MOBILE COMPUTING HAND NOTE

OBJECTIVE

The objectives of the course are:

- To make the student understand the concept of mobile computing paradigm, its novel applications and limitations.

- To understand the typical mobile networking infrastructure through a popular GSM protocol.

- To understand the issues and solutions of various layers of mobile networks, namely MAC layer, Network layer, & Transport Layer

- To understand the database issues in mobile environments & data delivery models.

- To understand the ad hoc networks and related concepts.

- To understand the platforms and protocols used in mobile environment.

OUTCOMES

After completing this course, the student should be able to:

- Able to think and develop new mobile application

- Able to debate on any technical issue related to this new paradigm and come up with a solution(s).

- Able to develop new ad hoc network applications and/or algorithms/protocols.

- Able to explain & develop any existing or new protocol related to mobile environment.

>> WHAT IS MOBILE COMPUTING?

* A simple definition could be:

Mobile computing is using a computer (of one kind or another) while on the move.

* Another definition could be:

Mobile computing is when a (work) process is moved from a normal fixed position to a more dynamic position.

* A third definition could be:

Mobile computing is when a work process is carried out somewhere where it was not previously possible.

* A best definition could be:

Mobile computing is an umbrella term used to describe technologies that enable people to access network services anyplace, anytime, and anywhere.

* Mobile computing can be defined as a computing environment over physical mobility.

What is computing?

Operation of computers.

What is the mobile?

That someone/ something can move or be moved easily and quickly from place to place.

What is mobile computing?

Users with portable computers still have network connections while they move.

>> COMPARISON TO WIRED NETWORKS AND MOBILE NETWORKS?

=> * WIRED NETWORKS

- High bandwidth

- Low bandwidth variability

- Can listen on wire

- High power machines

- High resource machines

- Need physical access

- Low delay

- Connected operation

* MOBILE NETWORKS

- Low bandwidth

- High bandwidth variability

- Hidden terminal problem

- Low power machines

- Low resource machines

- Need proximity

- Higher delay

- Disconnected operation

>> TYPES OF WIRELESS DEVICES

* Laptops

* Palmtops

* PDAs

* Cell phones

* Pagers

* Sensors

>> CHALLENGES

* Disconnection

* Low bandwidth

* High bandwidth variability

* Low power and resources

* Security risks

* Wide variety terminals and devices with different capabilities (Device attributes)

* Fit more functionality into single, smaller device

MOBILITY

The user of a mobile computing environment will be able to access data, information or other logical objects from any device in any network while on the move.

* Mobility

1. User Mobility

2. Device Mobility

Anywhere, Anytime Information :

This is the generic definition of ubiquity, where the information is available anywhere, all the time.

Virtual Home Environment :

(VHE) is defined as an environment in a foreign network such that the mobile users can experience the same computing experience as they have in their home or corporate computing environment.

For example, one would like to put ones room heater on when one is about 15 minutes away from home.

Global Service Portability :

Making a service portable and available in every environment. Any service of any environment will be available globally.

Wearable Computers :

Wearable computers are those computers that may be adorned by humans like a hat, watch, shoe or clothes.

MOBILE COMPUTING FUNCTIONS

We can define a computing environment as mobile if it supports one or more of the following characteristics:

* User Mobility

* Network Mobility

* Device Mobility

* Service Mobility

* Bearer Mobility

* Session Mobility

* Host Mobility (client-server, ip)

Issues in Categories :

* Software Issues - Apps

* Technical Issues - Battery, H/W

* Network Issues - Connection

* User Interface Issues - Understanding

* Security Issues - Attacks

Future of Mobile Computing :

* Use of Artificial Intelligence

* Integrated circuitry -> Compact Size

* Increases in Computer Processor speeds

etc..

Still, Open Areas..

* Interference

* Regulations and Spectrum

* Low Bandwidth

* High delays, large delay variations

* Lower security, Simpler to attack

* Shared medium

* Adhoc networking

MOBILE COMPUTER ARCHITECTURE

//Tier 1 means Presentation tier, Tier 2 means Application tier, and Tire 3 means Data tire.

//Tier 1 shows to user. Tier 2 is internal application work. and Tier 3 is storing data in database.

A. PRESENTATION LAYER (Tier 1)

1. The layer of application that run on the client device and offer all the user interfaces.

2. It is responsible for presenting information to the end user.

3. Users receive information through screen, speaker, vibration.

4. User send information through keyboard, pen, touch screen.

5. It includes Web browsers, WAP (wireless access protocol) browser, customize client programs.

6. It should be context aware and device independent.

B. APPLICATION TIER (Tier 2)

1. It is the engine of the different application.

2. It performs business logic, processing user input, obtaining data, making decision, and transcoding of data for rendering in tier 1.

3. It includes technologies like Java, JSP, .Net services, PHP etc.

4. Presentation and Database independent.

5. Decision on rendering, Network management, Security, Data store access and need for different middle ware software.

6. A middleware can be categorized into message oriented middleware(MOM)

* It connects different application through asynchronous exchange of message. It is mainly peer-to-peer fashion.

* Database middleware: It runs in application and database. Example, DB connector as ODBC.

* Transcoding middleware: Transcode one format of data to another format for the need of the client. Example Internet content adoption protocol (ICAP), It transcode HTTP content.

* Distributed Object and Component : KORBA an open distributed object computing infrastructure. It simplifies common network programming task, object registration, location, activation, request multiplexing and error handling.

* Transaction processing middleware : It provides tools and environment for developing transaction based distributed application. It includes some management feature like restarting failed process, dynamic load balancing, and enforcing consistency of distributed data. It optimize the use of resources.

MIDDLE WARE: It is a software that provides a link between separate software application, mainly it is a layer that lies between the operating system and the application.

Types of Middleware: Communication middleware, Message oriented middleware, Object oriented middleware, Remote procedure call middleware, Database middleware, Transaction middleware, Embedded middleware, Content centric middleware.

GATEWAY: Gateway are required when the networks between the device and the middleware having different set of protocols. For example, IVR gateway is used to interface voice with a computer. WAP gateway is used to access internet on mobile phones.

C. DATA LAYER (Tier 3):

It is used to store data needed by the application and act as a repository for both temporary and permanent data.

Data can be stored in any form. Example : Relational DB, Text files etc.

SyncML : This protocol to standardize synchronization of data access from different node.

1. Mobile device work in an occasionally connected computing mode.

2. Access centralized resource from time to time.

3. Some data is cached in the local device and access frequently.

4. Access and update information on the fly.

************************************************************************************************************

SPREAD SPECTRUM

A collective class of signalling technique are employed before transmitting a signal to provide a secure communication known as SPREAD SPECTRUM MODULATION. The main advantage of spread spectrum communication technique is to prevent interference weather it is intentional or unintentional. The features of this modulation are given below,

- The band of signal occupy a wide range of frequencies.

- Power density is very low.

- Energy is widespread

With these features the spread spectrum signals are highly resistant to interference or jamming. Since multiple users can share the same spectrum bandwidth without interfering with one another this can be called as Multiple Access technique.

This spread spectrum techniques are two types: 1. Direct Sequence Spread Spectrum DSSS 2. Frequency hopping spread spectrum FHSS.

DSSS:

Whenever a user wants to send data using this technique each and every bit of user data is multiplied by a secret code called as chipping code these chipping code is nothing but spreading code which is multiplied with the original message and transmitted.

The receiver uses the same code to retrieve the original message.

FHSS:

This is a frequency ho, where the users are made to change the frequency of uses from one to another in a specified time interval hence called as frequency hopping. For example, the frequency was allotted to sender 1 for a particular period of time. now after a while sender 1 hops to the other frequency and sent it to use the first frequency which was previously used by sender one.this is called as frequency reuse.

The frequency of the data are hopped from one to another in order to provide a secure transmission. The amount of time spend on each frequency hop is called as Dwell time.

Comparison between DHSS and FHSS

DHSS | FHSS

Single frequency is used | multiple frequency is used

User frequency once allocation is always the same | hard to find the user freq at any instance of time

Sender has to wait if the spectrum is busy. | Sender need not wait.

Power straighten of the signal is low | Power straighten of the signal is high

It is expensive | it is cheaper

This technique is not frequently used | Commonly used technique.

*********************************************************************

GSM ARCHITECTURE

The GSM network comprises of many functional units, This functions and interface are explained in this part, The GSM network can be broadly divided into mobile station MS the base station subsystems BSS, the network switching subsystem NSS, operation support subsystem OSS.

Mobille station: The MS consist of physical equipment such as the radio transiver, display and digital signal processor and the sim card. The MS akso provides access to the various services available in GSM network, These data services include:

1. X.25 packet switching through a synchronous and asynchronous dial-up connection to the PAD(Portable access device) at speed typically at 9.6kbps.

General packet radio service GPRS using ip based data transfer method at the rate upto 115kbps.

High speed circuit switch data at 64kbps.

2. Base station subsystem BSS : The BSS is composed of two parts, a. the base transiver station(BTS) b. the base station controller.

BTS: the BTS houses radio transiver that defines a cell and handles the radio link protocol with the images. Each BTS surves as a single cell, IT also include the following fucntions.

1. Encoding, Encrypting, MultiPlexing, Modulating and Feeding the RF signal to the antenna.

2. Transcoding and data adaptaion

3. Time and frequncy synchoronuzing

4. Decoding, Decrypting and Equalizin received signal

5. Uplink channel massurement.

THE BASE STATION CONTROLER BST:

The BSC manages the radio resource for one or more BTS. It handle radio channel setup, frequncy hopping and handover.

The BSC is the connection between the mobile and MSC.

The additional function include

1.control of frequncy hopping.

2. performing traffic concentration to reduce the number of lines from the MSC.

3. Providing the interface to an operation and maintainance center for the BSS.

4. Power Management

5. Time and Frequncy synchronization

************************************************************************************

Satallite Communication

3 different types of Satallites are found

1. GEO (GeoStationary Earth Orbit)

2. MEO (Medium Earth Orbit)

3. LEO (Low Earth Orbit)

GEO

GEO at about 35,768 Km above the earth surface. Geo Stationary Satallite moves around the earth at

the same speed as the earth rotates. This means Geo Stationary satallite remains in the same position

relative to the surface of earth.

Advantage of GEO Satallite

1. 3 GEO Stationary Satallite are enough for A complete coverage of any spot on the earth

2. recivers and senders and use fixed Antenna positions, No adjusting is needed

3. Geo are ideal for TV and Radio Broadcasting

4. Lifetime of GEO is 15 Years

5. GEO Typically do not need handover due to large footprint(Coverage Area).

Disadvantage of GEO Satallite

1. Northern Or Southern Region of the earth have more problems Receiving these satallite, due to

low elevation above latitude of 60Deg, Larger antenna are needed in these case.

2. Transferring a GEO into Orbit is very expensive.

3. This satallite can not be used for small mobile phone.

MEO

1. MEO satallite situated in orbit somewhere between 6000 km to 20000 km above the earth

surface.

2. MEO Satallites are visible for much longer periods of time then LEO satallite.

3. MEO Satallites have a large coverage area than LEO.

4. MEO can be position somewhere between LEO and GEO.

Advantage of MEO Satallite

1. Using orbit around 10000 km, the system only requires a dozen satallite which is more than

GEO system but much less than LEO system.

2. In MEO satallites Longer duration of visibility and wider footprint means fewer satallites are

needed in the MEO Network.

Disadvantage of MEO Satallite

1. Again, Due to the large distance to the earth. Delay increase to 70 to 80 ms. The Satallites need

higher transmit power and special antenna for smaller footprint.

2. In MEO satallite distance gives it a longer time delay and weaker signal than LEO satallite.

LEO

1. As LEO Circulate on Lower Earth Orbit it is obvious that they exibit in much shorter period(The

typical duration are 95 to 120 minutes ). Additionally LEO System try to ensure a high Elevation

for every spot on Earth to provide a high quality communication LINK.

2. Each LEO satallite can only be visible from the earth for about 10 min.3. A Farther classification of LEO's into little LEO's(100 bit/sec) with low bandwidth service,

Big Leo(1000 bit/sec), and Broadband LEO with plans reaching into MBit/sec, range can be

found in 1997.

4. LEO Satallite are much closer to earth then GEO. Ranging from 500 to 15000 km above the

surface.

5. LEO Satallite do not stay in fixed position relative to the surface. and they are only visible

maximum 15 to 20 min each pass.

Advantage of LEO Satallite

1. Using Advance Comparison Skims, Transmission rates of about 2400 bits/sec can be enough for

voice communication.

2. LEO even provide its bandwidth for mobile terminals, with omnidirectional antennas using low

transmit powers in the range of 1 Watt.

3. IN LEO Satallite smaller area of coverage is waste of bandwidth.

4. using advance comparison skims transmission rate of about 2400 bit/sec can be enough for

voice communication not for video communication.

5. Smaller Footprint of LEO allow for better frequency use similar to the concept used in the

cellular network.

6. A LEO Satallite proximity to earth compared to a GEO Satallite gives a better signal strength and

less of time delay. Which makes it better for point to point communication.

Disadvantage of LEO Satallite

1. The Biggest Problem of LEO concept is the need for many satallites.

2. The High Number of Satallites combined with the first movement results in a high complexity of

the whole system the short time of visibility with a high elevation requires additional

machanism. For Connection Handover between different satallites.

3. The Low Latency via A Single LEO is only half of the coverage area.

4. Other factors are needed for routing of data packets from satallite to satallite, if a user want to

communicate around the world.

5. A GEO Typically does not need this type of routing as sender and reciver are most likely in the

same footprint.

************************************************************************************

DECT (Digital Enhanced Cordless Telecommunication)

DECT started its life as digital european cordless telephony in the late 80's and has seens then had two

name changes have reflected a more global deployment at a move to include data as well as voice

service.

DECT is well suited to both domestic and business use its dyanamic channel alocation and digital voice coding(TDMA) provide a voice quality comparable to a landline, while its ability to handover between base stations made DECT a prime candidate for larger size. Such as offices and industrial Building.

A US version of DECT has also been developed under the acronyms PWT operating in the 2.4Ghz ISN

band.

Characteristics of DECT

1. Frequency: 1880Mhz to 1900Mhz

2. Channel: 120 Full Duplex

3. Duplex Mechanizm: TDD(Time Division Duplex) with 10 ms Framelength.

4. Multiplexing Scheme: FDMA with 10 carrier frequency, TDMA with 2x12 Slots.

5. Modulation: GMSK(Gussian Minimum Shift Key), Digital

6. Power: 10MW - 250MW

7. Range: Approx 50 meter in building, 300meters in open space.

Satalite

A Communication Satalite is a Microwave Repeter Station in a Space that is used for telecommunication, Radio and Television Singal. A Comminication satalite process the data comming from one Earth Station and it converse the data into another form and send it into 2nd earth station.

How Satalite Works

Two Station on the Earth where to communicate through radio Broadcast but are too Far Away to use conventional Means. The two station can use the relay station for their communication. One earth station transmit the signal to the Satalite.

UPLINK Frequency is the Frequency at which ground station is communicating with satalite. The Satalite Transponder Converse the signal and send it down to the 2nd Earth Station. and this Called DOWNLINK Frequency. The 2nd Earth station communicate with the 1st in the same way.

Advantage of Satalite

1. The Coverage Area is very High then that of Terrestrial System.

2. The Transmission Cost is independent of the coverage Area.

3. High Bandwidth are possible.

Disadvantage of Satalite

1. Launching Satalite into orbit is a costly process

2. High Propagation Delay for Satalite System then the conventional System

3. the bandwidth are gradually used up

Satalite Frquency Band

The Satalite Frequency Band which are commonly used for communication are:

1. C Band

2. KU Band

3. K-A Band

C band and KU band are the commonly used frequency Spectrum by today's Satalite.

It is important to note that there is a inverse relationship between Frequency and Wavelength

When Frequency Increase Wavelength Decrease, this helps to understand the relationship Between

antana, Diameter and Transmission Frequency. Larger Antinas(Satalite Dishes) are necessary to gather

the signal with increasing wavelength.

Satalite Communication Basics

The Process of Satalite comminication begans at an Earth Station. There An Installation is Degisned to

Transmit and Recieve Signal from a satalite in orbit around the earth.

Earth Station send information to satalites in the form of high power, High Frequency(GHZ) Signals.

The Satalite Receive and Transmit the signal back to earth where they are received by other earth

station in the coverage area of the satalite. Satalite's Foot Print is the Area which receives a signal of

usefull strength from the Satalite. The Transmission System from the earth station to satalite through

a channel is called UP-LINK. The System from the Satalite to the Earth Station through the channel is

called DOWN-LINK.

************************************************************************************

802 Specification

802 Overview Basic of Physical and Logical networking concepts

802.1 Bridging LAN Bridging and Management Covers management and lower sub layers of OSI Layer 2, Including mac based bridging, Virtual LAN and Port based access control. This also contain the time sensitive networking task group.

802.2 Logical Link Disbanded

802.3 Ethernet Provide Asynhronous Networking using Carrier Sense Multiple Access (CSMA/ CD) over CoAxial, twister pair copper and optical fiber medium. Speed range varied from 10Mbps to 10Gbps

802.4 Token Bus Disbanded

802.5 Token Ring Disbanded

802.6 Distributed Supported

Queue

Dual Bus(DQDB)

802.7 Broadband, LAN Disbanded

802.8 FiberOptics Practic Disbanded

802.9 Integrated Service, LAN Disbanded

802.10 Inter-portable Disbanded

802.11 WIFI Wireless Lan Media Access Control and Physical Layer Specification. 802.11a, 802.11b, 802.11g etc are ammend to the original 802.11 standards

802.11a - It use Oritigonal Frequency Division Multiplexing(OFDM). it enchanced data speed to 54 Mbps.

802.11b - It Enchanced the 802.11a that added Higher Data Rate or more to the direct

sequence spread spectrum(DSSS) already defined in the original 802.11 Standard. Boosted data speed to 11 Mbps. 22 Mhz Bandwidth yields 3 Non overlapping channels in the frequency in the range of 2.400Ghz to 2.4835 Ghz.

802.11d - It enchancement to 802.11a and 802.11b that allows for global roaming

802.11e - Echancement ot 802.11 that includes Quality of Service(QoS) feature. Also Fecilates

Voice and Video Transmission.

802.11g - It Extend Maximum Data rate of Wireless LAN Devices that in 2.4 Ghz Band, in a

fashion permits inter Operation with 802.11b devices. It use OFDM Modulation Operated at 54 Mbps

Wireless LAN and IEEE 802.11 Architecture

Wireless LAN are Those local area networks that use High Frequency Radiowaves instead of cables for connecting

the device in LAN.

User Connected by WLAN can move around withing the area of network coverage, Most WLAN's Are based upon

the standard IEEE 802.11 or WIFI.

Architecture

The Components of an IEEE 802.11 Architecture are as follows:

1. Station(STA) - Station Comprise all devices and equipments that are connected to the wireless LAN. It is two

type

1. Wireless Access Point(WAP) - WAP simply access point are generally Wireless Route that form the base

station or access.

2. Clients - Clients are Workstation (Laptop/desktop).

2. Basic Service Set(BSS) - BSS is a group of stations communicating at Physical Layer level. BSS can be of two

category depending upon mode of operation:

1. Infrastructure BSS: Here The Device Communicate with other Device through Access Point.

2. Independed BSS: Here the Device Communicate in Peer to Peer Basis in an AdHoc Manner.

3. Extended Service Set(ESS) - It is a set of all connected BSS.

4. Distribution System - It connects Access points in ESS.

Advantages of Wireless LAN

1. The Provide Clutter Free Homes, Office and other Network Places.

2. The LAN are Scalable in nature.

3. The System is Portable with the network coverage and Access to the network is not bounded to the length

of the cable.

4. Installation Setup is much easier then Wired LAN.

5. The Equipment and setup Cost are reduced.

Disadvantages of Wireless LAN

1. Since radiowaves are used for communication, the Singals are noisier with more interfarence from nearby

Systems.

2. Greater Care is needed for encypting information.

3. WLAN are slower than Wired Lan.

************************************************************************************************************

************************************************************************************************

UNIT-I II III MARKS: 5

1. WHAT ARE THE APPLICATIONS IN SATELLITES?

2. DEFINE MOBILE COMPUTING AND THE ADVANTAGES OF MOBILE COMPUTING

3. DISTINGUISH BETWEEN MOBILE COMPUTING AND WIRELESS NETWORKING

4. DEFINE MOBILITY AND WHAT ARE THE DIFFERENT KINDS OF MOBILITY?

5. DESCRIBE DIFFERENT KINDS OF OBSTACLES IN MOBILE COMMUNICATION

6. DESCRIBE WITH COMPARISON 1G AND 2G CELLULAR NETWORK

7. WHAT IS BLUETOOTH?

8. LIST FEW FUNCTIONS OF BLUETOOTH?

9. DIFFERENTIATE BETWEEN PICONET AND SCATTERNET IN BLUETOOTH TECHNOLOGY.

10. LIST THE APPLICATION OF MOBILE COMPUTING

11. POINT OUT THE ISSUES OF WIRELESS MAC PROTOCOL

12. ILLUSTRATE OR DESCRIBE THE STRUCTURE OF MOBILE COMPUTING APPLICATION

13. DIFFERENCE BETWEEN TRADITIONAL IP AND MOBILE IP

14. FORMULATE A PLAN TO CREATE MOBILE IP ALONG WITH BASIC REQUIREMENTS

15. STATE THE FUNCTION OF SMTP AND SNMP PROTOCOL

16. DESCRIBE THE STRUCTURE OF TCP SEGMENT

17. DEFINE ADAPTIVE TRANSMISSION CONTROL MECHANISM

18. DESCRIBE ABOUT SNOOPING TCP WITH SUITABLE EXAMPLE

19. WHAT DO YOU MEAN BY PULLING?

20. DESCRIBE THE ROLE OF A MAC PROTOCOL AND CLASSIFY THE TYPES OF MAC PROTOCOL

21. WHAT IS KNOWN AS HANDOFFS.

22. WHAT ARE THE TYPES OF HANDOFFS?

23. ANALYZE THE OBJECTIVES OF MAC PROTOCOL

24. WHAT ARE THE SEVERAL VERSION IN CSMA? WHAT IS MEANT BY NON PERSISTENT CSMA?

25. LIST THE SERVICES OF GSM

26. DEFINE GPRS SYSTEM

27. WHAT ARE THE SUBSYSTEM IN GSM SYSTEM? WHAT IS THE INFORMATION IN SIM?

28. CLASSIFY THE CATEGORIES OF GPRS SERVICES. "GPRS IS ADVANTAGEOUS THAN GSM" JUSTIFY THE STATEMENT.

29. WHAT ARE THE MAIN ELEMENTS OF UMTS?

30. HOW UMTS NETWORKS ARE DIFFERENT FROM 2G NETWORK?

31. DEFINE CDMA. WHAT ARE THE SUBSYSTEM IN GSM SYSTEM.

32. WHAT ARE THE DIFFERENT KINDS OF MOBILITY? WHAT IS MOBILITY MANAGEMENT?

33. WHAT ARE THE TYPES OF SPREAD SPECTRUM AND DIFFERENTIATE THEM.

34.

************************************************************************************************************

************************************************************************************************

MANET PROTOCOL

3 TYPES

PEOACTIVE : DSDV AND GSR

REACTIVE: DSR, AODV

HYBRID: ZRP

PROACTIVE: TRADITIONAL DISTRIBUTED SHORTEST PATH

REACTIVE: ON DEMAND (WHEN DOING, GOSSIPING PROTOCOL)

HYBRID:

PROACTIVE ROUTING PROTOCOL:

These are also known as table driven routing protocol. Each mobile node maintains a separate routing table which contain the information of the root to all the possible destination mobile nodes. since the topology in the mobile adhoc network is dynamic this routing tables are updated periodically as and when the network topology changes.

Example : DSDV

DSDV: it is a proactive or table driven routing protocol. It is actually extend the distance vector routing protocol of the wired protocol as the name suggested. It is based on Bellman ford routing algorithm.

Example : Global state routing

GSR: It is a proactive or table driven routing protocol. It is actually extend the link state routing of the wired network. It is based on the Dijkstra routing algorithm.

REACTIVE ROUTING PROTOCOL:

These are also known as On-demand routing protocol. In this type of routing the root is discovered only when it is required or needed. The process of root discovery occurs by flooding the root request packet through out the mobile network. It consist of two major phases mainly one is root discovery and root maintenance.

Example : Dynamic source routing protocol (DSRP)

DSDV:

application advantage: voice over ip, video conferencing,

dos >300
up >75mbps

https://www.artizanetworks.com/resources/tutorials/what_lte.html

3g project pl

tdm, fdm aksathe both

bandwidth 1.4mhz >20mhz

2004 comes

mobility 350kmph spread

duplexity half duplex, full all use 1 a time,

modulation QPSK

5-30km strong signal

Technical advantage : High throughput, high datarate, hithroughput, both uplink and downlink. low latency, suprior enduser experience, simless connection to exesting gsm, simple architecture ( low op).

CAPEX, OPEX => Cloud use

capex => Iaas using all equipment provided by user. Capital cost provide and may be sent to amazon.

opex => Run and power and cooling cost, paid by user. no mater in stroage capacity. and maintenace cost only required.

************************************************************************

LTE ARCHITECTURE

LTE is build up with the following 3 main component.

no. 1. EU : User Equipment UE:

no. 2.: E-UTRAN Envolve Umtas terisrerial radio access network :

no. 3. : EPC The Envolved Package Core

no. 1. EU >>

The Envolved Packet code communicate with packet data network in the outside world. Such as Internet, Private Corporate network, The IP multimedia subsystem.

The interface between the different parts of the system are denoted UU, S1 and SGI as above figure.

The internal architecture of the user equipement for LTE is identical to the one used by UMTS and GSM which is actually a mobile equipment ME. The mobile equipment comprised of the following important module.

a) MOBILE TERMINATION (MT): This handle all the communication function.

b) TERMINAL EQUIPMENT(TE): This terminates the data stream

C) UNIVERSAL INTEGRATED CIRCUIT CARD (UICC): This is also known as SIM card for the LTE equipment.

D) UNIVERSAL SUBSCRIBER IDENTITY MODULE (USIM): A USIM stored user specific data very similar to 3G SIM card. This keeps information about the user phone number, home network, Network security keys etc.
*

no. 2.: E-UTRAN>>

The E-UTRAN handles the radio communication between the mobile and even packet core, It involve base station called E and B. Each eNB that control the mobile in one or more cell. The base station that is communicating with a mobile is known as serving eNB.

LTE mobile communicates with just one base station and one cell at a time and there are following two main functions supported by eNB.

a) THE eNB sends and receive radio transmission to all the mobile using Analog and Digital signal processing function of the LTE AR interface.

b) The eNB control the low level operation of all its mobile by sending them signaling message, such as handover command. Each eNB connects with EPC by means of the S1 interface and it can also be connected to near by base station by S2 interface wich is mainly use for signaling and packet forwarding during handover.

A home eNB(HeNB) is a base station that has been purchased by a user to provide FRAME to cell coverage with in the home A Home eNB belongs to closed subscriber group cand can only be access by mobiles with a USIN that also belongs to closed subscriber group.

no. 3. : EPC THE ENVOLVED PACKET CORE: >>

Below is a brief description of each component shown in the above architecture.

HSS HOME SUBSCRIBER SERVER: The HSS component has been carried forward UMTS and GSM and is a central database that contains information about all the netwrok operators subscriber.

The packet data network PDN gateway (P-GW) communicates with the outside world using SGI interface. Each packet data network is identify be an access point name (APN). The PDN gateway has the same role as the GPR support node (GGSN) and service GPRS support node *

with UMTS and GSM.

The serving gateway acts as a router and forward data between the base station and PDN gateway.

The mobility management LTE(MME) control the high level operation of the mobile by signaling message and home subsriber server.

The policy control and the charging rule function (PCRF) is a component which is not shown in the above diagram but it is responsible for polict control decisoon making, as well as for the controling the flow based charging functionality in the policy control enforcement function (PCEF) which recites in the P-GW.

The interface between the serving and PDN gateway is known as S5, and S8. This has to be lightly different implementation mainly S5 is the two devices are in the same network and S8 if they are in different network.

Functional split between the E-UTRAN and the EPC

2g / 3g vs LTE

GERAN and UTRAN | E-UTRAN

SGSN or TDSM - FA | S-GW

GGSN or PDSM HA | PDN-GW

HLR or AAA | HSS

VLR | MME

SS7-MAP/ ANSI-41/RADIUS | DIAMETER,

GDP v0, v1 | GDP v2

**********************************************

LTE PROTOCOL STACK LAYERS

PHYSICAL LAYER:

Physical layer carry all information from the maC transport channel over the air interface. Take care of the link adaption, power control, salses search (For initial synchronization and handover purpose) and other measurement (Inside the LTE system and between the system) for the RRC layer.

MAC LAYER:

Mac layer is responsible for mapping between logical channel and transport channel, multiplexing of MAC SDU from one or different logical channel onto Transport block(TB) to be delivered to the physical layer on transport channel. Demultiplexing of MAC SDU from one or different logical channel from transport block (TB) delivered from the physical layer on Transport channel. Scheduling information reporting, Error correction through HARQ, priority handling between user equipement(UE) by means of dynamic scheduling, priority handling in logical channel of one user equipement, logical channel prioritized.

RAC (RADIO LINK CONTROL):

Tranport mode

Unacknowledgement mode

Aclnowledge mode

RAC layer is responsible for transfer of Upper later PDU, error correction through ARQ (only for AM data transfer) segmentation and reassembly of RLC and HDU (only for UM, AM data transfer). RAC is also responsible for resigmantation of RLC data. PDU (only for data transfer) ,

Reorder i**

duplicate detection (only for am and um data transfer). RLC HDU discard, RLC resablishment and protocol error detection.

RRC:

The main service and function of the RRC sublayer include broadcast of the system information related to the non-access stratum. (NAS), broadcast of system information related to the access stratum (AS) , paging , establishment, maintenance and release of an RRC connection between the USER equipement and E-UTRAN, security function including key management, establishment, configuration management, maintenance and release of point to point radio area.

Packet data concergence control (PDCC)

PDCC layer is responsible for header compression and decompression of IP data, Transfer of data, (user plane or control plane) maintenance of PDCP sequence number (SN), in sequence delivery of upper layer at Re-establishment , * duplicate elimination of lower layer is deal at re-establishment of lower layer of radio barrier . Map on RLC Ack. *

Typhering and deciphering of user plane of data and control plane of data integrity protection and integrity verification of control plane data, timer based scarred, duplicate discarding, Pdcp is used for again SRV and DRV. Mapped on EPPH and DCPH type of logical channel.

Non-Access Straum:

The Non-access straum *

Nass protocol support the mobility of the user equipment and the session management procedure established and maintain IP connectivity between the user equipement and a PDN gateway.

LTE OFDM technology:

To overcome the effect the miltipath fading problem available in MTs, LTE uses orthogonal division ,* gaining narrow band carrier of 180 kilohazds, of spreading one signal over the completer 5 MHZ carrier bandwidth. OFDM user a large number of narrow sub-carrier for multi-carrier transmission to carry data.

*/*

Advantages of OFDM:

1> The primary advantage *

making it possible to eliminate inter symbol interfaceance ISI

4> This mechanism also facilate the design of a single frequenct network SFN where serveral adjacent transmitter send the same signal simultaneously at the same frequency. As the signals from multiple distance transmitter may be combined constructively rather than interfering as good typically occur in a traditional signal carrier system.

Drawback of OFDM:

1> High peak to average ratio,

2> Sensitive to frequncy offset.

several different types of logical, transport and physical channel thich are distinguse by the kind of information they carry in which the information is processed.

LOGICAL CHANNEL:

It defines what type of information is transmitted over the Air. Example Traffic channel, control channel, System broadcast etc.

Data and signaling message are carried on logical channel between the RLC and MAC protocol.

TRANSPORT CHANNEL :-

It defines how is somthing transmitted over the air, what are the encoding, interliving option to transmit the data. Data and signaling messages are carried on transport channel between the MAC and physical layer.

It defines where is something transmitted over the air example first n symbol in DL frame.

Data and signaling * between the different level of physical layer.

*************************************************************

5G ARCHITECTURE

Architecture of 5g is highly advanced. Its network elements, various terminals are characteristucally updated to afford a new situation. Service provider can implement the advanced technology to adopt the value added services easily. However, Upgradibility is based upon radio technology that includes various significatnt feature such as ability of devices to identify their geographycal location as well as weathr, temparature etc. Radio technology acrs as a transiver that can catch and responce radio signal in its operating environment.

5G also advaned in terms of

1> HIGH INCREASED BIT_RATE :

2> LARGER DATA VOLUME PER UNIT AREA

3> LOW BATTERY CONSUMPTION

4> HIGH CAPACITY TO ALLOW MORE DEVICES CONNECTIVITY CONCURRENTLY.

5> LOWER COST OF INFRASTRUCTURE DEVELOPMENT.

The 5G model is entirely IP based model design for wireless and mobile network. The system comprising of main user terminal and then a number of independent autonomous radio access technology. Each of the radio technology is consider as the IP link for the outside internet world. The IP technology is design exclusively to ensure sufficient control data for appropriate routing IP packets related to a certain application connection ( Session between client application and server somewhere on the INternet). More over To make accessible routing of packets should be fixed in accordance with the given policy of the user that is shown in the above picture.

MASTER CORE TECHNOLOGY :

As shown in the figuare 5g master core is the main point for the other technology which have their own impact on existing wireless network. Its design facility master core to get operated into parallel multi mode including all IP network mode and 5g network mode. In this mode it control all network technologies of RN and different access network DAN, Since the technology is compatible and manages all the new deployment. It is more efficient, less complicated and more powerful.

THE MASTER CORE TECHNOLOGY

Any service mode can be opened under 5g new deployment mode as world combination service mode WCSM. WCSM is a wounderful feature for this technology For example if a processor writes on a whiteboard in a country, it can be displayed another whiteboard in any other part of the world besides conversation and video.

Application of 5g:

It will make unified global standard for all.

2> Network availabilty will be everywhere and will facilate people to use their computer and such kind of mobile devices anywhere anytime.

3> Because of the IPv6 technology visiting care of mobile IP address will be assign as per the connected network and geographical position.

4> Its cognitive radio technology will facilate different versions of radio technology to share the same specturm efficiency.

Important Advantage:

There are several advantages of 5g technology -

a) High resolution and large dimensional shipping.

b) Technology together to get all platform*

c) Technology to facilite lifetime supoervision code track

d) * which will support more than 60,000 connection.

e) Technological sound to support hetro*

Challenges:

a) Multiple service, Unlink other radio siganl services, 5g would have a huge tAsk oto fooffer services to heterogeneous netwrok technolgies devices operating in **

and data reach wireless service to fullfill to the high *

b) Infrastructure = Researchers are facing techlogical challenges of standarization of *

c) Communcation Navigation and sensing = These services are largly depend upon the availability of radio spectrum through which signals are transmitted though 5g technology has strong computational power to process the hugh volumn of data.coming from different and distinct sources but it needs larger infrastructure support.

d) Security and Privacy - This is one of the most imporatnt challenge that 5g needs ro ensure the protection of personal data. 5g will have to define the uncertainty related to security thread including trust, privacy, cybersecurity which are growing across the globe.

e) Cyber Law - Cyber crime and other fraud may also increase with the high speed 5g technology. Therefore, LEGISLATION of the cyber law is also an important issue. Which largly is governmental and policatical in nature. This is a basically national as well as International issue.

Search This Blog

MOBILE COMPUTING