Section 1- Exploring Functions of Networking Flashcards
What are the devices at the bottom of a networking branch called?
Endpoint devices
Name examples of endpoint devices
- PCs
- Laptops
- File servers
- Printers
- IP phones
- Sensors
- Cameras
- Manufacturing robots
- Are examples of ‘—’ devices at the end of a network branch
Interconnections
Interconnections are…
components that connect devices on the network,
providing means for data to travel from
one point to another in the network.
components that connect the devices on the network, providing a means for data to travel from one point to another in the network.
Name 3 interconnection components
- NICs
- Network media
- Connectors
NIC
- Compound terms
- What it does
- Where it’s found
- How it (physically) connects to a network
- Network Interface Card/Controller
- Translates computer data into format that can be transmitted over a network
- On PC, laptop
- A NIC is the device on a PC into which you plug a network cable.
Network Media
- What it does
- Name the plural of ‘Media’
- provide the means by which
signals are transmitted from
one network device to another
- ‘Medium’
Name 3 types of Network Media
- Copper cabling
- Fiber-optic cabling
- Wireless connections
Connectors
- What type of component is this?
- What it does
- Name the most common network connector and number of wires it has
- Interconnection component
- Provides connection point for the media
- RJ-45, 8
Switches
- Define
- Devices that communicate via switch share a ‘—’ network
- Can devices on switch communicate with other networks?
- Allow endpoint devices to communicate directly with ea other
- Common network
- No, you need a router to communicate with outside networks
What are 2 limitations of hubs compared to switches?
- Performance
- Speed
- Are limitations to this device, compared to switches
Routers
- What they do
- Their main function
- connect networks and intelligently choose the best paths between networks
- Their main function is to route traffic from one network to another
- This network device is called…
WLAN Devices
- What do they connect?
- Name 2 WLAN devices
- Wireless devices to the network
- a) NIC b) WLAN AP
What are the 2 minimum requirements for wireless access to the network?
- Device w/ a wireless NIC
- WLAN AP (connected to traditional wired network)
- are the 2 minimum requirements for this type of connection to a network
APs
- Compound Terms
- What do they connect to?
- Can also be an integrated component in what device?
- Access Points
- Allows wireless devices to connect to a wired network
- Router
Firewalls
- Define
- Establishes barrier between what two types of networks?
- These devices are network security systems that
monitor and control the incoming and outgoing network traffic
based on predetermined security rules.
- A trusted, secure internal network and an insecure, untrusted external network (i.e. the Internet)
Multipurpose Device/ Router
- Define
- What 3 devices are integrated into a MpD/R?
- Explain characteristics of 3 devices integrated into MpD/R
- provides connectivity for wired and wireless devices as well as providing access to the Internet.
- Switch, router, WLAN AP
- Acts as a switch by providing physical ports to plug local devices into.
Acts as a WLAN AP by allowing wireless devices to connect to it.
Acts as a router by connecting the local network to the Internet.
Name the 7 Characteristics of Networks
- Topology
- Speed
- Cost
- Security
- Availability
- Scalability
- Reliability
Characteristics of Networks:
Topology
In networks, there are physical and logical topologies.
The physical topology is the arrangement of cables, network devices, and end systems.
- a physical topology describes how the network devices are actually interconnected with wires and cables
The logical topology is the path over which the data is transferred in a network.
- A logical topology describes how the network devices appear connected to network users.
Characteristics of Networks:
Speed:
Speed is a measure of the data rate in bits per second of a given link in the network.
Characteristics of Networks:
Cost
Cost indicates the general expense for the
(a) purchasing of network components and the
(b) installation and maintenance of the network.
Characteristics of Networks:
Security
Security indicates how protected the network is,
including the information that is transmitted over the network.
Characteristics of Networks:
Availability
A measure of the probability that the network will be available for use when it is required.
For networks that are meant to be used 24 hours per day, 7 days per week, 365 days per year,
availability is calculated by dividing the time that it is actually available by the total time in a year and then multiplying by 100 to get a percentage.
Name the Formula to Calculate:
Percentage of Network Availability
(Number of minutes in a year – down time) X 100
(number of minutes in a year)
Characteristics of Networks:
Scalability
indicates how easily the network can accommodate more users and data transmission requirements.
If you design and optimize a network for only the current requirements, it can be very expensive and difficult to meet new needs when the network grows.
Characteristics of Networks:
Reliability
indicates the dependability of the components that make up the network,
such as routers, switches, PCs, and servers.
Reliability is often measured as a probability of failure or as MTBF*.
*Mean Time Between Failures
Define
Physical Topology
the arrangement of cables, network devices, and end systems.
Define
Logical Topology
the path along which data travels from one point in the network to another
List
4 primary physical topology categories (shapes)
- Bus
- Ring
- Star
- Mesh
Define
Bus Topology
Every workstation connected to the main cable.
Each workstation directly connected to every other workstation in network.
- Early bus topologies cabled endpoint devices using coaxial cable.
- Modern bus topologies establish bus in hardware device, & connect host devices to bus using twisted-pair wiring.

Define
Ring Topology
Computers and network devices are cabled together so that
the last device is connected to the first to form a circle/ring.
Each device connected to exactly two neighbors
& has no direct connection to a third.
- Physical connection made using either coaxial or fiber wiring.

Define
Star Topology
A central cabling device connects the computers and other network devices.
Physical connection commonly made using twisted-pair wiring.
- Most common physical topology
- This category includes star and extended star topologies.
- Star topology is also known as hub-and-spoke topology, due to the shape of the design.

Define
Mesh Topology
every network device cabled together with many others.
- Redundant links increase reliability and self-healing.
- Physical connection commonly made using fiber or twisted-pair wiring.

Contrast between
Physical and Logical Topologies
It is possible the logical and physical topology of a network to be of the same type.
However, physical and logical topologies often differ.
- Ethernet hub is an example of a physical star topology with a logical bus topology.
- Physically hub is star topology; several hosts physically cabled with twisted-pair cables to centralized hub.
- Logically, hub is a bus topology; when any host transmits a packet, all devices plugged into hub will receive transmission as if all connected by same single coaxial cable.
- Below is a diagram depicting logical topology between ‘PC A’ and ‘Server’.
- In this example, packets do not follow shortest physical path
- Logical topology requires packets to travel through router in order for two devices to communicate.

Define/ Illustrate/ Interpret
Network Diagram
One of most important tasks when designing a network is creating a network diagram.
A map of network, illustrating logical representation of all devices in network and clarifies how they’re interconnected.
Proper diagram provides information such as interface IDs and network addressing.
Other information may be included in network diagram as space allows.
- Common to identify interface on a device:
- in the S0/0/0 format for a serial interface.
- Ethernet interfaces, Fa0/0 identifies Fast Ethernet interface
- Gi0/1 identifies Gigabit Ethernet interface.
- Also common to include network address of segment in 192.168.1.0/24 format.
- 192.168.1.0 indicates the network address, /24 indicates the subnet mask
- .1 and .2 at the device ends indicate IP addresses of the interfaces (.1 corresponds to 192.168.1.1).

How does/do . . .
Applications Affect Network Performance
Different type of applications differ in demands they put on the network.
(Increase) in Demand = (Decrease) in Network Performance
List
3 Types of Applications that Affect Network Performance
- Batch applications
- Interactive applications
- Real-Time applications
Define
Batch Applications
Applications that send and receive files
- Examples of batch applications:
- FTP
- TFTP
- No direct human interaction; once files selected and DL begins, user waits
- Bandwidth important but not critical b/c DL completed eventually even w low bandwidth
Define
Interactive Applications
Applications in which the user waits for a response, e.g. inventory lookup
- Human-to-machine interaction
- Human waiting for response; response time important more important than batch apps, but not critical, unless waiting becomes excessive
Define
Real-Time Applications
Voice & video applications that involve human-to-human interaction
- Due to amt of info being transmitted, bandwidth is critical
- Maximum throughput essential as RTA’s do not retransmit lost data
- End-to-end latency critical
Define
Latency
Amount of time for data to travel fom source to destination i.e. speed
Affected by:
- Physical Distance
- Physical elements in channel used to transmit data:
- Transmission mediums
- Propagation (transmission)
- Routers
- Storage Delays
Define
Bandwidth
The maximum amount of data that can travel through a ‘channel’
- Width of communication band
- Not used to measure speed but capacity
- High bandwidth =/= high network performance
- If throughput affected by latency/packet loss/ jitters, service will see delays despite substantial amt of bandwidth available
Define
Throughput
Measure rate at which messages arrive at destination successfully
- Also measured in (-)b/s
- Measuring low throughput indicates probs like packet loss where packets are lost in transit (devastating to VoIP audio calls where audio skips)
Example of:
The Difference Between Bandwidth, Latancy, & Throughput
Bandwidth determines how narrow or wide a pipe is. The narrower it is, the less data is able to be pushed through it at once and vice-versa.
Latency determines how fast the contents within a pipe can be transferred from the client to the server and back.
Throughput is the amount of data which can be transferred over a given time period.
- Latency affects throughput
- Bandwidth does not affect latency and throughput and vice versa