EE5406 Wireless Network Protocols –

Network Architectures

Dr. David Wong Tung ChongEmail: wongtc@i2r.a-star.edu.sg

Website: http://www1.i2r.a-star.edu.sg/~wongtc/course.html

Academic Year 2010/2011

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Outline • Network Architectures

– GSM (2G Cellular)– GPRS (2G+ Cellular)– UMTS (3G Cellular)– LTE (3.9G Cellular)– LTE Advanced (4G Cellular)– IEEE 802.16 WiMAX WMAN– IEEE 802.11 WLAN– IEEE 802.15.1 Bluetooth WPAN– IEEE 802.15.4 Zigbee WPAN– ECMA 368 (WiMedia) WPAN– IEEE 802.15.3c WPAN– ECMA 387 WPAN

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GSM (2G Cellular)BSS – base station subsystemMT – mobile terminalNSS – network and switching

subsystemOSS – operation and support

subsystemBTS – base transceiver

stationsBSC – base station controllerAuC – authentication centerEIR – equipment identity

registerHLR – home location registerVLR – visitor location registerMSC – mobile switching centerGMSC – gateway MSCPSTN – public switched

telephone networkPLMN – public land mobile

networkISDN – integrated services

digital network

Figure 1. Global System for Mobile Communications (GSM) Network Architecture

PSTN,PLMN,ISDN GMSC MSC

AuC,EIR HLR VLR

NSS

BSC

BTSBTS

BTS

OSS

BSC

BTSBTS

BTS

BSS

MT MT MT MTMT MT

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GSM (2G Cellular)• The GSM system consists of three subsystems

– Base station subsystem (BSS)– Network and switching subsystem (NSS)– Operation and support subsystem (OSS)

• Base station subsystem (BSS)– BSS consists of

• Base transceiver stations (BTSs)• Base station controller (BSC)

– The role of the BSS is to provide transmission paths between themobiles and the NSS.

– The BTS is the radio access point.– Each BTS serves one cell. – The main functions of the BSC are cell management, control of a

BTS and exchange functions.

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GSM (2G Cellular)• Network and switching subsystem (NSS)

– NSS includes switching and location management functions.– NSS consists of

• mobile switching center (MSC)• home location register (HLR)• visitor location register (VLR)• gateway MSC (GMSC)• authentication center (AuC)• equipment identity register (EIR)

– The MSC is a complete exchange with switching and signaling capabilities.– GMSC provides interface between the mobile network and public switched

telephone network (PSTN), public land mobile network (PLMN) and integrated services digital network (ISDN).

– MSC is capable of routing calls from the BTS and BSC to mobile users in the same network (through BSC and BTS) or to users in the PSTN, PLMN and ISDN (through GMSC) or to answering machines integrated within the MSC.

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GSM (2G Cellular)– HLR and VLR are databases for location management.– The HLR stores the identity and user data of all subscribers

belonging to the mobile operator for both local and aboard (roaming) users.

– The VLR contains the permanent data found in the HLR of the user’s original network for all subscribers currently residing in itsMSC serving area.

– That is, VLR contains data of its own subscribers of the networkthat are in its serving area, as well as that (temporary data) of roamers from other GSM networks.

– The AuC is related to HLR and contains sets of parameters needed for authentication procedures for the mobile stations.

– EIR is an optional database that contains numbers of the mobile phone equipments.

– The purpose of EIR is to prevent usage of stolen mobile stations or to bar malfunctioning equipment.

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GPRS (2G+ Cellular)

PSTN,PLMN,ISDN

GMSC

MSC/VLR

HLR

GSM core

BSC

BTSBTS

BTS

BSS

SGSN

IP backbone network

Internet Data network

GGSN GGSN

GPRS core

MT MT

Figure 2. General Packet Radio System (GPRS) Network Architecture

BSS – base station subsystemMT – mobile terminalBTS – base transceiver stationsHLR – home location registerVLR – visitor location registerGMSC – gateway mobile

switching centerPSTN – public switched

telephone networkPLMN – public land mobile

networkISDN – integrated services digital

network SGSN – serving GPRS support

nodeGGSN – gateway GPRS support

node

MT MT

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GPRS (2G+ Cellular)• GPRS is a hardware and software upgrade to the existing GSM

system.• Two new network nodes are added:

– Serving GPRS support node (SGSN)– Gateway GPRS support node (GGSN)

• SGSN is responsible for the delivery of packets from/to mobile stations within its service area.

• Its main tasks are– Mobility management:

• Location management• Attachment/detachment

– Packet routing– Logical link management – Authentication– Charging functions

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GPRS (2G+ Cellular)• GGSN acts as an interface between the GPRS packet network

and external packet-based networks like the Internet.• It converts protocol data packet (PDP) address from the external

packet-based networks to the GSM address of the specified user and vice versa.

• For each session in GPRS, a PDP context to describe the session is created.

• It describes– PDP type (e.g., IPv4)– PDP address

• assigned to the mobile station for that session only – Requested quality of service (QoS) profile– Address of the GGSN

• the access node to that packet network• There may be several SGSNs or GGSNs.• All GPRS support nodes are connected through an IP-based

GPRS backbone network.

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GPRS (2G+ Cellular)• HLR stores the followings:

– User profile– Current SGSN address– PDP address(es)

• e.g., IP address for communication with Internet• MSC/VLR is extended with additional functions that allows

coordination between GSM circuit-switched services (e.g., telephony) and GPRS packet-switched services.

– Packet-switched services– Real-time multimedia– World Wide Web (WWW)– File download – E-mail

• Each of these services has different QoS requirements.

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GPRS (2G+ Cellular)• GPRS QoS profiles

– Service precedence• High priority• Normal priority• Low priority

– Reliability - Transmission characteristics of the GPRS network• Loss probability• Duplication• Misinsertion• Handling of corruption of packets

– Delay• Average delay• Maximum delay• 95% of all transfer

– Throughput• Mean bit rate • Maximum bit rate

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GPRS (2G+ Cellular)• GPRS has three states for location management:

– Idle– Ready– Standby

• In idle state, the network does not know the location of the mobile station and no PDP context is associated with the station.

• When the mobile station sends or receives packets, it is in ready state.

• In this state the network knows which cell the user is in.• After being silent for a period of time, mobile station reaches

standby state.

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GPRS (2G+ Cellular)• To locate a mobile,

– In standby state• a GSM location area is divided into several routing areas (RAs)• the network performs paging in the current RA

– In ready state• there is no need for paging

– In idle state• the network is paging all BTSs in the current location of the mobile

station• GPRS utilizes the same radio access network as GSM.• Third generation mobile networks have defined different radio

interfaces to provide higher bit rate services to users.

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PSTN,PLMN,ISDN

GMSCMSC/VLR

HLR

Core network

SGSN

Internet

Other data network

GGSN

GGSN

CS domain

PS domain

External networksUTRAN

Node B

Node B

Node B

Node B

RNC

RNC

::

::

::

MT

MT

MT – mobile terminalNode B – a network component

that serves one cellRNC – radio network controllerHLR – home location registerVLR – visitor location registerMSC – mobile switching centerGMSC – gateway MSC CS – circuit-switchedPS – packet-switchedPSTN – public switched

telephone networkPLMN – public land mobile

networkISDN – integrated services

digital network SGSN – serving GPRS support

nodeGGSN – gateway GPRS support

nodeUTRAN – UMTS Terrestrial

Radio Access Network

Figure 3. Universal Mobile Telecommunications System (UMTS) Network Architecture

MT

MT UMTS (3G Cellular)

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UMTS (3G Cellular)• UMTS’s basic architecture is split into two domains:

– User equipment (UE) domain– Infrastructure domain

• UE is used by users to access UMTS services.• It includes identity module and mobile equipment.• The mobile equipment performs radio communication

with the network and contains applications for the services.

• The infrastructure domain is further split into two domains: – Network access (NA) domain– Core network (CN) domain

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UMTS (3G Cellular)• The NA domain consists of physical entities (nodes), which

manage the radio resources.• The CN domain consists of physical entities, which provide

support for the features and telecommunication services like call management, mobility management, etc.

• There are two types of NA:– Base station subsystem (BSS)– Radio network system (RNS)

• BSS is the GSM radio access network solution, which is also used by GPRS.

• BSS consists of the base station controller (BSC) and base transceiver stations (BTSs).

• Each BTS serves one cell.• Usually several BTSs are grouped in a base station and place

on a single site.

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UMTS (3G Cellular)• For UTRAN, network elements are responsible for

– Radio resource management– Handover management– Power control

• RNS is the network system, which corresponds to the GSM BSS.• However, RNS is significantly different from the GSM access

operation.• RNS consists of the radio network controller (RNC), which controls

the radio access nodes called Node B.• A Node B is a network component that serves one cell.• There are different types of Node B like macrocells, microcells and

picocells with different requirements in traffic, coverage and services.

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UMTS (3G Cellular)• There are two types of Node B:

– Node B FDD– Node B TDD

• Node B FDD is planned for wider coverage area (macrocells, microcells).

• Node B TDD is targeted to hot spot in coverage.• The core network consists of two domains:

– circuit-switched (CS) domain – packet-switched (PS) domain

• These two domains in CN are overlapping in some common elements.

• CS mode is the GSM mode of operation, while PS mode is supported by GPRS.

• The entities specific to CS domain are MSC and GMSC.• The entities specific to PS domain are GGSN and SGSN.

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UMTS (3G Cellular)• There are entities shared by both the CS and PS domains:

– Home subscriber server (HSS)– Authentication center (AuC)– Equipment identity register (EIR)– Visitor location register (VLR)– SMS-support nodes

• HSS is a master database for a given user with the following information:– user identification (numbering, address information)– user security information (authentication, authorization)– user location information– user profile information (to services the user has access)

• HLRs for CS and PS domains are subsets of HSS.• HSS also provides IP multimedia functionality in the core network.• Other common entities have similar functions as described for GSM

and GPRS.

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PDN GWServing GW

EPCMME

IP network

PSTN

P/I/S-CSCF

PCRF

External networksE-UTRAN

eNode B

eNode B

eNode B

eNode B

::

MT

MT

MT – mobile terminaleNode B – an evolved network

component that serves one cellServing GW – serving gatewayMME – mobility management entityHSS – home subscriber serverPDN GW – packet data network

gatewayPCRF – policy and charging rules

functionsEPC – evolved packet coreWLAN – wireless local area networkP/I/S-CSCF –

proxy/interrogating/serving –call session control function

MGCF – media gateway control function

MGW – media gateway IMS – IP multimedia subsystem IP – internet protocolPSTN – public switched telephone

networkE-UTRAN – Evolved UMTS

Terrestrial Radio Access Network

Figure 4. Long Term Evolution (LTE) Network Architecture

HSS

MGW

MGCF

IMS

Other Access Types (WLAN,…)

MT

MT LTE (3.9G Cellular)

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LTE (3.9G Cellular)• In the evolved UMTS evolution, also known as Evolved Packet System

(EPS), the new blocks are– the Evolved UTRAN (E-UTRAN), also known as the evolved access

network.– and the Evolved Packet Core (EPC), also known as the evolved packet core

network.• E-UTRAN consists of a networks of evolved nodeBs (eNodeBs).• There is no centralized controller in E-UTRAN.• Thus, the E-UTRAN architecture is known to be flat.• The eNodeBs are normally connected to each other by an interface

known as X2.• The eNodeBs are connected to the mobility management entity (MME)

by an interface known as S1-MME and to the serving gateway (GW) by an interface known as S1-U.

• The protocols that is running between the eNodeBs and the MT (or user equipment (UE)) are known as the Access Stratum (AS) protocols.

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LTE (3.9G Cellular)• The E-UTRAN is responsible for all radio-related functions like

– Radio Resource Management• All functions related to the radio bearers

– Radio bearer control– Radio admission control– Scheduling– Dynamic allocation of resources to UEs in both the uplink and downlink

– Header Compression• Compress IP packet headers• Otherwise, significant overhead for small packets such as voice over IP

(VoIP)– Security

• Encrypted all data that are sent over the radio interface– Connectivity to the EPC

• This consists of the signalling towards the MME and the bearer path towards the serving GW.

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LTE (3.9G Cellular)• The EPC consists of several functional entities

– Mobility management entity (MME)– Serving gateway (GW)– Packet data network (PDN) gateway– Policy and charging rules function (PCRF)

• MME– In charge of all the control plane functions related to subscriber and session

management– Security procedures– Terminal-to-network session handling– Idle terminal location management

• The MME is connected to the home subscriber server (HSS) throughan interface known as S6.

• HSS is the concatenation of the home location register (HLR) and the authentication center (AuC).

• HSS supports the database containing all subscription information.

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LTE (3.9G Cellular)• Serving GW

– Termination point of packet data interface towards E-UTRAN– Serves as local mobility anchor when UEs move across eNodeBs

• Packets are routed through this point for intra E-UTRAN mobility and mobility with other 3GPP technologies such as 2G GSM and 3G UMTS.

• PDN GW– Termination point of packet data interface towards PDN.– Anchor point for sessions towards the PDN.– Supports policy enforcement features (which apply operator-

defined rules for resource allocation and usage) – Packet filtering (like deep packet inspection for virus signature

detection)– Evolved charging support (like per URL charging)

• URL is an address of a web page on the world wide web (WWW).

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LTE (3.9G Cellular)• Policy and charging rule functions (PCRF)

– Responsible for policy control decision-making and for controlling the flow-based charging functionalities in the PDN GW.

– Provides QoS authorization of data flow through PDN GW. – Ensures user’s subscription profile.

• The IP multimedia subsystem (IMS) is a generic platform offering IP-based multimedia services.

• The call session control function (CSCF) play a key role in IMS architecture.

• CSCF has three types– Proxy– Interrogating– Serving

• CSCF establishes, terminates and modifies IMS sessions.

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LTE (3.9G Cellular)• Multimedia gateway control function (MGCF)

– Supports call control protocol conversion.– Supports media gateway (MGW).– Supports interrogating CSCF.

• MGW– Responsible for media conversion.– Responsible for bearer control.– Payload processing (e.g., codec, echo canceller, …).

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LTE Advanced (4G Cellular)

PDN GWServing GW

EPC

MME

IP network

PSTN

P/I/S-CSCF

PCRF

External networksE-UTRAN

eNode B

eNode B

HeNode B

HeNode B

MT

MT

MT – mobile terminalRN – relay nodeeNode B – an evolved network

component that serves one cellHeNodeB – an evolved network

component that serves one femtocell

Serving GW – serving gatewayMME – mobility management entityHSS – home subscriber serverPDN GW – packet data network gatewayPCRF – policy and charging rules

functionsEPC – evolved packet coreWLAN – wireless local area networkP/I/S-CSCF – proxy/interrogating/serving

–call session control functionMGCF – media gateway control functionMGW – media gateway IMS – IP multimedia subsystem IP – internet protocolPSTN – public switched telephone

networkE-UTRAN – Evolved UMTS Terrestrial

Radio Access Network

Figure 5. Long Term Evolution (LTE) Advanced Network Architecture

HSS

MGW

MGCF

IMS

Other Access Types (WLAN,…)

HeNB-GW

MT

MT

MT

RN

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LTE Advanced (4G Cellular)• The E-UTRAN for LTE Advanced can support Home eNodeB

(HeNodeB) which is also known as a femtocell.– HeNodeB are basically eNodeB of lower cost for indoor coverage

improvement.– HeNodeB can be connected to the evolved packet core (ECP) directly or

via a HeNodeB gateway (GW) which provides support for a large number of HeNodeBs.

• The E-UTRAN for LTE Advanced is also considering support of relay nodes and enhanced relaying strategies for increased coverage, higher data rates and better QoS performance and fairness for different users.

• The EPC is not undergoing major changes from the standardized system and architecture evolution (SAE) project.

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IEEE 802.16 WiMAX WMANInternet

RN

RNRN

RN

Wimax BSWimax BSs

MS MS

MS MSMS

MS

MS

MS

MS

Figure 6. IEEE 802.16 WiMAX Wireless Metropolitan Area Network (WMAN) Network Architecture

BS – base stationRN – relay nodeMS – mobile

subscriber/stationASN – access services

networkASN GW – ASN gatewayCSN – core services

networkPSTN – public switched

telephone networkPMP – point-to-multipoint MHR – multi-hop relay

ASN GWASN CSN

CSN

Other operator CSN

PSTN

3G

MSMS

MHR mode

Mesh modePMP mode

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IEEE 802.16 WiMAX WMAN• The access services network (ASN) is the access network of

WiMAX.• ASN provides the interface between the user and the core

services network (CSN).• ASN

– Handover– Authentication through the proxy authentication, authorization and

accounting (AAA) server– Radio resource management– Interoperability with other ASNs– Relay of functionality between CSN and mobile station (MS), e.g.,

IP address allocation

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IEEE 802.16 WiMAX WMAN• ASN gateway

– Connection and mobility management.– Interservice provider network boundaries through processing of

subscriber control and bearer data traffic.– Serves as an extensible authentication protocol (EAP)

authenticator for subscriber identity.– Acts as a remote authentication dial-in user service (RADIUS)

client to the operator’s AAA servers.• CSN

– Transport, authentication and switching part of the network.– Represents the core network in WiMAX.– Consists of home agent (HA), AAA system and IP servers

(gateways to other networks like Internet, public switched telephone network (PSTN), 3G, etc.)

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IEEE 802.11 WLAN –Infrastructure Mode

Distribution system

IEEE 802.x LAN

Basic service set

AP/STA1

STA2STA3

STA4

Basic service set

AP/STA5

STA6STA7

STA8

Extended service set

Portal

Figure 7. IEEE 802.11 WLAN (Infrastructure Mode) Network Architecture

AP – access pointSTA – stationLAN – local area network

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IEEE 802.11 WLAN –Infrastructure Mode

• The smallest building block of a wireless LAN is a basic service set (BSS).

• BSS consists of a number of stations (STAs) executing the same medium access control (MAC) protocol and competing for access tothe same shared wireless medium.

• A BSS may be isolated or it may be connected to a backbone distribution system (DS) through an access point (AP).

• The access point functions as a bridge.• The MAC protocol may be fully distributed or controlled by a central

coordination function housed in the access point.• The BSS generally corresponds to a cell.• The DS can be a switch, a wired network or a wireless network.• The figure above shows the simplest configuration, where each

station belongs to a single BSS.• That is, each station is within wireless range only of other stations

within the same BSS.• It is also possible for two BSSs to overlapped geographically, so that

a single station could participate in more than one BSS.

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IEEE 802.11 WLAN –Infrastructure Mode

• Furthermore, the association between a station and a BSS is dynamic.• Stations may turn off, come within range, and go out of range.• An extended service set (ESS) consists of two or more basic service

sets (BSSs) interconnected by a distribution system (DS).• Typically, the distribution system is a wired backbone LAN but can be

any communications network.• The extended service set appears as a single logical LAN to the logical

link control (LLC) level.• Figure 7 shows the access point (AP) is implemented as part of a

station.• The AP is the logic within a station that provides access to the DS by

providing DS services in addition to acting as a station.• A portal is used to integrate the IEEE 802.11 architecture with a

traditional wired LAN (IEEE 802.x).• The portal logic is implemented in a device such as a bridge or a router,

that is part of the wired LAN, and is attached to the distribution system (DS).

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IEEE 802.11 WLAN – Ad Hoc Mode

STA2

STA3

STA4

STA1

Figure 8. IEEE 802.11 WLAN (Ad Hoc Mode) Network Architecture

STA – station

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IEEE 802.11 WLAN – Ad Hoc Mode

• In the ad hoc network architecture, stations are connected directly to each other in an ad hoc manner without an AP.

• This is like a mesh network topology or sometimes known as peer-to-peer network topology.

• This mode of operation is also known as an independent BSS (IBSS).

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IEEE 802.11 WLAN – Wireless Mesh Mode

Distribution system

IEEE 802.x LAN

BSS

STA2STA3

STA4BSS

AP/STA5

STA6STA7

STA8

Extended service set

Portal

Figure 9. IEEE 802.11 WLAN (Wireless Mesh Mode) Network Architecture

AP – access pointSTA – stationLAN – local area

networkBSS – basic service

set

BSS

STA10

STA11

AP/STA9

BSS

STA13

STA14

AP/STA12

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IEEE 802.11 WLAN – Wireless Mesh Mode

• In the wireless mesh network topology, the distribution system can be a wireless mesh network among the access points.

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IEEE 802.15.1 Bluetooth WPAN

Wired LAN

Bluetooth piconet

BTS

PSTN

Cellular Network

AP – access pointSTA – stationLAN – local area network PSTN – public switched

telephone networkBTS – base transceiver station

Figure 10. Bluetooth Network Architecture

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IEEE 802.15.1 Bluetooth WPAN

• Bluetooth can be used to connect different devices like mobile phone, printer, walkman, etc., to a laptop in a small personal area network called a piconet.

• The laptop can be connected to the LAN via an access point.

• A mobile phone can also be connected to a base station in a cellular network which in turn is connected to a PSTN.

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IEEE 802.15.4 Zigbee WPAN

Full-function device (FFD)

Reduced-function device (RFD)

PANC – Personal area network coordinator

(a) (b)

Figure 11. IEEE 802.15.4 Zigbee Network Topologies (a) star; (b) peer-to-peer

PANC

PANC

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IEEE 802.15.4 Zigbee WPAN• The PAN coordinator is the principal controller of a PAN.• PANC is a full-function device (FFD).• PANC can initiate a communication, terminate the

communication and route it around the network.• An IEEE 802.15.4 network has exactly one PANC.• An FFD can connect to both FFDs and reduced-function devices

(RFDs).• A RFD can connect to only a FFD.• Simple applications of a RFD are a light sensor and a lighting

controller.• A FFD can take up roles of a coordinator and a router.

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ECMA 368 (WiMedia) WPAN

Wired LAN

ECMA 368

piconet

BTS

PSTN

Cellular Network

AP – access pointSTA – stationLAN – local area network PSTN – public switched

telephone networkBTS – base transceiver stationPNC – piconet coordinator

Figure 12. ECMA 368 Network Architecture

PNC

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ECMA 368 (WiMedia) WPAN• WiMedia can be used to connect different devices like mobile phone,

printer, storage device, MP3/4 player, etc., to a laptop in a small wireless personal area network (WPAN) such as a piconet as known in Bluetooth.

• A WPAN for WiMedia is shown in Figure 12. • The connectivity between the laptop and the devices can be done using

Wireless USB. • Wireless USB makes use of a type of reservation known as Private

Distributed Reservation Protocol in WiMedia medium access control. • The laptop can be connected to the local area network (LAN) via an

access point. • A mobile phone can also be connected to a base station in a cellular

network which in turn is connected to a public switched telephone network (PSTN).

• This example shows a star topology but WiMedia does not need to be in this topology only.

• As it has a distributed medium access control, WiMedia can have other topologies, e.g., those with mesh-connectivity.

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IEEE 802.15.3c WPAN

Wired LAN

IEEE 802.15.3c

piconet

BTS

PSTN

Cellular Network

AP – access pointSTA – stationLAN – local area network PSTN – public switched

telephone networkBTS – base transceiver stationPNC – piconet coordinator

Figure 13. IEEE 802.15.3c Network Architecture

PNC

HDTV

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IEEE 802.15.3c WPAN• The PHY specifies three modes and one common mode. • The three PHY modes are as follows:

– Single carrier (SC) mode optimized for low power and low complexity.

– High-speed interface (HSI) mode optimized for low-latency bidirectional data transfer.

– Audio/video (AV) mode optimized for the delivery of uncompressed, high-definition video and audio.

• Also defined as a part of the alternate PHY is common-mode signaling, which is a PHY mode that allows devices using different PHY modes to communicate.

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ECMA 387 WPAN

ECMA 387

piconet

AP – access pointSTA – stationLAN – local area network PNC – piconet coordinatorHDTV – high definition television

Figure 14. ECMA 387 Network Topologies (a) star; (b) mesh (types A and B devices)

PNC

(a) (b)

Wired LAN

HDTV

HDTV HDTV HDTVA

A A

A

B

B B

B

AA

B

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ECMA 387 WPAN• The standard provides high rate wireless personal area

network (including point-to-point) transport for both bulk data transfer and multimedia streaming.

• The key usage cases and applications are:– High definition (uncompressed / lightly compressed) AV

streaming– Wireless docking station– Short Range “Sync & Go”.

• The standard defines two device types that interoperate with their own types independently and that can coexist and interoperate with the other types.

• Thus, it offers a heterogeneous network solution that provides interoperability between all device types.

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ECMA 387 WPAN• The two device types are defined as follows:• A type A device offers video streaming and WPAN applications in 10-

meter range line-of-sight (LOS)/non-line-of-sight (NLOS) multipathenvironments.

• It uses high gain trainable antennas. • This device type is considered as the ‘high end’ - high performance

device.• A second type B device offers video and data applications over shorter

range (1-3 meters) point-to-point LOS links with non-trainable antennas.

• It is considered as the ‘economy’ device and trades off range and NLOS performance in favour of low cost implementation and low power consumption.

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References• David Tung Chong Wong, Peng-Yong Kong, Ying-Chang Liang, Kee Chaing

Chua and Jon W. Mark, Wireless Broadband Networks, John Wiley and Sons, 2009.

• Yang Xiao and Yi Pan (Editors), Emerging Wireless LANs, Wireless PANs, and Wireless MANs, John Wiley and Sons, 2009.

• P. Lescuyer and T. Lucidarme, Evolved Packet System (EPS), John Wiley and Sons, 2008.

• Stefania Sesia, Issam Toufik and Matthew Baker, LTE – The UMTS Long Term Evolution: from Theory to Practice, John Wiley and Sons, 2009.

• Yan Zhang (Editor), WiMax Network Planning and Optimization, CRC Press, 2009.

• Tony Janevski, Traffic Analysis and Design of Wireless IP Networks, ArtechHouse, 2003.

• William Stallings, Wireless Communications and Networks, Prentice Hall, 2002. • Amjad Umar, Mobile Computing and Wireless Communications, NGE Solutions,

2004.• Ecma/TC48/2010/025 (Rev. 2 – 30 June 2010), ECMA-387 2nd Edition: High

Rate 60GHz PHY, MAC and HDMI PAL Whitepaper, June 2010.