Chapter 4 Mod 1: Understanding Computer Networking Flashcards
Understanding Computer Networking, Network Threats and attacks, Understanding Network Security Infrastructure
What is the basic definition of a network?
A network is a connection between two or more computers that allows them to share data, information, or resources.
What is crucial for establishing secure data communications?
o establish secure data communications, it is important to explore technologies in computer communications, including hardware, software, protocols, encryption, and other related details, standards, and procedures.
How many basic types of networks are there, and what are they?
There are two basic types of networks: Local Area Network (LAN) and Wide Area Network (WAN).
What does LAN stand for, and what does it typically span?
LAN stands for Local Area Network, and it typically spans a single floor or building, representing a limited geographical area.
What does WAN stand for, and what is its usual scope?
WAN stands for Wide Area Network, and it refers to long-distance connections between geographically remote networks.
What aspects need to be considered for secure data communications?
To ensure secure data communications, one must consider hardware, software, protocols, encryption, and various details, standards, and procedures involved in computer communications.
What is the primary function of hubs in a network?
Hubs are used to connect multiple devices in a network.
Where are hubs less likely to be seen, business networks, or home networks?
Hubs are less likely to be seen in business or corporate networks than in home networks.
Are hubs wired or wireless devices?
Hubs are wired devices.
In comparison to switches and routers, how intelligent are hubs?
Hubs are not as smart as switches or routers.
What is suggested as an alternative to using a hub in a network?
An alternative to using a hub is a switch, also known as an intelligent hub.
How do switches differ from hubs in terms of addressing devices?
Switches know the addresses of the devices connected to them and route traffic to specific ports/devices, unlike hubs that retransmit to all devices.
What type of devices are switches?
Switches are wired devices.
In comparison to hubs, are switches considered smarter?
Yes, switches are considered smarter than hubs.
Are switches as smart as routers?
No, switches are not as smart as routers.
How do switches contribute to greater efficiency in traffic delivery?
Switches improve the overall throughput of data by routing traffic to specific ports/devices based on addresses, enhancing traffic delivery efficiency.
What additional feature do switches have in terms of creating separate broadcast domains?
Switches can create separate broadcast domains when used to create VLANs (Virtual Local Area Networks).
What is the primary function of routers in a network?
Routers are used to control traffic flow on networks.
How are routers commonly employed in connecting networks?
Routers are often used to connect similar networks and control traffic flow between them.
Can routers be both wired and wireless devices?
Yes, routers can be both wired or wireless devices.
What is the capability of routers regarding switches?
Routers can connect multiple switches.
In comparison to hubs and switches, how intelligent are routers?
Routers are smarter than hubs and switches.
What role do routers play in determining traffic flow across a network?
Routers determine the most efficient “route” for traffic to flow across the network.
What is the primary role of firewalls in network management?
Firewalls are essential tools for managing and controlling network traffic and protecting the network.
Where is a firewall typically deployed in a network architecture?
A firewall is typically deployed between a private network and the internet.
In addition to being placed between a private network and the internet, where else can firewalls be deployed?
Firewalls can also be deployed between departments (segmented networks) within an organization that forms the overall network.
How does a firewall filter network traffic?
Firewalls filter traffic based on a defined set of rules, also known as filters or access control lists.
What is the purpose of filters or access control lists in firewalls?
Filters or access control lists in firewalls define the rules based on which traffic is filtered, allowing for the control and management of network traffic.
What is the primary function of a server in a network?
A server is a computer that provides information to other computers on a network.
Can you name some common types of servers? (4)
Common types of servers include web servers, email servers, print servers, database servers, and file servers.
How are servers typically accessed?
Internet file servers are accessible via FTP and HTTP protocols, while file servers on LAN, such as the ones used in offices and schools, are accessed using SMB or NFS protocol
How are servers usually secured in comparison to workstations?
Servers are usually secured differently than workstations to protect the information they contain.
Are servers designed to be networked?
Yes, servers are designed to be networked.
What are endpoints in the context of a network communication link?
Endpoints are the ends of a network communication link.
Where is one end of an endpoint often located, and what is its role?
One end of an endpoint is often at a server where a resource resides.
What is the role of the other end of an endpoint?
The other end of an endpoint is often a client making a request to use a network resource.
What are some examples of devices that can serve as endpoints?
Examples of devices that can serve as endpoints include another server, desktop workstation, laptop, tablet, mobile phone, or any other end-user device.
What does Ethernet (IEEE 802.3) define?
Ethernet is a standard (IEEE 802.3) that defines wired connections of networked devices.
What does IEEE 802.3 define?
Ethernet is a standard (IEEE 802.3) that defines wired connections of networked devices.
What is the purpose of the Ethernet standard?
The Ethernet standard defines the way data is formatted over the wire to ensure disparate devices can communicate over the same cables.
What is a MAC address, and how is it structured?
A MAC (Media Access Control) address is assigned to every network device. It is structured in the form of six pairs of hexadecimal digits, such as 00-13-02-1F-58-F5. The first 3 bytes (24 bits) denote the vendor or manufacturer of the physical network interface.
What happens if two devices have the same MAC address in the same local network?
If two devices have the same MAC address in the same local network, an address conflict occurs.
How are MAC addresses typically assigned?
MAC addresses are assigned in the firmware of the network interface.
What is an IP address, and what does it represent?
An IP (Internet Protocol) address is a unique logical address associated with a network device. It represents the network interface within the network.
In what situations can a IP address be useful?
A IP address can be useful to maintain communications when a physical device is swapped with new hardware.
Can you provide examples of both MAC and IP addresses?
An example of a MAC address is 00-13-02-1F-58-F5. Examples of IP addresses are 192.168.1.1 and 2001:db8::ffff:0:1.
How many layers does a network model have in its most basic form
A network model in its most basic form has at least two layers.
What is the upper layer of a network model responsible for, and what is it also known as?
The upper layer, also known as the host or application layer, is responsible for managing the integrity of a connection, controlling the session, establishing, maintaining, and terminating communication sessions between two computers. It is also responsible for transforming data received from the Application Layer into a format that any system can understand and allowing applications to communicate.
What is the lower layer of a network model often referred to as, and what is its responsibility?
The lower layer is often referred to as the media or transport layer, and it is responsible for receiving bits from the physical connection medium and converting them into a frame. Frames are grouped into standardized sizes.
What is added to the frames of data in the lower layer to create packets?
Route data is added to the frames of data in the lower layer to create packets. In other words, a destination address is added to the bucket.
Once the buckets of data are sorted and ready to go, what layer takes over?
Once the buckets of data are sorted and ready to go, the host layer takes over.
Why was the OSI Model developed?
The OSI Model was developed to establish a common way to describe the communication structure for interconnected computer systems.
How does the OSI model serve as a reference?
The OSI model serves as a model for how protocols should function in an ideal world, on ideal hardware.
It is used to understand the communication of various hierarchical components from software interfaces to physical hardware.
How many layers does the OSI model divide networking tasks into?
The OSI model divides networking tasks into seven distinct layers.
How are the layers of the OSI model ordered, and why?
The layers of the OSI model are ordered specifically to indicate how information flows through the various levels of communication.
1) Physical
2) Data Link
3) Network
4) Transport
5) Session
6) Presentation
7) Application
(Please Do Not Touch Sam’s Pet Alligator)
Each layer communicates directly with the layer above and the layer below it.
What is encapsulation, and when is it particularly important in the OSI model?
Encapsulation is the addition of header and possibly a footer (trailer) data by a protocol used at that layer of the OSI model. It is particularly important when discussing Transport, Network, and Data Link layers (2-4), which generally include some form of header.
What is the process known as when data moves up the OSI model layers from Physical to Application?
The process is known as de-encapsulation (or decapsulation).
How does the data unit size change as it moves down the OSI model? (Application to Physical)
The data unit size increases as it moves down the OSI model, and the contents continue to encapsulate.
What are some examples of networking terminology mapped to the OSI Model?
Examples include:
JPEG or PNG image files are associated with the Presentation Layer (6).
Logical ports such as NetBIOS are associated with the Session Layer (5).
TCP/UDP is associated with the Transport Layer (4).
Routers sending packets are associated with the Network Layer (3).
Switches, bridges, or WAPs sending frames are associated with the Data Link Layer (2).
What is TCP/IP, and when was it developed in comparison to the OSI model?
TCP/IP is the most widely used protocol today and was developed in the early 1970s, predating the development of the OSI model, which occurred in the late 1970s.
How does the TCP/IP protocol stack differ from the OSI model in terms of layers?
The TCP/IP protocol stack has four layers: Application Layer, Transport Layer, Internet Layer, and Network Interface Layer.
What is the focus of the TCP/IP protocol stack?
The TCP/IP protocol stack focuses on the core functions of networking.
