire.
- True. DSL using regular phone lines transfers data over the same copper
wire.
- What is the difference between a one-way and a two-way satellite
system?
- A one-way satellite system requires a satellite card and a satellite dish
installed at the end user’s site. This system works by sending outgoing
requests on one link using a phone line, with inbound traffic returning on
the satellite link. A two-way satellite system, on the other hand, provides
data paths for both upstream and downstream data.
The term _____ often refers to high-speed Internet access. Both DSL and cable modem are common ____ Internet technologies. ____ routers and ____ modems are network devices that support both DSL and cable.
broadband
_____ is an Internet access method that uses a standard phone line to provide high-speed Internet access. It is most commonly associated with highspeed Internet access; because it is a relatively inexpensive Internet access, it is often found in homes and small businesses. With this type, a different frequency can be used for digital and analog signals, which means that you can talk on the phone while you upload data.
DSL
For DSL services, two types of systems exist. They are:
Asymmetric Digital Subscriber
Line (ADSL) and High-Rate Digital Subscriber Line (HDSL).
___ provides a high data rate in only one direction. It enables fast download speeds
but significantly slower upload speeds. It is designed to work with existing analog telephone service (POTS) service. With fast download speeds, it is well suited for home-use Internet access where uploading large amounts of data isn’t a frequent task.
Asymmetric Digital Subscriber
Line (ADSL)
___ provides a bidirectional high data rate service
that can accommodate services, such as videoconferencing, that require high data rates in both directions.
High-Rate Digital Subscriber Line (HDSL)
A variant of HDSL is ____which provides an HDSL service at very high data transfer rates.
VHDSL (Very High-Rate Digital Subscriber Line),
The ___, often considered a POTS, is the entire collection of interconnected telephone wires throughout the world. Discussions of the ___ include all the equipment that goes into connecting two points, such as the cable, the networking equipment, and the telephone exchanges.
The Public Switched Telephone Network
PSTN
EXAM ALERT:
If money is a major concern, the PSTN is the method of choice for creating a WAN.
If money is a major concern, the PSTN is the method of choice for creating a WAN.
- Which of the following technologies require dialup access? (Choose the two best
answers.)
❍ A. FDDI
❍ B. ISDN
❍ C. Packet switching
❍ D. The PSTN
- B and D. Both the PSTN and ISDN require dialup connections to establish communication
sessions.
- Which of the following is an advantage of ISDN over the PSTN?
❍ A. ISDN is more reliable.
❍ B. ISDN is cheaper.
❍ C. ISDN is faster.
❍ D. ISDN uses 53Kbps fixed-length packets.
- C. One clear advantage that ISDN has over the PSTN is its speed. ISDN can
combine 64Kbps channels for faster transmission speeds than the PSTN can
provide. ISDN is no more or less reliable than the PSTN. ISDN is more expensive
than the PSTN. Answer D describes ATM.
3. Which of the following technologies is known as a 3G transitional technology that supports legacy architecture? ❍ A. HSPA+ ❍ B. LTE ❍ C. WiMax ❍ D. PON
- A. HSPA+ (Evolved High Speed Packet Access) is known as a 3G transitional
technology that supports legacy architecture.
4. What is the theoretical download speed possible with WiMax? ❍ A. 84Mbit/s ❍ B. 100Mbit/s ❍ C. 1Gbit/s ❍ D. 10Gbit/s
- C. The theoretical download speed possible with WiMax is 1Gbit/s. The speed
possible with HSPA+ is 84Mbits/s, whereas that possible with LTE is 100Mbit/s.
5. Which of the following is the time lapse between sending or requesting information and the time it takes to return? ❍ A. Echo ❍ B. Attenuation ❍ C. Bandwidth ❍ D. Latency
- D. Latency refers to the time lapse between sending or requesting information
and the time it takes to return.
6. Which of the following provides public hotspots for wireless Internet access? ❍ A. WISP ❍ B. WASP ❍ C. WSP+ ❍ D. WPST
- A. Wireless Internet access is provided by a Wireless Internet Service Provider
(WISP). The WISP provides public wireless Internet access known as hotspots.
Hotspots offer Internet access for mobile network devices such as laptops,
handheld computers, and cell phones in airports, coffee shops, conference
rooms, and so on.
7. What is the speed usually offered with dialup service? ❍ A. 1Gbps ❍ B. 256Kbps ❍ C. 144Kbps ❍ D. 56Kbps
- D. Almost without exception, ISPs offer 56Kbps access, the maximum possible
under current standards.
- What is the difference between RJ-11 and RJ-45 connectors?
- RJ-11 connectors are used with standard phone lines and are similar in
appearance to RJ-45 connectors used in networking. However, RJ-11
connectors are smaller. RJ-45 connectors are used with UTP cabling.
- What are the two most common connectors used with fiber-optic cabling?
- Fiber-optic cabling uses a variety of connectors, but SC and ST are more
commonly used than others. ST connectors offer a twist-type attachment,
whereas SCs have a push-on connector. LC and MT-RJ are other types of
fiber-optic connectors.
- What are F-type connectors used for?
- F-type connectors are used to connect coaxial cable to devices such as
Internet modems.
- What hardware is located at the demarcation point?
- The hardware at the demarcation point is the smart jack, also known as
the Network Interface Device (NID).
- What is BPL?
- Broadband over Power Lines (BPL) enables electrical wiring to be used to
build a network.
_____ transmissions use digital signaling over a single wire. Communication on ______ transmissions is bidirectional,
allowing signals to be sent and received, but not at the same time.
To send multiple signals on a single cable, _____ uses something
called Time Division Multiplexing (TDM). TDM divides a single channel into time slots. The key thing about TDM is that it doesn’t change how ______ transmission works—only how data is placed on the cable.
Baseband
In terms of LAN network standards, _____ transmissions use analog transmissions. For ______ transmissions to be sent and received, the medium must be split into two channels. (Alternatively, two cables can be used: one to send and one to receive transmissions.) Multiple channels are created using Frequency Division Multiplexing (FDM). FDM allows ___ media to accommodate traffic going in different directions on a single medium at the same time.
broadband
______mode enables one-way communication of data through the network,
with the full bandwidth of the cable used for the transmitting signal.
Simplex mode
accommodates transmitting
and receiving on the network, but not at the same time. Many networks
are configured for half-duplex communication.
half-duplex mode,
___can
simultaneously transmit and receive. This means that 100Mbps network
cards theoretically can transmit at 200Mbps
full-duplex
mode
is a problem when cables are installed near electrical devices, such as air
conditioners or fluorescent light fixtures. If a network medium is placed close
enough to such a device, the signal within the cable might become corrupt.
electromagnetic interference (EMI)
____refers to how the data signals
on two separate media interfere with each other. The result is that the
signal on both cables can become corrupt.
Crosstalk
____refers to the weakening of data signals as they travel through a
medium.
Attenuation
Data-grade cable that can transmit data up to 10Mbps with
a possible bandwidth of 16MHz.
Category 3:
Data-grade cable that has potential data throughput of
16Mbps.
Category 4:Category 4 cable is no longer used.
Data-grade cable that typically was used with Fast Ethernet
operating at 100Mbps with a transmission range of 100 meters
Category 5:Although Category 5 was a popular media type, this cable is an outdated
standard
Data-grade cable used on networks that run at
10/100Mbps and even up to 1000Mbps, can be used up to 100 meters, provides a minimum of 100MHz of bandwidth
Category 5e:
High-performance UTP cable that can transmit data up to
10Gbps. has a minimum of 250MHz of bandwidth and specifies
cable lengths up to 100 meters with 10/100/1000Mbps transfer,
along with 10Gbps over shorter distances.
Category 6:
Offers improvements by offering a minimum of 500MHz of bandwidth.
Category 6a:
Coax Cable Used to generate low-power video connections. cannot be used over long distances because of its high-frequency
power losses.
RG-59 /U
Coax cable that Has a solid copper core. Used for radio communication and thin
Ethernet (10Base2).
RG-58 /U
Coax cable that Has a stranded wire core. Used for radio communication and thin
Ethernet (10Base2).
RG-58 A/U
Coax cable Used for military specifications.
RG-58 C/U
Coax cable Often used for cable TV and cable modems.
RG-6
Ttypes of fiber optic cable where Many beams of light travel through the cable, bouncing
off the cable walls. This strategy actually weakens the signal, reducing
the length and speed at which the data signal can travel.
Multimode Fiber
Type of fiber optic cable that Uses a single direct beam of light, thus allowing for
greater distances and increased transfer speeds.
Single-mode FIber
EXAM ALERT! Cables run through the plenum must have two important characteristics: They must
be fire-resistant, and they must not produce toxic fumes if exposed to intense heat.
EXAM ALERT
___ connectors are associated with coaxial media and 10Base2 networks
BNC Connectors
_____ connectors are small plastic connectors used on telephone
cables. They have capacity for six small pins. However, in many cases,
not all the pins are used.
RJ- (registered jack) 11
____ connectors are used with twistedpair
cabling, the most prevalent network cable in use today. they support up to eight
wires.
RJ-45
_____ are screw-on connections used to
attach coaxial cable to devices. This includes RG-59 and RG-6 cables.most commonly associated
with connecting Internet modems to cable or satellite Internet service
providers’ (ISPs’) equipment. also used to
connect to some proprietary peripherals. They have a “nut” on the connection that provides something to
grip as the connection is tightened by hand. If necessary, this nut can also be
lightly gripped with pliers to aid disconnection.
F- Type Connectors
Fiber connector that uses a half-twist
bayonet type of
lock.
ST Connector
Fiber connector that uses a push-pull connector similar to common audio and video plugs and sockets
SC Connector
\_\_\_\_ Fiber connectors have a flange on top, similar to an RJ-45 connector, that aids secure connection.
LC
___ fiber connector is a popular
connector for two
fibers in a very
small form factor.
MT-RJ
_____is a TIA/EIA standard for serial transmission
between computers and peripheral devices such as modems, mice, and keyboards. was introduced way back in the 1960s and is
still used today. However, peripheral devices are more commonly connected
using USB or wireless connections.
RS-232 (Recommended Standard 232)
_____ ports are now an extremely common sight on both
desktop and laptop computer systems. Like IEEE 1394, it is associated more with connecting consumer peripherals such as MP3 players and digital cameras than with networking. However, many manufacturers now make wireless network cards that plug directly into a ____ port. Most desktop and
laptop computers have between two and four ____ ports, but ____ hubs are
available that provide additional ports if required.
Universal Serial Bus (USB)
When you have two dissimilar types of network media, a _____ is
used to allow them to connect. Depending upon the conversion being done,
it can be a small device barely larger than the connectors themselves,
or a large device within a sizable chassis.
media converter
EXAM ALERT: Make sure you know that the possibilities listed here exist. . Singlemode fiber to Ethernet . Singlemode to multimode fiber . Multimode fiber to Ethernet . Fiber to Coaxial
KNOW THESE
___ and ___ are telecommunications standards from TIA and EIA. These
standards specify the pin arrangements for the RJ-45 connectors on UTP
or STP cables. The number ____refers to the order in which the wires within
the Category 5 cable are terminated and attached to the connector.
568A and 568B
Specifically, in a crossover cable, wires _ and _ and wires _ and _ are crossed.
1 and 3 and 2 and 6
EXAM ALERT: The crossover cable can be used to directly network two PCs without using a hub
or switch. This is done because the cable performs the function of the switch.
EXAM ALERT
The ___ cable is a Cisco proprietary cable used to connect a computer system to a router or switch console port. It resembles an Ethernet UTP cable; however, it is not possible to use it on anything but
Cisco equipment.
rollover
EXAM ALERT: Remember that the rollover cable is a proprietary cable used to connect a PC to a
Cisco router.
EXAM ALERT
A ___ cable, also known as a plug, is used to test and isolate network problems. If made correctly, the it plug causes the link light on a device such as a network interface card (NIC) to come on.
loopback
EXAM ALERT: Know a loopback cable is a basic troubleshooting tool.
EXAM ALERT
in Network Cross-Connects, this section Connects client systems to the network
Horizontal cabling:
in Network Cross-Connects this Runs between floors to connect different
locations on the network.
Vertical (backbone) cabling:
in cable distribution: The location where outside cables
enter the building for distribution. This can include Internet and phone
cabling.
Vertical or main cross-connect:
in cable distribution: The location where the vertical and horizontal
connections meet.
Horizontal cross-connect:
in cable distribution:
Intermediate cross-connect: Typically used in larger networks.
Provides an intermediate cross-connect between the main and horizontal
cross-connects.
The term ___ ___refers to the point where the cables running throughout
the network meet and are connected.
cross-connect
A ___ ___ is a
freestanding or wall-mounted unit with a number of RJ-45 port connections
on the front. In a way, it looks like a wall-mounted hub without the light-emitting
diodes (LEDs). provides a connection point
between network equipment such as hubs and switches and the ports to which
PCs are connected, which normally are distributed throughout a building.
patch panel
Two main types of punchdown blocks are
type 66 and type 110
Type ___ is an older design punchdown block used to connect wiring for telephone systems and other low-speed network systems
66
Type ___ punchdown block is used to connect network cable. can also be used at the other end of the network
cable at the RJ-45 wall jack
to patch panels
110
The main wiring closet for a network typically holds the majority of the network gear, including routers, switches, wiring, servers, and more. This is also typically the wiring closet where outside lines run into the network. This main wiring closet is known as the ___. One of the key components in the ___ is a primary patch panel. The network connector jacks attached to this patch panel lead out to the building for network connections.
Main Distribution Frame (MDF)
In some networks, multiple wiring closets are used. When this is the case, connection to a secondary wiring closets, or IDFs using a backbone cable is used
Intermediate Distribution Frame
IDF
As you might imagine, you need some form of hardware at the demarcation point. This is the smart jack, also known as the ___ ___ ___. The smart jack performs several primary functions:
Network Interface Device (NID)
Network Interface Device Function:
The___ is built into the smart jack.
Like the Ethernet loopback cable, it is used for testing purposes. In this case, the loopback feature enables remote testing so that technicians
do not always need to be called to visit the local network to isolate
problems.
loopback feature
Network Interface Device Function: The smart jack can amplify signals. This feature is similar to that of the function of repeaters in an Ethernet network.
Signal amplification:
Network Interface Device Function:
Lighting and other environmental conditions can
cause electrical surges that can quickly damage equipment. Many smart
jacks include protection from environmental situations.
surge protection
Network Interface Device Function:
Smart jacks typically include an this that allows the owner to identify if something goes wrong with the smart jack and therefore the connections at the demarcation point.
Remote Alarms
acts as a translator
between the LAN data format and the WAN data format.
Channel Service Unit/Data Service Unit (CSU/DSU)
EXAM ALERT:
Traditionally, the CSU/DSU has been in a box separate from other networking
equipment. However, the increasing use of WAN links means that some router
manufacturers are now including CSU/DSU functionality in routers or are providing
the expansion capability to do so.
EXAM ALERT
1. Which of following connectors is commonly used with fiber cabling? ❍ A. RJ-45 ❍ B. BNC ❍ C. SC ❍ D. RJ-11
- C. SC connectors are used with fiber-optic cable. RJ-45 connectors are used
with UTP cable, BNC is used for thin coax cable, and RJ-11 is used for regular
phone connectors.
2. Which of the following describes the loss of signal strength as a signal travels through a particular medium? ❍ A. Attenuation ❍ B. Crosstalk ❍ C. EMI ❍ D. Chatter
- A. The term used to describe the loss of signal strength for media is attenuation.
Crosstalk refers to the interference between two cables, EMI is electromagnetic
interference, and chatter is not a valid media interference concern.
3. What kind of cable would you associate with an F-type connector? ❍ A. Fiber-optic ❍ B. UTP ❍ C. Coaxial ❍ D. STP
- C. F-type connectors are used with coaxial cables. They are not used with fiberoptic,
Unshielded Twisted Pair (UTP), or Shielded Twisted Pair (STP) cabling.
- A user calls to report that he is experiencing periodic problems connecting to the
network. Upon investigation, you find that the cable connecting the user’s PC to
the switch is close to a fluorescent light fitting. What condition is most likely
causing the problem?
❍ A. Crosstalk
❍ B. EMI
❍ C. Attenuation
❍ D. Faulty cable
- B. EMI is a type of interference that is often seen when cables run too close to
electrical devices. Crosstalk is when two cables interfere with each other.
Attenuation is a loss of signal strength. Answer D is incorrect also. It may be that
a faulty cable is causing the problem. However, the question asked for the most
likely cause. Because the cable is running near fluorescent lights, the problem is
more likely associated with EMI.
5. Which of the following is not a type of fiber-optic connector used in network implementations? ❍ A. MT-RJ ❍ B. SC ❍ C. BNC ❍ D. LC
- C. BNC is a connector type used with coaxial cabling. It is not used as a connector
for fiber-optic cabling. MT-RJ, SC, and LC are all recognized types of
fiber-optic connectors.
6. Which of the following fiber connectors uses a twist-type connection method? ❍ A. ST ❍ B. SC ❍ C. BNC ❍ D. SA
- A. ST fiber connectors use a twist-type connection method. SC connectors
use a push-type connection method. The other choices are not valid fiber
connectors.
7. Which Broadband over Power Lines standard exists for high-speed communication devices? ❍ A. MLME ❍ B. IEEE 754 ❍ C. IEEE 1901 ❍ D. Wibree
- C. The IEEE 1901 standard applies to high-speed communication devices and
Broadband over Power Lines (BPL). The other choices are not valid for
Broadband over Power Lines.
8. In a crossover cable, which wire is wire 1 crossed with? ❍ A. 2 ❍ B. 3 ❍ C. 4 ❍ D. 5
- B. In a crossover cable, wires 1 and 3 and wires 2 and 6 are crossed.
9. What are the two main types of punchdown blocks? (Choose two.) ❍ A. 110 ❍ B. 220 ❍ C. 66 ❍ D. 12
- A,C. The two main types of punchdown blocks are type 66 and type 110. Type
66 is an older design used to connect wiring for telephone systems and other
low-speed network systems and is not as widely used as type 110.
10. What device acts as a translator between the LAN data format and the WAN data format? ❍ A. CSMA/CD ❍ B. T568B ❍ C. MTRJ ❍ D. CSU/DSU
- D. A Channel Service Unit/Data Service Unit (CSU/DSU) acts as a translator
between the LAN data format and the WAN data format. Such a conversion is
necessary because the technologies used on WAN links are different from those
used on LANs.
- What are the characteristics/limitations of 1000BaseCX?
- 1000BaseCX offers 1000Mbps transfer speeds over shielded copper
cable. Distances are restricted to 25 meters.
- Which IEEE standard defines 10Gbps networks?
- 10Gbps networks are defined by the IEEE 802.3ae standard.
- What type of connectors can be used with 100BaseTX networks?
- 100BaseTX networks use RJ-45 connectors.
IEEE 802 Networking Standards: Standards for Interoperable LAN/MAN Security (SILS) (network
security)
802.10
IEEE 802 Networking Standards: Wireless networks
802.11
IEEE 802 Networking Standards: 100Mbps technologies, including 100BaseVG-AnyLAN
802.12
IEEE 802 Networking Standards:
Internetworking
802.1
IEEE 802 Networking Standards: The LLC (Logical Link Control) sublayer. called Logical Link Control (LLC), manages data flow
control and error control for the other IEEE LAN standards
802.2
IEEE 802 Networking Standards: CSMA/CD (Carrier Sense Multiple Access with Collision Detection) for Ethernet networks. define a range of networking systems based on the
original Ethernet standard.
802.3
IEEE 802 Networking Standards: A token-passing bus
802.4
IEEE 802 Networking Standards: Token ring networks
802.5
IEEE 802 Networking Standards: Metropolitan area network (MAN)
802.6
IEEE 802 Networking Standards: Broadband Technical Advisory Group
802.7
IEEE 802 Networking Standards: Fiber-Optic Technical Advisory Group
802.8
IEEE 802 Networking Standards: Integrated voice and data networks
802.9
EXAM ALERT: A node is any device connected to the network. A node might be a client computer, server computer, printer, router, or gateway
EXAM ALERT
Know that collisions do occur with CSMA. You can detect them (CD) or attempt to avoid them (CA).
ExamAlert
CSMA/CD is known as a contention media access method because systems contend
for access to the media.
ExamAlert
Know that CSMA/CA uses broadcasts.
ExamAlert
IEEE 802.3x Standard Characteristics:
___, also known as ____ enables you to use multiple channels at the same time to increase performance.
Bonding, also known as channel bonding,
IEEE 802.3x Standard Characteristics:
The term ___, which is the plural of ___, generically describes the methods by which data is transported from one point
to another. Common network ____ types include twisted-pair cable, coaxial
cable, infrared, radio frequency, and fiber-optic cable.
media, medium, media
Summary of ___ Characteristics:
Transmission method -Baseband Speed -10Mbps Total distance/segment- 100 meters Cable type Category- 3, 4, 5, or 6 UTP or STP Connector -RJ-45
10BaseT
Summary of 802.3u Fast Ethernet Characteristics
Transmission method-= Baseband Speed= 100Mbps Distance =100 meters Cable type= Category UTP, STP Connector type= RJ-45 Which one is this?
100BaseTX
Summary of 802.3u Fast Ethernet Characteristics
Transmission method-= Baseband
Speed= 100Mbps
Distance =412 meters (multimode half duplex);
10,000 meters (single mode full duplex)
Cable type= Fiber-optic
Connector type= SC, ST
Which one is this?
100BaseFX
Which IEEE 802.3z Gigabit Ethernet Characteristics has:
Transmission method= Baseband
Speed= 1000Mbps
Distance= Half Duplex 275 (62.5 micron myltimode fiber); half duplex 316 (50 micron multimode fiber; full duplex 275 (62.5 micron multimode fiber); full duplex 550 (50 micron multimode fiber)
Cable Type= 62.5/125 and 50/125 multimode fiber
Connector type= fiber connectors
1000BaseSX
Which IEEE 802.3z Gigabit Ethernet Characteristics has:
Transmission method= Baseband
Speed= 1000Mbps
Distance= Hapf duplex 316 (multimode and single mode fiber); full duplex 550(multimode fiber); full duplex 5000 (single mode fiber)
Cable Type= 62.5/125 and 50/125 multimode fiber; two 10 micron single mode iptical fibers
1000BaseLX
Which IEEE 802.3z Gigabit Ethernet Characteristics has:
Transmission method= Baseband
Speed= 1000Mbps
Distance= 25 meters for both full and half duplex operations
Cable Type= Shielded copper cable
Connector Type= Nine pin shielded connector
1000BaseCX
Summary of \_\_\_\_ Characteristics: Transmission method= Baseband Speed =1000Mbps Total distance/segment= 75 meters Cable type= Category 5 or better Connector type= RJ-45
1000BaseT
10 Gigabit Ethernet is defined in the IEEE 802.3ae standard.
EXAM ALERT
Summary of 802.3an Characteristics: Transmission method = Baseband Speed = 10 gigabit Total distance/segment = 100 meters Category 6a cable; 55 meters Category 6 cable Cable type = Category 6, 6a UTP or STP Connector = RJ-45
10GBaseT
- You troubleshoot a network using 1000BaseCX cable, and you suspect that the
maximum length has been exceeded. What is the maximum length of
1000BaseCX cable?
❍ A. 1,000 meters
❍ B. 100 meters
❍ C. 25 meters
❍ D. 10,000 meters
- C. The 1000BaseCX standard specifies Gigabit Ethernet transfer over Category 5
UTP cable. It uses STP twisted-pair cable and has a 25-meter length restriction.
2. Which of the following 10 Gigabit Ethernet standards has the greatest maximum transmission distance? ❍ A. 10GBaseSR ❍ B. 10GBaseER ❍ C. 10GBaseLR ❍ D. 10GBaseXR
- B. The 10GBaseER standard specifies a maximum transmission distance of
40,000 meters. The 10GBaseSR standard specifies a maximum transmission
distance of 300 meters, whereas 10GBaseLR specifies a maximum transmission
distance of 10,000 meters. 10GBaseXR is not a recognized 10 Gigabit Ethernet
standard.
- Your manager has asked you to specify a high-speed 10GbE link to provide connectivity
between two buildings 3km from each other. Which of the following
IEEE standards are you likely to recommend?
❍ A. 10GBaseLR
❍ B. 10GBaseSR
❍ C. 10GBaseT4
❍ D. 10GBaseFL
- A. 10GBaseLR can be used over distances up to 10km. 10GBaseSR can only be
used up to a maximum distance of 300 meters. 10GBaseT4 and 10GBaseFL are
not recognized 10-Gigabit Ethernet standards.
- In a 100BaseTX network environment, what is the maximum distance between
the device and the networking equipment, assuming that no repeaters are used?
❍ A. 1,000 meters
❍ B. 100 meters
❍ C. 500 meters
❍ D. 185 meters
- B. 100BaseT networks use UTP cabling, which has a maximum cable length of
100 meters. Answer A is incorrect because this distance could be achieved only
with UTP cabling by using repeaters. Answer C specifies the maximum cable
length for 10Base5 networks. Answer D specifies the maximum cable length for
10Base2 networks.
- What is the network name needed to connect to a wireless AP?
- SSID (Service Set Identifier).
- True or False: A wireless access point (AP) is both a transmitter and
receiver (transceiver) device used for wireless LAN (WLAN) radio signals.
- True. A wireless access point (AP) is both a transmitter and receiver
(transceiver) device used for wireless LAN (WLAN) radio signals.
An AP can operate as a bridge, connecting a standard wired network to wireless
devices, or as a router, passing data transmissions from one access point to
another.
EXAM ALERT
____ is a network name needed to connect to a wireless AP.
Service Set Identifier (SSID)
___ refers to a wireless network that uses a single
AP and one or more wireless clients connecting to the AP.
Basic Service Set (BSS)—
____Refers to two or more connected BSSs
that use multiple APs. The ESS is used to create WLANs or larger
wireless networks and is a collection of APs and clients
Extended Service Set (ESS)—
Although the terms
____ and SSID are used interchangeably, there is a difference between the two. SSID is the name used with BSS networks. ___ is the network name used with an ___ wireless network design. With an ___, not all APs necessarily use the same name.
Extended Service Set Identifier (ESSID)—
The MAC address of the Basic Service Set (BSS) AP. The ___ is not to be confused with the SSID, which is the name of the wireless network.
Basic Service Set Identifier (BSSID)—
When troubleshooting or designing wireless networks, the ___ is an important consideration. The ___ refers to the AP’s coverage area. The ___ for an AP depends on many factors, including the strength of the AP antenna, interference in the area, and whether an omnidirectional or directional antenna is used
Basic Service Area (BSA)
When troubleshooting a wireless problem in Windows, you can use the ipconfig
command to see the status of IP configuration. Similarly, the ifconfig command
can be used in Linux. In addition, Linux users can use the iwconfig command to
view the state of your wireless network. Using iwconfig, you can view such
important information as the link quality, AP MAC address, data rate, and encryption
keys, which can be helpful in ensuring that the parameters in the network are
consistent.
EXAM ALERT
____ refers to the theoretical maximum of a wireless standard, such as
100Mbps.
Data rate refers to the theoretical maximum of a wireless standard, such as
100Mbps.
___refers to the actual speeds achieved after all implementation
and interference factors.
Throughput
____ ___ ___ are an important part of the wireless network because
it is their job to advertise the presence of the access point so that systems can
locate it.
Beacon Management Frames
In ____ scanning: The client system listens for the beacon frames to
discover the AP. After it is detected, the beacon frame provides the
information necessary for the system to access the AP.
Passive
in ____ scanning: The client station transmits another type of management frame known as a probe request. The probe request goes out from the client system, looking for a specific SSID or any SSID within its area. After the probe request is sent, all APs in the area with the same SSID reply with another frame, the probe response. The information contained in the probe response is the same information included with the beacon frame. This information enables the client to access the system.
Active
______ spectrum refers to the manner in which data signals travel through a radio frequency. With ___ spectrum, data does not travel straight through a single RF band; this type of transmission is known as narrowband transmission. ____ spectrum, on the other hand, requires that data signals either alternate between carrier frequencies or constantly change their data pattern. Although the shortest distance between two points is a straight line (narrowband), ____ spectrum is designed to trade bandwidth efficiency for reliability, integrity, and security. ___-spectrum signal strategies use more bandwidth than in the case of narrowband transmission, but the trade-off is a data signal that is clearer and easier to detect.
Spread
The two types of spread-spectrum radio
are ____ ____ and ____ ____.
frequency hopping, direct sequence
_____requires the use of narrowband signals that change frequencies in a predictable pattern. The term refers to data signals hopping
between narrow channels.
frequency hopping
With _____ transmissions, the signal is spread over a full transmission frequency spectrum. For every bit of data sent, a redundant bit pattern is also sent. This 32-bit pattern is called a chip. These redundant bits of data provide both security and delivery assurance. The reason transmissions are so safe and reliable is simply because the system sends so many redundant copies of the data, and only a single copy is required to have complete transmission of the data or information. ____ can minimize the effects of interference and background
noise.
Direct-Sequence Spread-Spectrum (DSSS)
Technology
When a single AP is connected to the wired network and to a set of wireless stations,
it is called a Basic Service Set (BSS). An Extended Service Set (ESS)
describes the use of multiple BSSs that form a single subnetwork. Ad hoc mode is
sometimes called an Independent Basic Service Set (IBSS).
ExamAlert
The ______ process occurs when a wireless adapter is turned on. The client adapter immediately begins scanning the wireless frequencies for wireless APs or, if using ad hoc mode, other wireless devices. When the wireless client is configured to operate in infrastructure mode, the user can choose a
wireless AP with which to connect. This process may also be automatic, with the AP selection based on the SSID, signal strength, and frame error rate. Finally, the wireless adapter switches to the assigned channel of the selected wireless AP and negotiates the use of a port.
association
If at any point the signal between the devices drops below an acceptable level, or if the signal becomes unavailable for any reason, the wireless adapter initiates another scan, looking for an AP with stronger signals. When the new AP is located, the wireless adapter selects it and associates with it. This is known
as ______.
reassociation
The 802.11 standards enable a wireless client to roam between multiple APs. An AP transmits a beacon signal every so many milliseconds. It includes a time stamp for client synchronization and an indication of supported data rates. A client system uses the beacon message to identify the strength of the existing connection to an AP. If the connection is too weak, the roaming client attempts to associate itself with a new AP. This enables the client system to roam between distances and APs.
ExamAlert
1. Which of the following wireless protocols operate at 2.4GHz? (Select two.) ❍ A. 802.11a ❍ B. 802.11b ❍ C. 802.11g ❍ D. 802.11n
- B, C, and D. Wireless standards specify an RF range on which communications
are sent. The 802.11b and 802.11g standards use the 2.4GHz range. 802.11a
uses the 5GHz range. 802.11n can operate at 2.4GHz and 5GHz. For more information,
see the section “802.11 Wireless Standards.”
- Under what circumstance would you change the default channel on an access
point?
❍ A. When channel overlap occurs between access points
❍ B. To release and renew the SSID
❍ C. To increase WEP security settings
❍ D. To decrease WEP security settings
- A. Ordinarily, the default channel used with a wireless device is adequate; however,
you might need to change the channel if overlap occurs with another nearby
access point. The channel should be changed to another, nonoverlapping
channel. Changing the channel would not impact the WEP security settings. For
more information, see the section “Wireless Radio Channels.”
- A client on your network has had no problems accessing the wireless network in
the past, but recently she moved to a new office. Since the move she cannot
access the network. Which of the following is most likely the cause of the
problem?
❍ A. The SSIDs on the client and the AP are different.
❍ B. The SSID has been erased.
❍ C. The client has incorrect WEP settings.
❍ D. The client system has moved too far from the access point.
- D. An AP has a limited distance that it can send data transmissions. When a client
system moves out of range, it can’t access the AP. Many strategies exist to increase
transmission distances, including RF repeaters, amplifiers, and buying more powerful
antennas. The problem is not likely related to the SSID or WEP settings because
the client had access to the network before, and no settings were changed. For
more information, see the section “Wireless Troubleshooting Checklist.”
- What is the access method employed by the 802.11 wireless standards?
- All the 802.11 wireless standards employ the CSMA/CA access method.
- What technology can be considered the biggest development for 802.11n
and the key to the new speeds?
- Multiple input multiple output (MIMO) antenna technology is the biggest
development for 802.11n and the key to the new speeds.
____ uses multiplexing to increase the range
and speed of wireless networking. Multiplexing is a technique that combines
multiple signals for transmission over a single line or medium.
multiple input multiple output (MIMO)
- You are installing a wireless network solution, and you require a standard that
can operate using either 2.4GHz or 5GHz frequencies. Which of the following
standards would you choose?
❍ A. 802.11a
❍ B. 802.11b
❍ C. 802.11g
❍ D. 802.11n
- D. The IEEE standard 802.11n can use either the 2.4GHz or 5GHz radio frequencies.
802.11a uses 5GHz, and 802.11b and 802.11g use 2.4GHz. For more information,
see the section “802.11 Wireless Standards.”
- You are installing a wireless network solution that uses a feature known as
MIMO. Which wireless networking standard are you using?
❍ A. 802.11a
❍ B. 802.11b
❍ C. 802.11g
❍ D. 802.11n
- D. MIMO is used by the 802.11n standard and takes advantage of multiplexing
to increase the range and speed of wireless networking. Multiplexing is a technique
that combines multiple signals for transmission over a single line or medium.
MIMO enables the transmission of multiple data streams traveling on different
antennas in the same channel at the same time. A receiver reconstructs the
streams, which have multiple antennas. For more information, see the section
“The Magic Behind 802.11n.”
- What does WPA use to scramble encryption keys using a hashing
algorithm?
- WPA uses a temporal key integrity protocol (TKIP), which scrambles
encryption keys using a hashing algorithm.
- WPA2 uses CCMP. What is the strength of CCMP in terms of bits?
- CCMP uses 128-bit AES encryption with a 48-bit initialization vector.
Always equate WPA Enterprise with 802.1X: For exam purposes, the two are
synonymous.
ExamAlert
1. You are asked to configure the security settings for a new wireless network. You want the setting that offers the greatest level of security. Which of the following would you choose? ❍ A. WEP-Open ❍ B. WEP-Closed ❍ C. WEP-Shared ❍ D. WEP-Unshared 2.
- C. Both WEP-Open and WEP-Shared are forms of wireless security. WEP-Open
is the simpler of the two authentication methods because it does not perform
any type of client verification. It is a weak form of authentication because no
proof of identity is required. WEP-Shared requires that a WEP key be configured
on both the client system and the access point. This makes authentication with
WEP-Shared mandatory and therefore more secure for wireless transmission.
- Which of the following best describes 802.1X?
❍ A. A port-based access control
❍ B. A wireless standard specifying 11Mbps data transfer
❍ C. A wireless standard specifying 54Mbps data transfer
❍ D. An integrity-based access control
- A. 802.1X is an IEEE standard specifying port-based network access control.
Port-based network access control uses the physical characteristics of a
switched local area network (LAN) infrastructure to authenticate devices
attached to a LAN port and to prevent access to that port in cases where the
authentication process fails. For more information, see the section “WPA
Enterprise.”
- In the 802.1X security framework, which of the following best describes the role
of the supplicant?
❍ A. Authenticating usernames and passwords
❍ B. Encrypting usernames and passwords
❍ C. The system or node requesting access and authentication to a network
resource
❍ D. A control mechanism that allows or denies traffic that wants to pass
through a port
- C. The 802.1X security framework has three main components. The supplicant is
the system or node requesting access and authentication to a network resource.
The authenticator usually is a switch or AP that acts as a control mechanism,
allowing or denying traffic that wants to pass through a port. Finally, the authentication
server validates the credentials of the supplicant that is trying to access
the network or resource. For more information, see the section “WPA
Enterprise.”
- You have noticed that connections between nodes on one network are
inconsistent and suspect there may be another network using the same
channel. What should you try first?
- If connections are inconsistent, try changing the channel to another,
nonoverlapping channel.
- True or False: Weather conditions should not have a noticeable impact on
wireless signal integrity.
- False. Weather conditions can have a huge impact on wireless signal
integrity.
- You purchase a new wireless access point that uses no WEP security by default.
You change the security settings to use 128-bit encryption. How must the client
systems be configured?
❍ A. All client systems must be set to 128-bit encryption.
❍ B. The client system inherits security settings from the AP.
❍ C. WEP does not support 128-bit encryption.
❍ D. The client WEP settings must be set to autodetect.
- A. On a wireless connection between an access point and the client, each system
must be configured to use the same WEP security settings. In this case,
they must both be configured to use 128-bit encryption. For more information,
see the section “Wireless Troubleshooting Checklist.”
- You experience connectivity problems with your SOHO network. What can you
change in an attempt to solve this problem?
❍ A. Shorten the SSID.
❍ B. Remove all encryption.
❍ C. Lower the transfer rate.
❍ D. Raise the transfer rate.
- C. If you experience connectivity problems between wireless devices, try using
the lower transfer rate in a fixed mode to achieve a more stable connection. For
example, you can manually choose the wireless transfer rate. The higher the
transfer rate, the shorter the connection distance. For more information, see the
section “Wireless Troubleshooting Checklist.”
- Which network topology focuses on the direction in which data flows within
the physical environment?
- The logical network refers to the direction in which data flows on the network
within the physical topology. The logical diagram is not intended to focus on
- In computing, what are historical readings used as a measurement for
future calculations referred to as?
- Keeping and reviewing baselines is an essential part of the administrator’s role.
- True or False: Both logical and physical network diagrams provide an
overview of the network layout and function.
- True. Both logical and physical network diagrams provide an overview of
the network layout and function.
