Wireless review


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  • The Groups relate the speed and sophistication of the fax machine. The standards were developed by the ITU-T (International Telecommunications Union-Telecommunication Standardization Sector) in order that fax machines from different manufactures could communicate. Group 3 fax is the most common type of fax machine transmitting on A4 paper. The machine scanning format is digital and operates at rates between 9.6Kbps and 14.4Kbps. Asynchronous A method of transmitting data whereby each byte is clocked separately. One start bit is added to the beginning, and one or more stop bits to the end, of each character. Asynchronous transmission is the most rudimentary form of data communication, as the originating and recipient machines do not have to be in sync. It is commonly used for low speed transmission, as with a PC’s serial port. Synchronous Transmission Digital transmission in which the time interval between any two similar significant instants in the overall bit stream is always an integral number of unit intervals
  • USSD - offers an open cimmunication link for use between network and operatot and user for operator defined services operator barring restrictions of different services, vall types by the operator
  • The Mobile Station (MS) consists of the Mobile Equipment (ME) and the Subscriber Identity Module (SIM). · The Mobile Equipment (ME), commonly referred to as a terminal or handset, comes in two varieties: fixed and portable. A fixed MS is usually installed in a vehicle while portable MSs are normally carried by subscribers. Due to size limitations and power requirements, fixed MSs were originally predominant though this situation has changed dramatically in recent years as the portable MS is by now almost ubiquitous and even regarded as a fashion accessory. The ME is uniquely identified by its International Mobile Equipment Identity (IMEI) number, which is primarily used for security purposes. · A Subscriber Identity Module (SIM) is a smart card that is inserted into the ME to provide personal mobility. Each SIM card contains an International Mobile Subscriber Identity (IMSI) number that uniquely identifies the subscriber to the network thereby allowing access to subscribed services. To prevent unauthorised access, the SIM card can be protected using a Personal Identification Number (PIN). Only emergency calls can be made from a terminal without a SIM card. While the SIM card currently facilitates a number of services including the standard Short Message Service (SMS), advances in smart card technologies will ensure that the SIM card becomes a cornerstone for any new services deployed in the future.
  • The Base Station Subsystem is composed of two parts: the Base Transceiver Station (BTS) and the Base Station Controller (BSC). The Base Transceiver Station (BTS), or simply the Base Station, is the interface for the MS to the network. It handles all communications with the MS via the air interface (technically referred to as the Um interface in the GSM specifications). Essentially, the transmitting power of a BTS defines the cell size i.e. its coverage area. In large urban areas, the number of BTSs deployed is large so the corresponding cell size is small. In contrast, there is usually a far smaller number deployed in rural areas so the cell size can be quite large. The Base Station Controller (BSC) manages the radio resources for multiple BTSs, the number of which varies but could be up to several hundred. As well as the allocation and release of radio channels, the BSC is responsible for handover management when the MS roams into an area covered by another BSC. Similar to all other interfaces in GSM, the interface between the BSC and a BTS is standardised and is referred to as the Abis interface.
  • The Mobile Switching Centre (MSC) performs almost identical functions to that of a normal switching node in a fixed network. In addition, it provides the functionality needed to handle mobile subscribers including registration, authentication, location updating etc. Depending on size, a GSM network may contain a number of MSCs or just one. All GSM networks must connect to fixed networks at some point. This interconnection always takes place through an MSC in which case the MSC is called a Gateway MSC (GMSC). The interface between the MSC and a BSC is called the A interface
  • The Home Location Register (HLR) contains all the administrative information for each subscriber registered in the corresponding GSM network. This includes both the IMSI number and actual phone number as well as details of a subscriber’s permitted supplementary services e.g. call forwarding. The current location i.e. which Visitor Location Register (VLR) the subscriber is currently registered with, is also stored in the HLR as, without this, the MSC could not route any calls to the subscriber. Logically, there is one HLR for each GSM network, although it can be implemented as a distributed database.
  • Three new types of terminal have been defined in the GPRS standard: . Class A terminals, which support simultaneous circuit-switched and packet-switched traffic. For example, a subscriber can initiate or receive a voice call without interrupting data transmission or reception activity. . Class B terminals, which supports simultaneous connections to GSM and GPRS but cannot support both types of traffic at the same time. If a GPRS data call is in progress and an incoming voice call is received, the data call is suspended for the duration of the voice call. However, when the voice call is terminated, the GPRS data call will resume. . Class C terminals, which can handle either data or voice calls but can only be connected to either GSM or GPRS at any given time. The GPRS MS itself has two components: a Mobile Terminal (MT) which consists of a handset and SIM card, and a Terminal Equipment (TE) component which is typically a laptop or a Personal Digital Assistant (PDA).
  • The most important changes take place in the NSS with the introduction of two new nodes for the handling of packet data: . The Serving GPRS Support Node (SGSN) is responsible for handling packet data traffic in a geographic area. It monitors GPRS users, performs security procedures and handles access control. An SGSN may be regarded as doing for packet-switched data services what the MSC does for normal circuit-switched services. . The Gateway GPRS Support Node (GGSN) provides the internetworking functionality for external packet data networks e.g. the Internet. It can act as an access server and is responsible for routing incoming data traffic to the correct SGSN. To facilitate communication between different networks, it can translate between various different signalling protocols and data formats. The introduction of these nodes required that several new interfaces be defined to handle interactions between them and other NSS components. For example, the Gb interface is required between the BSC and the SGSN while queries are sent to the HLR by the SGSN over the Gr interface. To support GPRS subscribers, the HLR database must be upgraded to include details about which data services the subscriber is registered for.
  • While the implementation of GPRS will improve GSM network data capacities substantially, the individual subscriber experience may vary quite considerably. The theoretical maximum speed of 171.2 kb/s (eight timeslots by 21.4 kb/s) will never be achieved in a real network, as in practice, the available data rate will ultimately depend on the network configuration, which is defined by the network operator. Another factor that will influence the subscriber’s experience is what class of handset the operator supports. Even though GPRS specifies three classes, a particular network operator may only support one. Nevertheless, the situation will have improved considerably. Set-up time will be less than a second while data transfers will be less susceptible to errors and delays. The "always-on" nature of GPRS means that emails can be received without making an explicit connection. Also, the charging rate will favour the consumer who will be billed based on the amount of data transported by the network rather than on the amount of time connected to the network.
  • At present, GPRS is being rolled out in Europe whereas in Japan full 3G tests are being conducted with full deployment almost imminent. EDGE is currently being evaluated by various network operators with a view to deploying it as an interim step to 3G. However it is unlikely that EDGE will be deployed widely if operators believe that implementing a full 3G solution may be more economical. Recalling that the deployment of 3G requires new spectrum, it may be that those operators who fail to obtain 3G licences will use EDGE. Indeed this was one of the motivations for the development of EDGE originally.
  • Replacing the existing GSM air interface is the final and most important step in the evolution of GSM to UMTS i.e. 3G. Recall that one of the criteria for a system to be IMT2000 compliant is that it implements an air interface standard defined by the ITU. In the case of UMTS, the communication over the air interface, or UMTS Terrestrial Radio Access (UTRA) as it is technically known, is achieved using W-CDMA and TD-CDMA. The access parts of the network, called the UMTS Terrestrial Radio Access Network (UTRAN), are based on ATM and it is here that the major changes in upgrading will occur, which of course will also be reflected on the handsets (figure 4).
  • UMTS BSS The UMTS equivalent of the BSS, the Radio Network Subsystem (RNS) introduces two new network elements: Node B is responsible for radio transmission between subscribers. It may be regarded as fulfilling the same role as the BTS in standard GSM. The Radio Network Controller (RNC) supports a number of Node Bs and may be regarded as the UMTS BSC equivalent. A UTRAN will support a set of RNSs. Obviously, the introduction of new nodes into the networks means a corresponding increase in interface standards e.g. the Iur interface between two RNCs.
  • "2.5G customers" refer to those customers who have joined the service plans for 2.5G services (including GPRS and IS-95B services) or used the 2.5G services
  • The importance of standardisation is crucial. For example, SMS has not experienced such a success in the US and Japan where the operators have competing technologies that are not interoperable. MMS is THE ONLY standardised messaging technology for 3G and that's what guarantees its success as an evolution from the SMS success. MMS is standardised by 3GPP and the WAP forum. SMS has acted as a bridge between voice and data traffic. It has changed the users' perception about the mobile phone: they are beginning to see it as a communication and information media rather than just a telephone. --- Given the converging market and technology space, what is the right way to develop successful new services? To identify and build on a natural application migration path... The first crucial step in MMS market development is getting consumers accustomed to using their mobile phones for purposes other than voice communication, i.e. making current SMS applications more commonly used. Focusing on creating awareness and acceptance for the concept of SMS as well as on educating the market on how specific services work. SMS messaging = mobile email =' Gmail' => discretion, efficiency, fun; anytime, anywhere. MMS = 'enhanced SMS', with full content versatility => fun, sharing, rational utility. Nokia's migration path in multimedia messaging builds on the well-established SMS paradigm by adding new functionality and new content types in consumer-understandable steps. This will reduce the barriers for MMS adoption, leading to rapid take-up and high penetration, paving the way towards personal mobile multimedia. Picture Messaging: Combines the ease of use of SMS with the enjoyment of expressing oneself with pictures. Spec is now available at www.forum.nokia.com - no longer proprietary. Digital image input: Enables the electronic postcard based on instant photographs and text. Multimedia Message Service (MMS) and Mobile Multimedia: A complete end-to-end solution for person-to-person mobile messaging, from terminal to terminal, terminal to internet, internet to terminal. With full content versatility, including images, audio, video, data, text. Delivers a location independent, total communication experience - combined with ease of use that is a simple, logical extension of SMS and Picture Messaging.
  • And we believe the WAP content will continue to expand, much in a similar fashion as the popularity of text messaging and SMS based services has exploded. The exponential growth typically starts when the 20-40% mobile phone penetration window has been reached, as is evident from these figures from various European markets.
  • Just some of the phones available now or soon Samsung SGH-S100 (not T100, which is available now) Siemens SX45 (coming now) Nokia 7210 (expected mid October) Ericsson P800 (unknown, should be out now) Motorola A388 (unknown when available) Nokia 3650 (Unknown, Symbian Series 60) Nokia 3410 (Price: 1500 NOK, can get it for NOK 90 with subscription) Siemens M50 Siemens (6 phones) C55, MT50, SL42, M50, SL45i, SX45 Nokia (7 phones) 3410 (On picture), 3510i (Color Series 30!), 3650 (On picture – Series 60), 6310i (World phone), 6610 (Series 40), 7210 (On picture – Series 40), 9210 + 9210i Communicator (Series 80) Samsung SGH-S100 Motorola (8 phones) A820 (?) (September), Accompli 008, Accompli 009, A388, T280i, T720, V60i, V66i Sony Ericsson (2 phones) P800, Z700
  • WiFi (Wireless Fidelity) [HL02] is the popular name for the WLANs based on the IEEE 802.11b standard [ICS99]. As well as being deployed in businesses and homes, WiFi is also being deployed in open areas to create what are termed "hotspots". It is hoped within the industry that WiFi will bring broadband Internet access to the general population. WiFi has a range of about 50 meters and supports a theoretical throughput of 11Mb/s. In practice, 7 Mb/s is a more realistic figure. WiFi operates in the unlicensed 2.4 GHz spectrum. Unfortunately, thick walls can reduce both the range and the throughput considerably. However, by using high gain external antennae, and under line-of-sight conditions, WiFi offers a very attractive alternative to leased lines or conventional microwave systems. A newer version of the protocol – 801.11a offer throughputs of up to 54Mb/s and operate in the 5GHz band. However, it may be less useful in offices and buildings as walls absorb the higher frequencies more than the 2.4GHz signals of 802.11b.
  • Two problems continue to affect WiFi in an adverse manner. WiFi is essentially an insecure system principally because it was not designed with robust security as a priority. However, this issue continues to receive urgent attention within the WiFi community. The second problem concerns interference. As it operates in unlicensed spectrum, it could find itself competing with other products. For example, a microwave oven operating in the neighbourhood and at a similar frequency would cause problems, as could another business’s WLAN. As WiFi installations are relatively rare, such issues are not of concern today. However, should WiFi be deployed as its advocates wish, such issues will become increasingly important and the need for solutions more urgent.
  • Bluetooth [URL15] is a universal radio interface that enables portable electronic devices connect and communicate wirelessly via short-range ad-hoc networks [Haa98]. One of the objectives of Bluetooth is to eliminate the need for the cabling and connectors that plagues modern computing systems. For example, if somebody received an email on their Bluetooth-enabled mobile phone and a hard copy was required, they could approach a Bluetooth-enabled printer and print the message directly without resorting to installing device drivers or connecting via a LAN etc. To enable visions like this, Ericsson, Nokia, Toshiba, IBM and Intel formed the Bluetooth SIG in 1998 with the specific objective of defining a suitable specification. This specification would then be used by various companies to implement their own products thereby ensuring interoperability.
  • From a technical perspective, Bluetooth operates in the international 2.4 GHz frequency band with a gross data rate of 1Mbit/s. The nominal range of a Bluetooth device is 10 meters. Two or more Bluetooth devices can form a piconet. To regulate traffic between devices, one must become a master – usually the device that establishes the piconet. The others are termed slaves. A group of piconets is termed a scatternet. A device may be a member of a number of piconets at the same time. One of the advantages of the piconet-scatternet architecture is that it can increase both the range and the data throughput of individual devices.
  • One of the primary objectives of satellite telephony is to extend access to people in remote areas where terrestrial fixed line and cellular services do not exist. By regarding a satellite as a base station in orbit, the principles behind satellite telephony are very similar to those underpinning cellular communications. However, subscribers to a satellite service enjoy global roaming, a feature not yet available to their terrestrial cellular counterparts. Satellite telephony systems can be classified according to the height of their orbits (table 2). The success of satellite based telephony systems has been varied. While the technology is proven, nevertheless, there have been some high profile spectacular commercial failures. Both Iridium and ICO were rescued from bankruptcy. Naturally, the reasons given vary. However it is thought that events on the ground, namely the success of 2G networks contributed. For example, Iridium was conceived in the early 1990s, but by the time it was deployed (almost a decade later), it could not compete competitively with GSM. However, its revised business model is geared towards serving industrial and institutional subscribers rather than the personal communications market.
  • Wireless review

    1. 1. An Overview of Wireless Data Communications Wide Area Cellular Services Wireless LANs Satellite Integrated Wireless Services Richard Perlman Lucent Technologies [email_address]
    2. 2. Wide Area Cellular Services
    3. 3. The Cellular Principle <ul><li>Relies on the concept of concurrency </li></ul><ul><ul><ul><li>delivered through channel reuse i.e. reusing channels in different cells </li></ul></ul></ul><ul><li>Total coverage area is divided into cells </li></ul><ul><ul><ul><li>only a subset of channels available in each cell </li></ul></ul></ul><ul><li>All channels partitioned into sets </li></ul><ul><ul><ul><li>sets assigned to cells </li></ul></ul></ul><ul><ul><li>Rule: assign the same set to two cells that are sufficient geographically distant so that interference is small </li></ul></ul><ul><ul><li>Net result: increased capacity! </li></ul></ul>
    4. 4. Advantages of Cellular Networks <ul><li>More capacity due to spectral reuse </li></ul><ul><li>Lower transmission power due to smaller transmitter/receiver distances </li></ul><ul><li>More robust system as Base Station problem only effects the immediate cell </li></ul><ul><li>More predictable propagation environment due to shorter distances </li></ul>
    5. 5. Disadvantages of Cellular Networks <ul><li>Need for more infrastructure </li></ul><ul><li>Need for fixed network to connect Base Stations </li></ul><ul><li>Some residual interference from co-channel cells </li></ul><ul><li>Handover procedure required </li></ul>
    6. 6. GSM Services - Phase 1
    7. 7. GSM Services - Phase 2
    8. 8. GSM Services - Phase 2+ <ul><li>Primarily concerned with the improvement of Bearer (data!) services </li></ul><ul><ul><li>Full data rate @ 14.4 kb/s </li></ul></ul><ul><ul><li>High Speed Circuit Switched Data (HSCSD) </li></ul></ul><ul><ul><li>General Packet Radio Service GPRD) </li></ul></ul><ul><li>Some additional supplementary services also specified </li></ul>
    9. 10. Architecture of a GSM Network
    10. 11. Mobile Station (MS) <ul><li>Mobile Equipment </li></ul><ul><ul><ul><ul><li>Fixed </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Portable </li></ul></ul></ul></ul><ul><ul><ul><li>International Mobile Equipment Identity (IMEI) number </li></ul></ul></ul><ul><li>Subscriber Identity Module (SIM) </li></ul><ul><ul><ul><li>Personal Identification Number (PIN) </li></ul></ul></ul><ul><ul><ul><li>International Mobile Subscriber Identity (IMSI) number </li></ul></ul></ul><ul><ul><ul><li>Enables access to subscribed services </li></ul></ul></ul><ul><ul><ul><li>Smart card </li></ul></ul></ul>
    11. 12. Base Transceiver Station - BTS <ul><ul><li>Usually referred to as the Base Station </li></ul></ul><ul><ul><li>Provides the interface to the network for the MS </li></ul></ul><ul><ul><li>Handles all communications with the MS </li></ul></ul><ul><ul><li>Less “intelligent” than analogue equivalent </li></ul></ul><ul><ul><ul><li>cheaper than analogue systems </li></ul></ul></ul><ul><ul><ul><li>bypass analogue in less wealthy countries </li></ul></ul></ul><ul><ul><li>“intelligence” now deployed on MS </li></ul></ul><ul><ul><ul><li>for example, when to perform a handover </li></ul></ul></ul><ul><ul><li>Transmitting power determines cell size </li></ul></ul>
    12. 13. Base Station Controller - BSC <ul><ul><li>Controls Base Stations </li></ul></ul><ul><ul><ul><li>up to several hundred depending on manufacturer </li></ul></ul></ul><ul><ul><li>Manages radio channels </li></ul></ul><ul><ul><ul><li>allocation and release </li></ul></ul></ul><ul><ul><li>Coordinates Handover </li></ul></ul><ul><ul><li>Physical location may vary </li></ul></ul><ul><ul><li>Abis interface </li></ul></ul><ul><ul><ul><li>between BSC and BTS </li></ul></ul></ul>
    13. 14. Mobile Switching Centre (MSC) <ul><ul><li>Performs all switching/exchange functions </li></ul></ul><ul><ul><li>Handles </li></ul></ul><ul><ul><ul><ul><li>registration </li></ul></ul></ul></ul><ul><ul><ul><ul><li>authentication </li></ul></ul></ul></ul><ul><ul><ul><ul><li>location updating </li></ul></ul></ul></ul><ul><ul><li>A GSM network must have at least one MSC </li></ul></ul><ul><ul><li>May connect to other networks </li></ul></ul><ul><ul><ul><li>Gateway MSC (GMSC) </li></ul></ul></ul>
    14. 15. Home Location Register (HLR) <ul><ul><li>Administrative information for all subscribers </li></ul></ul><ul><ul><ul><li>IMSI number </li></ul></ul></ul><ul><ul><ul><li>actual phone number </li></ul></ul></ul><ul><ul><ul><li>permitted supplementary services </li></ul></ul></ul><ul><ul><ul><li>current location i.e. which VLR subscriber is currently registered with </li></ul></ul></ul><ul><ul><ul><li>parameters for authentication and ciphering </li></ul></ul></ul><ul><ul><li>One HLR per GSM PLMN </li></ul></ul>
    15. 16. Integrating GPRS
    16. 17. GPRS MS <ul><ul><li>Two Components </li></ul></ul><ul><ul><ul><ul><li>Mobile Terminal (MT) </li></ul></ul></ul></ul><ul><ul><ul><ul><li>SIM card </li></ul></ul></ul></ul><ul><ul><li>Three Classes of terminal </li></ul></ul><ul><ul><ul><ul><li>Class A - simultaneous circuit switched (GSM) and packet switched (GPRS) traffic </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Class B- supports both GSM and GPRS connections but not both at the same time. One call is suspended for the duration of the other </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Class C - handless both GPRS or GSM but can only be connected to one at the same time. </li></ul></ul></ul></ul>
    17. 18. GPRS NSS <ul><li>Two new nodes introduced for packet data </li></ul><ul><ul><li>Serving GPRS Support Node (SGSN) </li></ul></ul><ul><ul><ul><li>handles all packet data for the appropriate geographic area </li></ul></ul></ul><ul><ul><ul><ul><li>monitors GPRS users </li></ul></ul></ul></ul><ul><ul><ul><ul><li>handles security and access control </li></ul></ul></ul></ul><ul><ul><ul><ul><li>may be regarded as the packet switched equivalent of the circuit-switched MSC </li></ul></ul></ul></ul><ul><ul><li>Gateway GPRS Support Node (GGSN) </li></ul></ul><ul><ul><ul><ul><li>internetworking functionality </li></ul></ul></ul></ul><ul><ul><ul><ul><li>routes incoming data to correct SGSN </li></ul></ul></ul></ul><ul><ul><ul><ul><li>translates between different protocols and formats </li></ul></ul></ul></ul><ul><ul><li>Details of data services added to HLR </li></ul></ul>
    18. 19. GPRS - Summary <ul><li>Data capacity increased considerably </li></ul><ul><li>Depending on configuration </li></ul><ul><ul><ul><li>@ 14.4 kb/s per channel, 115.2 kb/s achieved </li></ul></ul></ul><ul><ul><ul><li>@ 21.4 kb/s per channel, 171.2 kb/s achieved </li></ul></ul></ul><ul><li>BUT up to 8 users per channel! </li></ul><ul><li>Minimum set-up time </li></ul><ul><li>“always-on” connection </li></ul><ul><li>Charging determined by actual data not time </li></ul>
    19. 20. Integrating EDGE <ul><li>Minimum changes to the existing network </li></ul><ul><li>New Modulation scheme </li></ul><ul><ul><li>8 phase shift keying (8PSK) </li></ul></ul><ul><ul><li>3 bits of information per signal pulse </li></ul></ul><ul><ul><li>data rates increased by a factor of three </li></ul></ul>
    20. 21. EDGE - NSS <ul><li>Minimum impact on the core network </li></ul><ul><li>SGSN & GGSN practically independent of data rates </li></ul><ul><li>Some minor software upgrades </li></ul>
    21. 22. 3G - UMTS
    22. 23. UMTS - MS <ul><li>User Equipment </li></ul><ul><ul><li>Mobile Equipment </li></ul></ul><ul><ul><li>UMTS SIM (USIM) </li></ul></ul><ul><ul><li>Air interface </li></ul></ul><ul><ul><ul><li>UMTS Terrestrial Radio Access (UTRA) </li></ul></ul></ul><ul><ul><ul><ul><li>W-CDMA </li></ul></ul></ul></ul><ul><ul><ul><ul><li>TD-CDMA </li></ul></ul></ul></ul>
    23. 24. UMTS BSS <ul><li>Radio Network Subsystem </li></ul><ul><li>Two new network elements </li></ul><ul><ul><li>Node B </li></ul></ul><ul><ul><ul><li>equivalent of a BTS </li></ul></ul></ul><ul><ul><li>Radio Network Controller </li></ul></ul><ul><ul><ul><li>supports a number of Node Bs </li></ul></ul></ul><ul><ul><ul><li>equivalent of a BSC </li></ul></ul></ul><ul><li>Obviously, UMTS has major implications for the BSS </li></ul>
    24. 25. CDMA BASICS <ul><li>CDMA (Code Division Multiple Access) splits calls into fragments and send them over different frequencies simultaneously </li></ul><ul><li>The use of multiple frequencies gives CDMA effective protection against interference and lost calls </li></ul><ul><li>CDMA supports true packet switching and does not use time slots, therefore is more bandwidth efficient than TDMA -- also a more direct path to 3G </li></ul><ul><li>Current CDMA penetration in the world market is about 27% </li></ul>
    25. 26. 3G CDMA Architecture <ul><li>CDMA2000-1xEVDO System Architecture (Basic) </li></ul><ul><li>BTS: Base Station, which creates a single cell </li></ul><ul><li>BSC: Base Station Controller, which controls roaming and channel allocations amongst various BSTs and is also referred to as a Radio Network Controller (RNC). </li></ul><ul><li>MSC: Mobile Switching Center, which performs the telephony switching functions and is usually connected to an SS7 network. </li></ul><ul><li>PDSN: Packet Data Serving Node, maintains IP communications between all MNs and the Packet Data Network (PDN), which in this diagram is the Internet. </li></ul><ul><li>Note: For simplicity, only the CDMA2000 architecture will be reviewed for this presentation </li></ul><ul><li>SOURCE: CDMA Development Group (CDG) 3G CDMA Architecture </li></ul>
    26. 27. BTW, the US didn’t pick ANY 2G standard--with predictable results <ul><li>The US allowed adoption of multiple wireless network technologies, including: </li></ul><ul><ul><li>IS-95 CDMA (cdmaOne) </li></ul></ul><ul><ul><li>IS-136 TDMA </li></ul></ul><ul><ul><li>iDEN (Nextel) </li></ul></ul><ul><ul><li>GSM </li></ul></ul><ul><li>Unlike Europe and Japan, the US now lacks a dominant 2G standard – carriers and subscribers are using CDMA, TDMA, iDen, and GSM </li></ul>
    27. 28. Why do carriers want to move to 3G? <ul><li>Faster speeds--able to handle more calls </li></ul><ul><li>Efficiencies in data handling </li></ul><ul><ul><li>Integration with the Internet technology </li></ul></ul><ul><li>More capable, multi-media handsets and devices </li></ul><ul><li>Global interoperability and roaming* </li></ul><ul><li>Advanced services and more profitable revenue opportunities** </li></ul>
    28. 29. Some Urgent 3G Drivers <ul><li>Need to increase wireless data revenues and ARPU as voice prices decline </li></ul><ul><li>Staggering investment already made in preparing for 3G upgrades </li></ul><ul><li>Pressure by device makers and governments </li></ul><ul><ul><li>3G License clock ticking in Europe </li></ul></ul><ul><li>Dramatic success stories: </li></ul><ul><ul><li>Korea, Japan markets are embracing 3G </li></ul></ul><ul><li>Fear of falling even further behind </li></ul><ul><ul><li>Competition from WiFi as the high-speed alternative </li></ul></ul>
    29. 30. Comparative Network Speeds Source : ITU.
    30. 31. 3G Systems Overview 3G Migration SOURCE: CDMA Development Group (CDG) CDG Migration Diagram
    31. 32. Mobility Overview <ul><li>Future mobility will be provided with higher data rates and Ubiquitous access </li></ul><ul><ul><li>This implies the need for seamless wide area and office coverage </li></ul></ul><ul><ul><li>Future remote access techniques will mirror existing to protect current investments </li></ul></ul><ul><li>Higher data rates and better coverage will be realized using disparate types of Wireless Technologies </li></ul><ul><ul><li>Mobility across disparate networks is a significant change to the paradigm of current mobile networks. </li></ul></ul><ul><ul><li>Mobility is attributed to L2 and L1 abstraction through use of IP (Mobile IP). </li></ul></ul>Data Rates and Ranges of Wireless Technologies SOURCE: ITU
    32. 33. 3rd Generation Wireless Vision <ul><li>Extends current data applications & devices </li></ul><ul><li>Enables breakthrough data services </li></ul>Web Browsing E-mail E-Commerce Telemetry Vertical Solutions Vehicle Location Messaging Full Web browsing E-mail w/ Attachments Richer E-Commerce Multimedia Messaging Streaming Audio & Video Online Games Video Telephony Music Download 2nd Generation 3rd Generation 9.6 Kbps 28.8 Kbps 384 Kbps
    33. 34. Standards Evolution to 3G Worldwide Japan Europe/Parts of Asia Americas/Parts of Asia Instead of solving the 2G network differences via 3G, we will continue to have W-CDMA and cdma2000 as separate networks. Both will be “optional implementation modes” in one 3G standard specification. Basic 3G phones will support one or the other. “Global phones” will be able to roam from one to the other. cdma2000 1st Gen TACS NMT/TACS/Other AMPS 2nd Gen PDC GSM TDMA CDMA 3rd Gen EDGE cdma2000 W-CDMA/UMTS
    34. 35. Application Platforms For Cellular Networks <ul><li>WAP : discredited in first outing, but still alive and well as a backend mobile server standard </li></ul><ul><li>SMS : proven worldwide but just emerging in US; limited to plain text messaging </li></ul><ul><li>MMS : standard behind the exchange of pictures from camera phones; also for many audio and graphic formats </li></ul><ul><li>iMode : proven in Japan; export still in doubt </li></ul><ul><li>J2ME (Java for mobile): large developer following and handset deployment; confused business models </li></ul><ul><li>BREW : CDMA app platform: big in a few areas; clearer business and distribution model </li></ul>
    35. 36. Overview of WAP <ul><li>WAP is an acronym for Wireless Application Protocol </li></ul><ul><li>A WAP-enabled phone acts like a miniature browser – with obvious limitations on graphical display </li></ul><ul><li>WAP content is marked up in WML – Wireless Markup Language </li></ul><ul><li>Small client-side applications can be written in WMLScript (like JavaScript) </li></ul><ul><li>Images are crude and delivered in wbmp format </li></ul>
    36. 37. WAP Architecture <ul><li>WAP combines handset and server functionality: </li></ul><ul><ul><li>The mobile device has embedded browser </li></ul></ul><ul><ul><li>software </li></ul></ul><ul><ul><li>This browser connects to a WAP gateway and makes a request for information from a WAP- enabled web server </li></ul></ul><ul><ul><li>The content for wireless devices can be stored on any web server on the Internet, but the content must be formatted for the mobile device using WML </li></ul></ul>
    37. 38. Early WAP Was Over-Sold <ul><li>Wireless Internet Browsing conveyed WWW on the phone—not what subscribers experienced </li></ul><ul><li>Expected WAP to quickly become the “killer application” builder for mobile commerce </li></ul><ul><ul><li>Hundreds of new companies and thousands of WAP developers quickly went out of business instead </li></ul></ul><ul><li>Currently WAP is valued as infrastructure for delivering content and messaging to phones </li></ul><ul><ul><li>Re-emerging as Internet enabled phone client </li></ul></ul>
    38. 39. Evolution of messaging Rich Call Browsing Messaging Versatility of Content and User Benefits Time Text SMS Text & Graphics Picture Messaging Digital image input Multimedia Message Service New content types Mobile Multimedia
    39. 40. SMS <ul><li>SMS=Short Message Service=Current Worldwide “Killer Application” </li></ul><ul><li>A basic text messaging service for sending messages up to 160 characters to mobile phones </li></ul><ul><li>Runs on separate channel from voice traffic-much cheaper for operators to carry text messages (started out as free service in many countries) </li></ul><ul><li>Overwhelming user uptake in Europe and A/P --billions of messages sent each month; very profitable for carriers </li></ul>
    40. 41. SMS growth in Europe 0 10 20 30 40 50 60 0% 10% 20% 30% 40% 50% 60% 70% 80% Mobile Penetration SMSs/subs/month Finland Norway Germany Italy Portugal Greece UK France Sweden Spain
    41. 42. i-Mode <ul><li>In 1999 Japanese wireless operator NTT DoCoMo decided to launch its own specially developed application environment for subscribers and to open its billing system to application providers </li></ul><ul><li>DoCoMo developed a programming </li></ul><ul><li>language based on HTML (cHTML), set up the billing and distribution infrastructure and manufactured a new breed of application friendly handsets. </li></ul><ul><li>The service was branded as i-Mode </li></ul>
    42. 43. Importance of iMode Model <ul><li>First to value the content/app provider part of the business model--developers get the revenues for application usage (minus 9% for DoCoMo to handle billing) </li></ul><ul><li>Enormous popularity with very large range of titles and applications developed </li></ul><ul><li>Viewed as a potential model for Europe & US (investment in AT&T Wireless, launch with KPN) </li></ul>
    43. 44. J2ME and BREW Applications Why Run Locally on the Handset? <ul><li>Overcomes some of the issues with messaging applications </li></ul><ul><ul><li>No network/delivery delay in highly interactive apps like games </li></ul></ul><ul><ul><li>User not worried about cost of airtime or message delivery; one-time fee for downloading easier to present to the marketplace </li></ul></ul><ul><li>Can use processing power of device to add speed, graphics, and logic support for richer user experience </li></ul><ul><li>Simpler value chain for all players </li></ul>
    44. 45. New Phones Have MMS, WAP, Java (GSM) or BREW (CDMA) – 400 million plus in 2003
    45. 46. What is J2ME? <ul><li>Java 2 Micro Edition </li></ul><ul><ul><li>Optimized Java programming and execution for mobile devices </li></ul></ul><ul><ul><li>CLDC: Connected Limited Device Configuration </li></ul></ul><ul><ul><li>MIDP: Mobile Information Device Profile </li></ul></ul><ul><li>Creates a Virtual Machine that runs programs on the device </li></ul><ul><li>Makes it easy for large Java programming community to write mobile applications </li></ul><ul><li>Apps can be downloaded from carrier sites, Java portals, or directly from developers </li></ul><ul><li>No consistent business model to support revenue collection and marketplace management </li></ul><ul><ul><li>Nokia provides a marketplace at Tradepoint, but no testing and billing services </li></ul></ul>
    46. 47. What is BREW? <ul><li>Binary Runtime Environment for Wireless </li></ul><ul><ul><li>Also a sly poke at Java from its Qualcomm creators </li></ul></ul><ul><li>Like Java, BREW runs a virtual machine on the handset </li></ul><ul><ul><li>Allows user to download an application once from the wireless network and then interact with content without using air time </li></ul></ul><ul><ul><li>Supports graphics, etc. to make it suitable for games and interactive apps </li></ul></ul><ul><li>Applications written in C or C++ (or even Java) </li></ul><ul><li>Well-organized BREW business model created and maintained by Qualcomm </li></ul><ul><ul><li>Testing and “TrueBREW” certification for apps </li></ul></ul><ul><ul><li>For 20% of app revenue, Qualcomm manages marketplace </li></ul></ul>
    47. 48. Wireless LANs
    48. 49. Wireless LANs <ul><li>Wireless LAN networks, including 802.11 or Wi-Fi, are growing quickly for home and office applications </li></ul><ul><li>Unregulated frequency bands - Quality of Service not guaranteed, but speed, low cost, and ease of implementation are compelling </li></ul><ul><li>Very suitable for local data transmission and access outside operator networks - e.g. company internal solutions or home installations </li></ul><ul><li>Being endowed with roaming capabilities and voice enabled devices to compete directly with carrier-owned networks </li></ul>
    49. 50. Wi-Fi <ul><li>Wireless Fidelity (Wi-Fi) </li></ul><ul><li>IEEE 802.11b </li></ul><ul><li>50m range approximately </li></ul><ul><li>Data rates vary </li></ul><ul><ul><li>11 - 56 Mb/s in theory </li></ul></ul><ul><ul><ul><li>Higher with some proprietary extensions </li></ul></ul></ul><ul><ul><li>7 Mb/s is more realistic </li></ul></ul><ul><li>Walls can reduces range and throughput </li></ul><ul><li>Number of users can reduce data rates </li></ul>
    50. 51. <ul><li>WLANs are specified by IEEE 802.11 standards: </li></ul><ul><ul><ul><li>802.11a: 5.8 GHz OFDM technology supporting typical ranges of 100m and 54 Mbps data rates. </li></ul></ul></ul><ul><ul><ul><li>802.11b: 2.4 GHz DSSS technology supporting typical ranges of 100m and 11 Mbps data rates. </li></ul></ul></ul><ul><ul><ul><li>802.11g: 2.4 GHz OFDM & DSSS technology supporting typical ranges of 100m and 54 Mbps data rates. </li></ul></ul></ul><ul><ul><ul><li>802.11i: MAC layer security using AES, 802.1x, and SHA…Expected draft for 2004 </li></ul></ul></ul><ul><ul><ul><li>802.11e: QoS features in the air interface…Expected draft for 2004 </li></ul></ul></ul><ul><ul><ul><li>802.11f: Inter Access Point Protocol (IAPP) for seamless interoperable roaming…Expected draft for 2005 </li></ul></ul></ul>WLAN Overview RF & MAC Layer MAC Layer Features <ul><li>All 802.11 standards can be used for Point-to-Point or Point-to-Multi-Point configurations </li></ul>
    51. 52. Wi-Fi Problems <ul><li>Security </li></ul><ul><ul><li>Wi-Fi was not designed with robust security in mind </li></ul></ul><ul><li>Interference </li></ul><ul><ul><li>operates in unlicensed 2.4 GHz spectrum </li></ul></ul><ul><ul><li>competes with other products e.g microwave ovens! </li></ul></ul><ul><li>Scarcity of “hotspots” </li></ul>
    52. 53. Bluetooth <ul><li>1998 </li></ul><ul><li>Goal: eliminate the need for cables </li></ul><ul><li>Short range - 10m </li></ul><ul><li>data rate - 1 Mb/s </li></ul><ul><li>Example of an ad-hoc network </li></ul><ul><ul><li>network formed on an “as-needed” basis </li></ul></ul>
    53. 54. Bluetooth Topology <ul><li>Piconet </li></ul><ul><ul><li>Two or more Bluetooth devices </li></ul></ul><ul><ul><li>One master </li></ul></ul><ul><ul><ul><li>regulates traffic between devices </li></ul></ul></ul><ul><ul><li>Remainder termed slaves </li></ul></ul><ul><li>Scatternet </li></ul><ul><ul><li>Two or more piconets </li></ul></ul><ul><li>Note that a device can be a member of more than one piconet at a given time. </li></ul>
    54. 55. Satellite
    55. 56. Satellite Telephony
    56. 57. Integrated Wireless Services
    57. 58. Future of Mobility <ul><li>Architecture of Seamless Enterprise Connectivity </li></ul><ul><li>Source: CSC NTIS </li></ul>Mobile devices can connect to office networks anytime from anywhere…. <ul><li>Current mobility is based on single wireless technologies. </li></ul><ul><li>Future will allow automatic configuration for seamless roaming amongst various wireless technologies…and, hence, greater coverage (ubiquitous). </li></ul>IP Backbone/ Internet Multi-mode terminal w/MobileIP client & IPSec Client Public WLAN 802.11 Access Points Ethernet WLAN Gateway & FA 802.11 Access Points Ethernet WLAN Gateway, HA, FA Home AAA Server Enterprise Corporate LAN VPN Firewall PDSN/FA/HA/Firewall CDMA WSP PCF BS BS MSC/RNC GGSN/FA/HA/ Firewall GSM/UMTS WSP BS BSC SGSN CGF BS
    58. 59. WLAN-3G Integration Overview <ul><li>There is not yet a defined standard architecture for 1x-EVDO WLAN Interworking via 3GPP2 (ITU CDMA2000 standards group), but loose integration is currently favored in preliminary drafts. </li></ul>Loose integration makes most sense because it allows office WLAN, public hotspot WLAN, home WLAN, and operator WLAN access. <ul><ul><li>WLAN/3G Integration – Loose and Tight Methods </li></ul></ul><ul><ul><li>SOURCE: Bell Labs IOTA 3G-WLAN IEEE Communications Publication </li></ul></ul>
    59. 60. WLAN-3G Integration Overview <ul><li>Two Types of Integration Services: </li></ul><ul><li>Simple IP Service: A mobile node (MN) acquires L2 authentication and then the WLAN gateway provides IP address. </li></ul><ul><ul><li>This results in lost sessions from 1xEVDO to WLAN b/c of change of IP address </li></ul></ul><ul><ul><li>Not optimized to support mobility. </li></ul></ul><ul><li>Mobile IP Service: User can roam heterogeneous networks. </li></ul><ul><ul><li>Utilizes mobile IP to allow IP address to seem unchanged to higher layer applications </li></ul></ul><ul><ul><li>Optimized for mobility </li></ul></ul>
    60. 61. WLAN-3G Integration- Mobile IP <ul><ul><li>Using Mobile IP for Handoffs Used for Seamless Roaming </li></ul></ul><ul><ul><li>SOURCE: Bell Labs IOTA Project IOTA CDMA2000 WLAN Whitepaper IEEE Comms </li></ul></ul><ul><ul><li>IP Address </li></ul></ul><ul><ul><li>is </li></ul></ul><ul><ul><li>Constant </li></ul></ul>
    61. 62. WLAN-3G Seamless Authentication <ul><ul><li>Authentication across multiple technologies must be seamless </li></ul></ul><ul><ul><ul><li>Client driver intelligence to determine when to switch entirely from WLAN to CDMA, CDMA to WLAN, or WLAN to WLAN resulting in overhead usage but assuring higher layer sessions are kept active. </li></ul></ul></ul><ul><ul><ul><ul><li>Software is responsible for Mobile IP on client </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Must support both interfaces (WLAN & 1x-EVDO) and corresponding access techniques: Office, Public Hotspot, Home, etc… </li></ul></ul></ul></ul>
    62. 63. WLAN-3G Seamless Authentication <ul><ul><ul><li>Link security of interworking architecture must accommodate a mutual technique for authentication or client intelligence regarding which credentials to present for authentication. </li></ul></ul></ul><ul><ul><ul><ul><li>For example: Client supporting hotspot proprietary access technique while office access is determined via 802.1x. Client must realize which network it is trying to access, and then present the proper authentication credentials. Similarly, if accessing the 1xEV-DO network, it must present proper credentials. </li></ul></ul></ul></ul>