Cisco CCNA Networking for Beginners
Сетевые технологии / Книги для мобильных устройств
Основная информация:
Название: Cisco CCNA Networking for Beginners
Жанр: Нет
Автор: Kumar Janglu
Год выпуска: 2020
Формат: PDF, EPUB
Размер: 15.2 MB
ISBN: 912726041255
Язык: Английский
СКАЧАТЬ Cisco CCNA Networking for Beginners БЕСПЛАТНО EPUB - DOC - DJVU - RTF - PDFОписание: Networks and networking have grown exponentially over the last 15 years understandably so. They have had to evolve at light speed just to keep up with huge increases in basic mission-critical user needs such as sharing data and printers as well as more advanced demands such as videoconferencing. Unless everyone who needs to share network resources is located in the same office are which is an increasingly uncommon situation, the challenge is to connect the sometimes many relevant networks together so all users can share the network’s wealth.
The application layer of the OSI model marks the spot where users actually communicate to the computer. This layer only comes into play when it’s apparent that access to the network is going to needed soon. Take the case of Internet Explorer (IE). You could uninstall every trace of networking components from a system, such as TCP/IP, NIC cards, and so on, and you could still use IE to view a local HTML document without any problem. But things would definitely get messy if you tried to do something like view an HTML document that must be retrieved using HTTP or nab a file with FTP or TFTP. That’s because IE will respond to requests such as those by attempting to access the Application layer. And what’s happening is that the Application layer is acting as an interface between the actual application program which isn’t at all a part of the layered structure and the next layer down by providing ways for the application to send information down through the protocol stack. In other words, IE doesn’t truly reside within the Application layer it interfaces with Application layer protocols when it needs to deal with remote resources.