Question | Answer |
are used to connect networks together and route packets of data from one
network to another | Routers |
the set of all devices on a network segment that hear all the broadcasts sent on
that segment | Broadcast Domain |
creates an internetwork and
provides connections to WAN services. | Router |
The router uses something called a ____interface
for WAN connections, specifically, a V.35 physical interface on a Cisco router | serial |
two advantages of using routers in your network | -They don’t forward broadcasts by default.
-They can filter the network based on layer 3 (Network layer) information (e.g., IP address). |
Four router functions | -Packet switching
-Packet filtering
-Internetwork communication
-Path selection |
This device forwards or filters frames | Switch |
This device uses logical addressing and provide what is called packet
switching | Router |
What is it called when routers
connect two or more networks together and use logical addressing (IP or IPv6)? | Internetwork |
routers use a ____ ______ (map of the internetwork) to make path
selections and to forward packets to remote networks | routing table |
create separate collision domains but a single broadcast domain | Switches |
when 1 device sends a packet on a network segment,forcing all other device on that same segment to pay attention to it. At the same time, a different
device tries to transmit, leading to a collision, after which both devices must retransmit, one
at a ti | Collision Domain |
provide a separate broadcast domain for each interface. | Routers |
You would use a ______ in a network to reduce collisions within broadcast
domains and to increase the number of collision domains in your network. | bridge |
create separate collision domains but a single broadcast domain | Switches |
provide a separate broadcast domain for each interface | Routers |
bridges/switches are used to segment networks, they will or will not isolate
broadcast or multicast packets? | will not |
even though you have
a switched network, you still need a _____ to provide your inter-VLAN communication, or
internetworking | router |
connections
between the switches are considered a _____ _______ | collision domain |
It divides the network communication process into smaller and simpler components, thus
aiding component development, design, and troubleshooting.
It allows multiple-vendor development through standardization of network components. | OSI Layered Model |
It encourages industry standardization by defining what functions occur at each layer of
the model.
It allows various types of network hardware and software to communicate. | OSI Layered Model |
It prevents changes in one layer from affecting other layers, so it does not hamper
development | OSI Layered Model |
it’s a set of guidelines that application
developers can use to create and implement applications that run on a network. It also provides
a framework for creating and implementing networking standards, devices, and internetworking
schemes. | OSI |
The
bottom four layers of the OSI define how____ is transmitted end to end | data |
In OSI, this layer • Keeps different applications data separate | Session |
In the OSI, this layer • Presents data
• Handles processing such as encryption | Presentation |
Which OSI layer
• Provides reliable or unreliable delivery
• Performs error correction before retransmit | Transport |
Which OSI layer Provides logical addressing,
• which routers use for path determination | Network |
Which OSI layer Combines packets into bytes and bytes into frames
• Provides access to media using MAC address
• Performs error detection not correction | Data Link |
Which OSI layer
• Moves bits between devices
• Specifies voltage, wire speed,
• and pin-out of cables | Physical |
The _____ layer is also responsible for identifying and establishing the availability of
the intended communication partner and determining whether sufficient resources for the
intended communication exist | Application |
The _______ layer is acting as an interface
between the actual application programs | Application |
Which OSI layer is this? It presents data to the Application layer
and is responsible for data translation and code formatting | presentation layer |
The ______ layer is responsible for setting up, managing, and then tearing down sessions
between Presentation layer entities. | Session |
This layer provides dialog control between
devices, or nodes. It coordinates communication between systems and serves to organize
their communication by offering three different modes: simplex, half duplex, and full
duplex | Session |
The _____ layer segments and reassembles data into a data stream | Transport |
Services located in the
_______ layer segment and reassemble data from upper-layer applications and unite it into
the same data stream | Transport |
What type of networking means that
acknowledgments, sequencing, and flow control will be used? Reliable or Unreliable | reliable. This can be used at the transport layer |
____ ______ prevents a sending host
on one side of the connection from overflowing the buffers in the receiving host—an event that
can result in lost data | Flow control.Data integrity is ensured at the Transport layer by maintaining flow control and by allowing
users to request reliable data transport between systems |
Reliable data transport employs a ______-oriented communications
session between systems | connection. |
Connection Oriented Communications ensure that The segments delivered are ______ back to the sender upon their reception | acknowledged.Any segments not acknowledged are retransmitted. |
The purpose of flow control is to provide a means for the _______ to govern
the amount of data sent by the ______. | receiver
sender |
In reliable transport operation, a device that wants to transmit sets up a connection-oriented
communication with a remote device by creating a session. The transmitting device 1st establishes a connection-oriented session w/its peer system,which is_ _ _ | three way handshake |
“connection agreement” segment is a request for synchronization. is the what step of the 3 way handshake? | 1 |
The second and third segments acknowledge the request and establish connection
parameters—the rules—between hosts. is the what step of the 3 way handshake? | 2 |
These segments request that the receiver’s
sequencing is synchronized here as well so that a bidirectional connection is formed. At what step of the 3 way handshake does this happen? | 2 |
The final segment is also an acknowledgment. It notifies the destination host that the connection
agreement has been accepted and that the actual connection has been established.
Data transfer can now begin.( what step of 3 way handshake is this?) | 3 |
A service is considered _______-________ if it has the following characteristics:
A virtual circuit is set up (e.g., a three-way handshake).
It uses sequencing.
It uses acknowledgments.
It uses flow control | connection-oriented |
The types of ____ ______ are buffering, windowing, and congestion
avoidance. | flow control |
The quantity of data segments (measured in bytes)
that the transmitting machine is allowed to send without receiving an acknowledgment for
them is called a ______ | window.Windows are used to control the amount of outstanding, unacknowledged
data segments. |
If a receiving host fails to receive all the segments that it should acknowledge, the
host can improve the communication session by decreasing the _______ size. | window |
First, when a packet is received on a router interface, the _____ _____ ______ is checked | destination IP
address |
What type of packets are used to transport user data through the internetwork.? | data packets |
What type of packets are used to update neighboring routers about the networks connected to and to help build and maintain routing tables on each router
all routers within the internetwork? | Route update packets |
Protocols that send route update packets are called _____
protocols | routing.examples of some common ones are RIP, RIPv2, EIGRP, and OSPF |
Protocols used to support
data traffic are called _____protocols | routed .examples of routed protocols are IP and IPv6. |
each VLAN
is a separate ______ domain | broadcast |
What OSI layer does this describe? File,Print, Message Database,and application services. | Application |
What OSI layer does this describe? Data encryption,compression,and translation services. | Presentation |
What OSI layer does this describe? Dialog Control | Session |
What OSI layer does this describe? End-to-end connection | Transport |
What OSI layer does this describe? Routing | Network |
What OSI layer does this describe? Framing | Datalink |
What OSI layer does this describe? Physical Topology | Physical |
A service is considered ______ -______ if it has the following characteristics:
A virtual circuit is set up (e.g., a three-way handshake).
It uses sequencing.
It uses acknowledgments.
It uses flow control. | connection-oriented |
The ____ layer manages device addressing, tracks the location of devices
on the network, and determines the best way to move data | Network.the Network layer
must transport traffic between devices that aren’t locally attached. Routers (layer 3 devices) are
specified at the Network layer and provide the routing services within an internetwork. |
Two types of packets are used at the Network layer?_____ and_______ _______ | data and route updates |
Within a router table the ____ is the The distance to the remote network. | Metric |
Within a routing table, the _____ is the exit interface a packet will take when destined for a specific network. | Interface.Each interface in a router represents a separate network.it must
be assigned unique network identification numbers, and each host on the network connected
to that router must use the same network number. |
What is the
number of routers a packet passes through en route to a remote network called? | hop count |
Routers, by default, will or will not forward any broadcast or multicast packets. | will not |
Routers use the _____ address in a Network layer header to determine the next hop
router to forward the packet to. | logical |
Routers can use ____ ______, created by an administrator, to control security on the types
of packets that are allowed to enter or exit an interface. | access lists |
_____ can provide layer 2 bridging functions if needed and can simultaneously route
through the same interface. | Routers |
Layer 3 devices (routers in this case) provide connections between virtual LANs (VLANs). | |
Within a routing table, the _____ is the exit interface a packet will take when destined for a specific network. | Interface.Each interface in a router represents a separate network.it must
be assigned unique network identification numbers, and each host on the network connected
to that router must use the same network number. |
What is the
number of routers a packet passes through en route to a remote network called? | hop count |
Routers, by default, will or will not forward any broadcast or multicast packets. | will not |
Routers use the _____ address in a Network layer header to determine the next hop
router to forward the packet to. | logical |
Routers can use ____ ______, created by an administrator, to control security on the types
of packets that are allowed to enter or exit an interface. | access lists |
_____ can provide layer 2 bridging functions if needed and can simultaneously route
through the same interface. | Routers |
Layer 3 devices (routers in this case) provide ______ between virtual LANs (VLANs). | connections |
_____ can provide quality of service (QoS) for specific types of network traffic | Routers |
The _____ _____ layer provides the physical transmission of the data and handles error
notification, network topology, and flow control. | Data Link |
the Data Link layer
will ensure that messages are delivered to the proper device on a LAN using ______
addresses and will translate messages from the Network layer into ___ for the Physical
layer to transmit. | hardware bits |
The Data Link layer formats the message into pieces, each called a data _____ and adds a customized
header containing the hardware destination and source address | frame |
It’s the ___ ____
layer that’s responsible for the actual unique identification of each device that resides on a
local network | Data Link |
the ____ itself is never altered along the route; it’s
only encapsulated with the type of control information required for it to be properly passed on to
the different media types | packet |
The IEEE Ethernet Data Link layer has two sublayers and one of them called ____ ____ ____ Defines how packets are placed on the media.Line discipline,
error notification, ordered delivery of frames, optional flow control can be used at this sublayer. | Media Access Control (MAC) 802.3.Physical addressing is defined here, as well as logical topologies |
_____ topology is the signal path through a physical topology | Logical |
The IEEE Ethernet Data Link layer has two sublayers and one of them called ____ _____ ____ is responsible for identifying Network layer protocols and
then encapsulating them. | Logical Link Control (LLC) 802.2.An LLC header tells the Data Link layer what to do with a packet
once a frame is received. |
The switches and bridges work at the
Data Link layer and filter the network using _____ addresses | hardware (MAC) addresses. |
Layer 2 switching is considered hardware-based bridging because it uses specialized hardware
called an | application-specific integrated circuit (ASIC). |
_____ is the time measured from when a frame enters a port to the time it
exits a port | Latency |
Bridges and switches read each frame as it passes through the network. The layer 2 device
then puts the source hardware address in a ____ table and keeps track of which port the frame
was received on. | filter. This helps
the machine determine the location of the specific sending device |
layer 3 machines (such
as routers) need to locate specific _____ | networks |
layer 2 machines (switches and bridges)
need to eventually locate specific _____ | devices |
When a switch interface receives a frame with a destination hardware address that isn’t found
in the device’s filter table, what will it do? | It will forward the frame to all connected segments.If the unknown
device that was sent the “mystery frame” replies to this forwarding action, the switch updates
its filter table regarding that device’s location |
What layer does this describe? It sends bits and receives bits.specifies the electrical, mechanical, procedural, and functional requirements
for activating, maintaining, and deactivating a physical link between end systems. | Physical |
This
layer is where you identify the interface between the data terminal equipment (DTE) and
the data communication equipment (DCE). | Physical |
A ____ is really a multiple-port repeater. A repeater receives a digital signal and reamplifies or
regenerates that signal and then forwards the digital signal out all active ports without looking
at any data | Hub |
______ is a contention media access method that allows all hosts on a network to share the
same bandwidth of a link | Ethernet |
Ethernet networking uses _____,
a protocol that helps devices share the bandwidth evenly without having two devices transmit at
the same time on the network medium. | Carrier Sense Multiple Access with Collision Detection (CSMA/CD) |
Explain what happens with CSMA/CD on an Ethernet LAN.... | A jam signal informs all devices that a collision occurred.
The collision invokes a random backoff algorithm.
Each device on the Ethernet segment stops transmitting for a short time until the
timers expire.
All hosts have= priority to transmit |
the effects of having a CSMA/CD network sustaining heavy collisions: | Delay
Low throughput
Congestion |
Full-duplex Ethernet can be used in three situations: | With a connection from a switch to a host
With a connection from a switch to a switch
With a connection from a host to a host using a crossover cable
Full-duplex Ethernet requires a point-to-point connection when only two nodes
are present. |
There are no collisions in ____-duplex mode. | full |
A dedicated switch port is required for each ____-duplex node. | full |
The host _____ card and the switch port must be capable of operating in full-duplex mode. | network |
Ethernet at the Data Link layer is responsible 2 things.... | *for Ethernet addressing, commonly referred to
as hardware addressing or MAC addressing and for framing packets
received from the Network layer and preparing them for transmission on the local network
through the Ethernet contention media access method |
Ethernet addressing uses uses the Media Access Control
(MAC) address burned into each and every Ethernet network interface card (NIC). The MAC,
or hardware, address is a __-bit (_-byte) address written in a hexadecimal format. | 48,6 |
______ are used at the Data Link layer to encapsulate packets handed down from the Network layer
for transmission on a type of media access. | Frames |
function of Ethernet stations is to pass data frames between each other using a group
of bits known as a MAC frame format. This provides error _____ from a cyclic redundancy
check (CRC) | detection |
Encapsulating a frame within a different type of frame is called _______ | tunneling |
______ address is all 1s (or Fs in hex) and
is sent to all devices | broadcast |
______ address is sent only to a similar subset of nodes on a network | Multicast |
What type of cable is used to connect these ?
Host to switch or hub
Router to switch or hub | straight through |
What type of cable is used to connect these ?
Switch to switch
Hub to hub
Host to host
Hub to switch
Router direct to host | Cross over |
To communicate&exchange info,each layer uses ____ ____ ____
These hold the control information attached to the data at each layer of the model. usually
attached to the header in front of the data field but can also be in the trailer, or end, of it. | Protocol Data Units (PDUs). |
The Cisco hierarchical model...(The definition of the layers is logical, not physical.) The layer that provides the backbone is the ____ | Core.layer is
responsible for transporting large amounts of traffic both reliably and quickly.The core is likely to see large volumes of traffic, so speed and latency
are driving concerns here. |
The Cisco hierarchical model... (The definition of the layers is logical, not physical.)The layer that provides the routing is the what layer? | Distribution |
The Cisco hierarchical model... (The definition of the layers is logical, not physical.)The layer that provides the switching is the what layer? | Access |
The primary functions of the _______(cisco hierarchical model)
layer are to provide routing, filtering, and WAN access and to determine how packets can
access the core, if needed | Distribution |
These things should be done at which layer of the hierarchical model? Routing
Implementing tools (such as access lists), packet filtering, and queuing
Implementing security and network policies, including address translation and firewalls | Distribution |
These things should be done at which layer of the hierarchical model? Redistributing between routing protocols, including static routing
Routing between VLANs and other workgroup support functions
Defining broadcast and multicast domains | Distribution |
In the cisco hierarchical model, the ____ layer controls user and workgroup access to internetwork resources. | Access |
These function should occur at what layer of the Cisco Hierarchical Model?
-Creation of separate collision domains (segmentation)
-Workgroup connectivity into the distribution layer
Continued (from distribution layer) use of access control and polici | Access.Technologies such as DDR and Ethernet switching are frequently seen in the access layer.
Static routing (instead of dynamic routing protocols) is seen here as well. |