ccna 200 301 book pdf free download

ccna 200 301 book pdf free download.Using 3G/4G for mobile phone accessMany of you reading this book have a mobile phone with Internet access. That means you can check your email, surf the web, download apps and enjoy videos. Most social media junkies rely on their mobile phones, and having Internet access installed into the phone allows most people to use features like Twitter. This section explores the big concepts behind the Internet access technology in these mobile phones.Mobile phones use a nearby mobile phone base station to communicate via radio waves. The phone has a small radio antenna, and somewhere within a few miles of you and your phone, the provider has a larger antenna mounted on top of the base station. Phones, desktop computers, laptops, and even routers (with the correct interface cards) can use this technology to communicate over the Internet, as shown in Figure 15-11.Figure 15-11 Wireless Internet access using 3G/4G technology13.2 Base Content 321 Mobile phone wireless base stations also have cables and equipment, including routers. The mobile provider builds its own IP network, just as an ISP builds out an IP network. Customer IP packets reach the mobile provider's IP network through the IP router at the base station and then enter the InternetoThe market for mobile phones and other wireless Internet access devices is huge and highly competitive. As a result, mobile operators spend a lot of money to advertise their services and come up with names for them. It is frankly difficult to tell what all the marketing terms mean, but certain terms are very popular throughout the industry. Wireless Internet:The basic term from a mobile phone or any Internet service that uses the same technology.Wireless 3G/4G: Short for third and fourth generation mobile communications. These terms refer to the major changes in the wireless networks of mobile phone companies over time. LTE: LongTermEvolution, a newer and faster technology that is inconveniently considered to be a fourth generation (4G) technology.To summarize from these terms, when you hear about wireless Internet services and also mention a mobile phone base station - whether the device is a phone, tablet or PC - chances are it's a 3G, 4G or LTE wireless Internet connection.Ethernet-based peer-to-peer protocols Before we conclude this chapter, let's leave WAN technology out of it and discuss a technology that is on top of some DSL connections: PPP over Ethernet (PPPoE). PPPoE ConceptsFirst, review what was discussed in Chapter 12 about PPP and CHAP. PPP is one of the data link protocols that operate over a point-to-point link, and the term "questioning handshake authentication protocol" (CHAP) supports authentication as part of PPP. PPP can be used for serial links, including those created by dial-up analog and ISDN modems. For example, a connection using an analog modem and coming from an ISP dial-up user is now likely to use PPP.