Mobile communication Mobile Networking.pptx

Mobile communication

1. Mobile Networking

2. In general we will define what a mobile network is and how this type of network aims to provide connectivity for users. We will also discuss how a mobile network differs from other networks, such as wireless networks. Wireless technologies which provide communications between devices, for example, a laptop maybe connected wirelessly to a printer via radio using the Bluetooth standard.

3. What is a Mobile Network? Many people believe that when you say 'mobile network' you are referring to a wireless network. In actuality, a mobile network and a wireless network are two different types of networks . A mobile network can be defined as a communications network that is spread out over an immense land area around the world, connected wirelessly by transceivers at fixed locations that are known as  cell sites  or base stations. Transceivers :- communicate wirelessly based on the old principle of radio signals. Radio signals are electromagnetic radiation that includes light and infrared waves. These signals are considered to be transverse waves in that they have a frequency and a wavelength.

4. Continued.. Wavelengths :- A re measured in the distance between the peaks of sequential waves and the frequency is the number of cycles per second. To calculate the speed of a transverse wave, you multiply the wavelength and the frequency. Figure 1 below depicts the direction of travel of a radio signal, the wavelength and the amplitude .

5. How Mobile and Other Networks Differ As stated previously, many people think that a mobile network and a wireless network are one in the same. While they perform similar functions, they are completely different networks. A mobile network commonly is described as a physical device that can be taken anywhere as outlined in Figure. It is composed of a battery to provide power and must have some type of mobile network connectivity in order for the device to operate in order to send and receive data without having to attach the device to a hardware base.

6. Continued… In the case of wireless, this does not mean a physical device. Wireless mean having access to a wireless network such as a local area network (LAN), wide area network (WAN), or a 4G/3G cellular network . In instances like this, you take what used to connect through a router and cable and make that connection wireless. These types of networks still require some type of physical hardware within close proximity to have a physical connection to a power supply and a router or network node in order to communicate. A wireless network provides a fixed or portable endpoint to gain access to a distributed network. A mobile network, on the other hand, provides access to the distributed networks, through a portable device, that allows you to travel anywhere, as long as there is sufficient coverage.

7. Mobile networking devices Mobile IT devices  can use almost any wired and wireless networking technologies, as long as they are enabled to do so, either by in-built capability or via a network adapter. What are the different types of mobile network? Several different technologies exist that support  mobile networking , including: using the global system for mobile communications (GSM), general packet radio service (GPRS) and third-generation (3G) and fourth-generation (4G) services offered by mobile networks cable connection to 'wired' local area networks (LANs) - Ethernet is the most popular wired LAN technology secure 'wireless LANs' within office buildings or public 'hot spots' such as internet cafes - wireless fidelity (Wi-Fi) is the most popular wireless LAN technology Bluetooth or infra-red connection to another mobile device that offers one or more of the above connection capabilities extranets that can be accessed remotely, allowing mobile staff to use limited areas of your business' website and data use of smartphones to facilitate instant email access

8. Applications of mobile networking Sometimes you don't need networking capability on the move. It might be sufficient to download and upload the information required at the start and end of the day from the office computer system. However,  real-time communication  with the office can be important in delivering business benefits, such as efficient use of staff time, improved customer service and a greater range of products and services delivered. Examples include: making presentations to customers, and being able to download product information to their network during the visit quotations and interactive order processing checking stock levels via the office network interacting with colleagues while travelling - sending and receiving emails, collaborating on responses to tenders, delivering trip reports in a timely manner

9. Medium Access Protocol The media access control (MAC) data transmission protocol sub-layer, also known as the Medium Access Control, is a sub layer of Data link layer specified in the seven layer OSI model (layer 2). The hardware that implements the MAC is referred to as Medium Access Controller. S everal medium access control (MAC) algorithms are specifically adapted to the wireless domain . Medium access control comprises all mechanisms that regulate user access to a medium using SDM , TDM, FDM, or CDM. Thus MAC is similar to traffic regulations in the highway/multiplexing. E. g. several vehicles use the same street crossing in TDM, which requires rules to avoid collisions; one mechanism to enforce these rules is traffic lights.

10. Continued.. MAC belongs to layer 2, the data link control layer (DLC) . Layer 2 is subdivided into the logical link control (LLC ) , layer 2b, and the MAC, layer 2a. The task of DLC is to establish a reliable point to point or point to multi-point connection between different devices over a wired or wireless medium . LLC and MAC sub-layers

11. Continued…… The MAC sub-layer acts as an interface between the Logical Link Control (LLC) sub-layer and the network’s physical layer. The MAC layer emulates a full-duplex logical communication channel in a multi-point network. This channel may provide unicast, multicast or broadcast communication service.