The Bits and Bytes of Computer Networking Week 1
Hubs and Switches: What's a router?
A router connects independent networks by forwarding data between them.
The simplest way to think of a server, is as?
The simplest way to think of a server, is as something that provides data to something requesting that data.
The thing receiving the data, is referred to as a----
The thing receiving the data, is referred to as a client. While we often talk about nodes being servers or clients, the reason our definition uses a word as vague as something, is because it's not just nodes that can be servers or clients.
While a hub is a layer 1 device and a switch is a layer 2 device, a router operates at layer ----, a network layer.
While a hub is a layer 1 device and a switch is a layer 2 device, a router operates at layer 3, a network layer.
The TCP/IP Five-Layer Network Model
1. Physical 2. Data-link 3. Network 4. Transport 5. Application
Hubs and Switches: Which is older Cat 5, Cat 5e or Cat 6 cables?
Cat 5 is older and has been mostly replaced by Cat 5e and Cat 6 cables. 5e cables have mostly replaced those older Cat 5 cables because their internals reduces crosstalk.
Hubs and Switches: ----- cables, following even more strict specifications to avoid crosstalk, making those cables more expensive.
Cat 6 cables can transfer data faster and more reliably than Cat 5e cables can, but because of their internal arrangement, they have a shorter maximum distance when used at higher speeds.
Hubs and Switches: --------- are the primary devices used to connect computers on a single network, usually referred to as a LAN, or local area network.
Hubs and switches are the primary devices used to connect computers on a single network, usually referred to as a LAN, or local area network.
Which of the following is an example of a network layer (layer 3) protocol?
Internet Protocol, is the most common network layer protocol.
What does the physical layer of TCP/IP Five-Layer Network Model
It represents the physical devices that interconnect computers. This includes the specifications for the networking cables and the connectors that join devices together along with specifications describing how signals are sent over these connections.
Hubs and Switches: Most network cables used today can be split into two categories:
copper and fiber
A collection of networks connected together through routers is an
internetwork
What is the final layer, Application layer responsible for in the TCP/IP Five-Layer Network Model
the fifth layer is known as the application layer. There are lots of different protocols at this layer, and as you might have guessed from the name, they are application-specific. ex...Protocols used to allow you to browse the web or send receive email are some common ones. The protocols at play in the application layer will be most familiar to you since they are ones you probably interacted with directly before even if you didn't realize it.
Which of the following are examples of layers of our five-layer network model?
-The application layer -The physical layer The transport layer
What's the difference between a client and a server?
A client requests data, and a server responds to that request.
Hubs and Switches: -------- is when an electrical pulse on one wire is accidentally detected on another wire.
Crosstalk is when an electrical pulse on one wire is accidentally detected on another wire. The receiving end isn't able to understand the data causing a network error.
Hubs and Switches: What does LAN stand for?
LAN stands for Local Area Network.
Hubs and Switches: The higher quality specifications of a ---- cable make it less likely that data needs to be retransmitted.
The higher quality specifications of a Cat 5e cable make it less likely that data needs to be retransmitted. Higher-level protocols have methods for detecting missing data and asking for the data a second time, but of course, this takes up more time. That means on average, you can expect more data to be transferred in the same amount of time.
Which ----- layer is responsible for getting data across a single link
While the data link layer is responsible for getting data across a single link
Best way to explain the TCP/IP Five Layer Network Model
You can think of layers like different aspects of a package being delivered. First Layer: The physical layer is the delivery truck and the roads. Second Layer: The data link layer is how the delivery trucks get from one intersection to the next over and over. Third Layer: The network layer identifies which roads need to be taken to get from address A to address B. Fourth Layer: The transport layer ensures that delivery driver knows how to knock on your door to tell you your package has arrived. Fifth Layer: And the application layer is the contents of the package itself.
What does the Data-link, second layer, in charge of in the TCP/IP Five-Layer Network Model
2nd layer Some sources will call this layer the "network interface" or the "network access" layer. At this layer, we introduce our first protocols. While the physical layer is all about cabling, connectors and sending signals, the data link layer is responsible for defining a common way of interpreting these signals, so network devices can communicate. Lots of protocols exist at the data link layer, but the most common is known as Ethernet, although wireless technologies are becoming more and more popular. Beyond specifying physical layer attributes, the Ethernet standards also define a protocol responsible for getting data to nodes on the same network or link.
Hubs and Switches: Question 1 Which of the following statements accurately describe the differences between a hub and a switch?
A hub is a physical layer device, and a switch is a data link layer device. A switch remembers which devices are connected on each interface, while a hub does not. A hub causes larger collision domains.
What is a Node?
Any system or device connected to a network is also called a node. For example, if a network connects a file server, five computers, and two printers, there are eight nodes on the network. Each device on the network has a network address, such as a MAC address, which uniquely identifies each device.
Routers share data with each other via a protocol known as -------- that let's them learn about the most optimal paths to forward traffic.
BGP, or border gateway protocol, When you open a web browser and load a web page, the traffic between computers and the web servers could have traveled over dozens of different routers.
Hubs and Switches: The most common forms of copper twisted pair cables used in networking, are
Cat 5, Cat 5e, and Cat 6 cables, These are all shorthand ways of saying category 5 or category 6 cables. These categories have different physical characteristics, like the number of twists in the pair of copper wires that results in different usable lengths and transfer rates. The important thing to know is that differences in how the twisted pairs are arranged inside these cables can drastically alter how quickly data can be sent across them and how resistant these signals are to outside interference.
Hubs and Switches: ------cables are the most common form of networking cable.
Copper cables, They're made up of multiple pairs of copper wires inside plastic insulator. You may already know that computers communicate in binary, which people represent with ones and zeros. The sending device communicates binary data across these copper wires by changing the voltage between two ranges. The system at the receiving end is able to interpret these voltage changes as binary ones and zeros, which can then be translated into different forms of data.
Once traffic is at the ISP, a way more sophisticated type of router takes over. These ---- routers form the backbone of the Internet, and are directly responsible for how we send and receive data all over the Internet every single day.
Core Routers, Core routers don't just handle a lot more traffic than a home or small office router, they also have to deal with much more complexity in making decisions about where to send traffic. A core router usually has many different connections to many other routers. Routers share data with each other via a protocol known as BGP, or border gateway protocol, that let's them learn about the most optimal paths to forward traffic.
Just like a switch can inspect Ethernet data to determine where to send things, a router can do what?
Just like a switch can inspect Ethernet data to determine where to send things, a router can inspect IP data to determine where to send things. Routers store internal tables containing information about how to route traffic between lots of different networks all over the world.
The most common type of router you'll see is one for a -----.
The most common type of router you'll see is one for a home network or a small office. These devices generally don't have very detailed routing tables. The purpose of these routers is mainly just to take traffic originating from inside the home or office LAN and to forward it along to the ISP, or Internet service provider.
What does the network, third layer, in charge of in the TCP/IP Five-Layer Network Model?
The third layer is also sometimes called the Internet layer. It's this layer that allows different networks to communicate with each other through devices known as routers. A collection of networks connected together through routers is an "internetwork", the most famous of these being the Internet. While the data link layer is responsible for getting data across a single link, the network layer is responsible for getting data delivered across a collection of networks. Think of when a device on your home network connects with a server on the Internet. It's the network layer that helps gets the data between these two locations. The most common protocol used at this layer is known as IP or Internet Protocol. IP is the heart of the Internet and most small networks around the world. Network software is usually divided into client and server categories, with the client application initiating a request for data and the server software answering the request across the network. A single node may be running multiple client or server applications. So, you might run an email program and a web browser, both client applications, on your PC at the same time, and your email and web server might both run on the same server.
What does the Transport, fourth layer do in the TCP/IP Five-Layer Network Model
While the network layer delivers data between two individual nodes, the transport layer sorts out which client and server programs are supposed to get that data. When you heard about our network layer protocol IP, you may have thought of TCP IP, which is a pretty common phrase. That's because the protocol most commonly used in the fourth layer, the transport layer, is known as TCP or Transmission Control Protocol. While often said together as the phrase TCP IP, to fully understand and troubleshoot networking issues, it's important to know that they're entirely different protocols serving different purposes. Other transfer protocols also use IP to get around, including a protocol known as UDP or "User Datagram Protocol". The big difference between the two is that TCP provides mechanisms to ensure that data is reliably delivered while UDP does not. It's important to know that the network layer, in our case, IP is responsible for getting data from one node to another. Also, remember that the transport layer, mostly TCP and UDP, is responsible for ensuring that data gets to the right applications running on those nodes.
Hubs and Switches: How are cables used to help us in I.T.?
cables are what connect different devices to each other, allowing data to be transmitted over them.
Hubs and Switches: The second primary form of networking cable is known as ?
fiber, short for fiber-optic cables. Fiber cables contain individual optical fibers, which are tiny tubes made out of glass about the width of a human hair. These tubes of glass can transport beams of light. Unlike copper, which uses electrical voltages, fiber cables use pulses of light to represent the ones and zeros of the underlying data. Fiber is even sometimes used specifically in environments where there's a lot of electromagnetic interference from outside sources because this can impact data being sent across copper wires.
