Specify End devices, data transfer devices, transmission medium.
A computer network is a collection of computers and devices connected via communication devices and transmission media.
The main purpose of the network - a convenient and fast data exchange (of information) between devices.
- End Devices
- Intermediary Devices
- Network Media.
The network devices that people are most familiar with are called end devices. These devices form the interface between the human network and the underlying communication network. Someexamplesofenddevicesare:
• Computers (work stations, laptops, file servers, web servers)
Mobile handheld devices (such as wireless barcode scanners, PDAs
• Intermediary Devices network component or intermediate device is such a device that combine endpoints in local (or global) data network.
For intermediate devices include hubs (hubs), switches (switches, switches), routers (routers, routers), modems (modems), wireless access point (Wireless Access Point) and firewalls (firewalls, brendmauers).
Network Media - is a metal wire (copper twisted pair telephone cable), glass (glass), or even "air” (Bluetooth, Wi-Fi, 3G, LTE). By "air" shall mean the data transmission medium without wires, that is "wireless."
• When we go to the website, we (or rather, our browser) first sends a request to a web server where you store the files of the requested site, and have a special service (program the HTTP server) processes the request and sends us back the web page file which (web page) and we will see in the browser.
Services: Web server, mail-server, ftp-server.
Processes, unlike services are invisible to us, but they (the process) is much more important for us and our network. This process works day and night on the routers, switches, wireless access points and other network equipment.
Processes: special service network processes running on network equipment.
Local-area network (LAN)A network that connects a relatively small number of machines in a relatively close geographical area
Types of Networks
Various configurations, called topologies, have been used to administer LANs
• Ring topology A configuration that connects all nodes in a closed loop on which messages travel in one direction
• Star topology A configuration that centers around one node to which all others are connected and through which all messages are sent
• Bus topology All nodes are connected to a single communication line that carries messages in both directions
• Wide-area network (WAN) A network that connects two or more local-area networks over a potentially large geographic distance
Often one particular node on a LAN is set up to serve as a gatewayto handle all communication going between that LAN and other networks
Communication between networks is called internetworking
The Internet, as we know it today, is essentially the ultimate wide-area network, spanning the entire globe
• Metropolitan-area network (MAN) The communication infrastructures that have been developed in and around large cities
Specify Cyber security and control of the Internet
Cyber security or information technology security are the techniques of protecting computers, netwoks , programs and data from unauthorized access or attacks that are aimed for exploitation.Ensuring cybersecurity requires coordinated efforts throughout an information system.Elements of cybersecurity include:
· Application security
· Information security
· Network security
· Disaster recovery\ business continuity planning
· End- user education
Computer security is the protection of computing systems and the data that they store or access.In a computing context ,the term security implies cybersecurity.One of the most problematic elements of cybersecurity is the quickly and constantly evolving nature of security risks.
Describe Internet protocols: IP, TCP, DMP
. Describe Internet protocols: IP, TCP, DMP.
The Internet Protocol (IP) is the method or protocol by which data is sent from one computer to another on the Internet. Each computer (known as a host) on the Internet has at least one IP address that uniquely identifies it from all other computers on the Internet. This may be either an IPv4 or IPv6 address, but either way it uniquely defines a device on the Internet.
The Internet Protocol also provides basic instructions for transferring packets between devices. However, it does not actually establish the connection or define the ordering of the packets transmitted. These aspects are handled by the Transmission Control Protocol.
Transmission Control Protocol, which works in conjunction with the Internet Protocol to transfer data between systems on the Internet.
Transmission Control Protocol (TCP)
TCP is a connection oriented protocol and offers end-to-end packet delivery. It acts as back bone for connection.It exhibits the following key features:
· Transmission Control Protocol (TCP) corresponds to the Transport Layer of OSI Model.
· TCP is a reliable and connection oriented protocol.
· TCP offers:
o Stream Data Transfer.
o Efficient Flow Control
o Full-duplex operation.
· TCP offers connection oriented end-to-end packet delivery.
· TCP ensures reliability by sequencing bytes with a forwarding acknowledgement number that indicates to the destination the next byte the source expect to receive.
· It retransmits the bytes not acknowledged with in specified time period.
TCP offers following services to the processes at the application layer:
· Stream Delivery Service
· Sending and Receiving Buffers
· Bytes and Segments
· Full Duplex Service
· Connection Oriented Service
· Reliable Service
What is a data management platform ?
In simple terms, a data management platform is a data warehouse. It’s a piece of software that sucks up, sorts and houses information, and spits it out in a way that’s useful for marketers, publishers and other businesses.
This sounds like a database. Is it more?
In theory, DMPs can be used to house and manage any form of information, but for marketers, they’re most often used to manage cookie IDs and to generate audience segments, which are subsequently used to target specific users with online ads. With the rise of ad tech, advertisers now buy media across a huge range of different sites and through various middlemen, including DSPs, ad networks and exchanges. DMPs can help tie all that activity and resulting campaign and audience data together in one, centralized location and use it to help optimize future media buys and ad creative. It’s all about better understanding customer information.
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