EE5406 Wireless Network Protocols –
Network Architectures
Dr. David Wong Tung ChongEmail: [email protected]
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.
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