QoSQoS guaranteed Technology in guaranteed Technology in Ubiquitous Digital Home NetworksUbiquitous Digital Home Networks
2004. 8. 312004. 8. 31
김김 재재 현현
ee--mail: [email protected], mail: [email protected],
home: http://home: http://ajou.ac.kr/~jkimajou.ac.kr/~jkimSchool of Electrical EngineeringSchool of Electrical Engineering
Ajou UniversityAjou University
2KJH
IEEE 802.11 Wireless LANIEEE 802.11 Wireless LAN
IEEE 802.15 Wireless PANIEEE 802.15 Wireless PAN
Fast EthernetFast Ethernet
IEEE 1394IEEE 1394
QoSQoS guaranteed technology in Home guaranteed technology in Home
NetworksNetworks
Talk OutlineTalk Outline
3KJH
IEEE 802.11 Wireless LANIEEE 802.11 Wireless LAN
IEEE 802.15 Wireless PANIEEE 802.15 Wireless PAN
Fast EthernetFast Ethernet
IEEE 1394IEEE 1394
QoSQoS guaranteed technologyguaranteed technology in Home in Home networksnetworks
4KJH
IEEE 802.11 Overview IEEE 802.11 Overview (PHY & Data Rates)(PHY & Data Rates)
– CCK : Complementary Code Keying – PBCC: Packet Binary Convolutional Code
OFDM, CCK-OFDMOFDMMulti48
OFDM, CCK-OFDMOFDMMulti54
OFDM, CCK-OFDMOFDMMulti36
PBCCMulti33
CC-OFDMOFDMOFDMMulti24
PBCCSingle22
OFDM, CCK-OFDMOFDMMulti18
CC-OFDMOFDMOFDMMulti12
PBCCCCKPBCCCCKSingle11
OFDM, CCK-OFDMOFDMMulti9
CC-OFDMOFDMOFDMMulti6
PBCCCCKPBCCCCKSingle5.5
DS/SSDS/SSSingle2
DS/SSDS/SS Single1
OptionalMandatoryOptionalMandatoryOptionalMandatory
PHY Modulation SchemeCarrier
Data Rate
(Mbps)
2.4GHz5.2 GHzFrequency
802.11g802.11b802.11a
5KJH
802.11a/g PHY802.11a/g PHY
OFDM Subcarrier Frequency Allocation
Total 52 subcarriers (-26 ~ 26) using 64 FFT48 subcarriers for data4 subcarriers for pilot (-21, -7, 7, 21)20MHz channel
Runs in 5GHz U-NII bands (in case of US)300MHz from 5.15-5.35(8 Ch.) & 5.725-5.825GHz (4 Ch.)Total 12 channels available
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IEEE 802.11b PHYIEEE 802.11b PHY
Runs in 2.4GHz ISM bands (US : 2.412 – 2.462 GHz)11 22MHz channel
3 different transmission rates:Complementary Code Keying (CCK) for 5.5 & 11 MbpsDirect-Sequence Spread Spectrum (DSSS) for 1 & 2 MbpsPacket Binary Convolutional Code (PBCC) for 5.5, 11, 22, 33 Mbps
Channel 1 Channel 6 Channel 11
Frequency
Power
7KJH
Major Task Groups in 802.11 standardMajor Task Groups in 802.11 standard
High Throughput802.11 n
Radio Resource Measurement Enhancements802.11 k
MAC Enhancements for Enhanced Security802.11 i
Spectrum Managed 802.11a802.11 h
Higher Rate (20+ Mbps) in the 2.4GHz802.11 g
Inter Access Point Protocol802.11 f
MAC Enhancements for Quality of Service802.11 e
PHY & MAC for 2.4 GHz802.11 b
PHY & MAC for 5 GHz802.11 a
ObjectivesTask Group
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Wireless LAN ArchitectureWireless LAN Architecture
Ad hoc WLAN ModePeer-to-peer communication only
Independent Basic Service Set IBSS
Infrastructure WLAN ModeNo peer to peer communication, always through AP
Distribution system : Connect two or more BSS
BSS-A BSS-B
AP-B
Distribution System
AP-A
Ad hoc network Infrastructure network
9KJH
Service Types and Coordination Functions Service Types and Coordination Functions
Asynchronous Service : Data service, FTP, Web, etc.Contention TrafficDCF (Distributed Coordination Function)Distributed controlled by STA
Isochronous Service : Delay sensitive traffic, voice, etcContention-Free TrafficPCF (Point Coordination Function) Centralized controlled by AP (Access Point)
Super Frame Concept
Superframe
Contention-Free Contention
Burst Traffic
10KJH
Distributed Coordination Function (DCF)Distributed Coordination Function (DCF)
CSMA/CA protocol
Use different Inter Frame Space (IFS) to differentiate trafficSIFS (Short Inter Frame Space) : High Priority
PIFS (PCF Inter Frame Space) : Medium Priority
DIFS (DCF Inter Frame Space) : Low Priority
DIFS Contention Window
Slot time
Busy Medium
Defer Access
Backoff-Window Next Frame
Backoff slot reduced when channel is idle
SIFS
PIFSDIFS
Sense channel during DIFS
KJH
Distributed Coordination Function (DCF)Distributed Coordination Function (DCF)
Baseline 802.11 MAC includes a virtual carrier sensing scheme to address the Hidden Terminal Problem
RTS
DATA
ACK
전송 지연
CTS
ACK
STA 2로 부터 hidden terminal
STA 1으로 부터 CTS받은 후 NAV Set
DATA DATA
ACK
STA 2
STA 1
STA 3
STA 4
STA 5
DIF
S
DIF
SD
IFS
SIF
S
SIF
S
SIF
S
SIF
S
SIF
S
SIF
S
DIF
S
Randombackoff=2
Randombackoff=10
Randombackoff=6
Randombackoff=8
Time
STA 2 패킷 전송 감지로 전송 시도 지연 Backoff slot=2
RTS수신후 NAV Set
STA1STA2 STA5
12KJH
Exponential Exponential BackoffBackoff AlgorithmAlgorithm
CW : Contention Window ( 0 to CW_min ~ CW_max ) :
CW is doubled when transmission is failed
CW_min : 11.a = 15, 11.b = 7, 11.b HR = 31, CW_max = 1023
Slot time : Receiver turn on time + propagation delay + media busy detection time
Backoff delay = INT( CW Random() ) Slot Time× ×
CWmin=7
3163
127
CWmax=255 255
0
50
100
150
200
250
300
1 2 3 4 5 6
Example
13KJH
Point Coordination Function (PCF)Point Coordination Function (PCF)
Send Request in Contention Period
AP poll STA by the polling list
CF-B CF-B CF-B CF-BCF-B
Dynamic Polling ListPolling List Polling List
Delete from list when idle too long
Add to list when activityDelete from list when idle too long
Async Traffic
SFP
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Contention Free OperationContention Free Operation
Two consecutive frames are separated by SIFS
CFP lengths depend on traffic amount Maximum length announced by AP; used for NAV set
Beacon D1+Poll
NAV
SIFS
SIFS
U1+Ack
D2+Ack+Poll
SIFS
U2+Ack
SIFS
SIFS
CF-End
Uplink
Downlink
Contentio Free Period (CFP) for PCF
ContentionPeriod (CP)
for DCF
Contention Free Period Repetition Interval (CFPRI) or Superframe
Reset NAV
CF_MAX_DurationDx - downlink frame to STA xUx - uplink frame from STA x
PIFS
15KJH
QoS Support in 802.11eQoS Support in 802.11e
HCF (Hybrid Coordination Function)Two channel access mechanism :
Contention based channel accessControlled based channel access
EDCA (Enhanced Distributed Channel Access)Using Arbitration IFS, differentiate QoS
HCCA (HCF Controlled Channel Access)Channel access for parameterized QoS
Transmission Opportunity (TXOP)Multiple frames can be transmitted during a TXOP with certain rulesEDCA TXOP – acquired by beaconPolled TXOP – acquired by QoS CF poll
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EDCA EDCA (Enhanced Distributed Channel Access)(Enhanced Distributed Channel Access)
Access category (AC) as a virtual DCF4 ACs implemented to support 8 user prioritiesEDCA Parameters
AIFSAIFS[AC]=SIFS+AIFSN[AC]*aSlotTime
Contention Window ParametersMax. TXOP duration(TXOP Limit)
BackoffAIFSN[0]
BO[0]
BackoffAIFSN[1]
BO[1]
BackoffAIFSN[2]
BO[2]
BackoffAIFSN[3]
BO[3]
Virtual Collision HandlerTransmission Attempt
AC_BK AC_BE AC_VI AC_VO
VoiceAC_VO7
VoiceAC_VO6
VideoAC_VI5
VideoAC_VI4
Video ProbeAC_VI3
Best EffortAC_BE0
BackgroundAC_BK2
BackgroundAC_BK1
Destination
(Informative)Access
Category(AC)
Priority
(Same as 802.1D)
1 2 30 4 5 6 7
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Typical TXOPTypical TXOP
Once a STA has gained the medium for transmission, there are limits on how long it can transmit or burstEDCA TXOP Defaults
TXOP limit value of 0 indicates that a single packet may be transmitted at any rate for each TXOP
24Mbps = 0.5ms2Mbps = 6.2ms
6Mbps = 2.1ms1Mbps = 12.3ms
24Mbps = 0.5ms2Mbps = 6.2ms
6Mbps = 2.1ms1Mbps = 12.3ms
54Mbps = 0.2ms11Mbps = 1.2ms
AC_BK(Background)
54Mbps = 0.2ms11Mbps = 1.2ms
AC_BE(Best effort)
3.0ms6.0msAC_VI(Video)
1.5ms3.3msAC_VO(Voice)
TXOP Limit (802.11a/g)TXOP Limit(802.11b)AC
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EDCA EDCA (Enhanced Distributed Channel Access)(Enhanced Distributed Channel Access)
2(CWmin+1)/2-1(CWmin+1)/4-1AC_VI
2CWmin(CWmin+1)/2-1AC_VO
7CWmaxCWminAC_BE
3CWmaxCWminAC_BK
AIFSNCWmaxCWminAC
ACK RTS
CTS
SIFS SIFS
PIFS
AIFS[AC]
=DIFS
SIFS
AIFS[AC]
AIFS[AC]
high priority AC
medium priority AC
low priority AC backoff
backoff
defer accessContention Windows(counted in slots, 9us
count down as long as medium is idle,Back off when medium gets bust again
With 802.11a
aSlotTime: 9us
SIFS: 16us
PIFS: 25us
DIFS: 34us
AIFS: >=34 us
CWi+1 [AC]=min[ ( ( CWi[AC] + 1 )*PF[AC] ) - 1, CWmax]
PF : Persistent Factor
CW=rand[1,CWi+1]
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HCCA HCCA (HCF Controlled Channel Access)(HCF Controlled Channel Access)
Additional polling based controlled contention scheme for HC to learn the TXOPs needed by the stations
Contention Free Period, CFP(polling through HCF) Contention Period, CP (listen before talk and polling through HCF)
TXOP TXOP TXOP TXOP
TBTT
QoS CF-Poll QoS CF-PollCF-end
Beacon
Transmitted
by (Q)STAs
Transmitted
by HC
TBTTTime
RTS/CTS
Fragmented DATA/ACK
(polled by HC )
RTS/CTS/DATA/ACK
(after DIFS+backoff)
RTS/CTS
Fragmented DATA/ACK
(polled by HC )
20KJH
IEEE 802.11 Wireless LANIEEE 802.11 Wireless LAN
IEEE 802.15 Wireless PANIEEE 802.15 Wireless PAN
Fast EthernetFast Ethernet
IEEE 1394IEEE 1394
QoSQoS guaranteed technology in Home guaranteed technology in Home networksnetworks
21KJH
IEEE 802.15 OverviewIEEE 802.15 Overview
Star,Peer2peer
Piconet,Child piconet,
Neighbor piconet
Piconet,Scatternet TopologyTopology
CSMA/CATDMA
CSMA/CA,S-Aloha,
TDMA
FH/TDD79 Ch,
1600hop/secMACMAC
Low Rate/ZigbeeUWBHigh RateBluetoothObjectivesObjectives
Philips, MotorolaXtreme spectrum, TimedomainNokia,Sony,
EricssonMajor Major
VenderVender
10~20m5~10m10m(1mW)
100m(100mW)RangeRange
BPSK(868/915MHz)
O-QPSK(2.4GHz)
QAM (if Multi-band
OFDM)
QPSK, DQPSK, 16/32/64-QAM (11,22,33,44,55
Mbps)
GFSKModulationModulation
20k~250kbps100Mbps at 10m200Mbps at 4m
path to 400Mbps< 55Mbps
< 1Mbps(sync.)< 723Kbps(Async.)Data RateData Rate
868/915MHz2.4GHz
3.1GHz~10.6GHz2.4GHz2.4~2.4835GhzFrequency Frequency bandband
802.15.4802.15.3a802.15.3802.15.1
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IEEE 802.15.1 OverviewIEEE 802.15.1 Overview
ConceptShort Range : 0.01m - 10m (100m)Low Power : 1mW, 2.5 mW, 100 mWLow Cost : < $5
Can be used for Data (max 753 kbps) / Voice(3 64kbps) Access Appliance Cable replacementPersonal Ad-Hoc Connectivity
Standard (Bluetooth SIG and IEEE802.15.1)1999 : Version 1.0b2001 : Version 1.1 (1Mbps)Current : on going for Version 2.0 (2-11Mbps)
Topology Piconet, Scatternet
23KJH
Channel AllocationChannel Allocation
TDD/Single slot
Multi-slot allocation
24KJH
Service Profile and Protocol StackService Profile and Protocol Stack
Appropriate protocol stack for service profiles
Radio
BaseBand SCOACL
LMP
L2CAP
RFCOMM
PPP
IP
UDP TCP
OBEX
vCard/vCal
WAP
WAE
AT-Commands
TCS BIN
SDP
Example :
Dial Up Networking
FAX Profile
Example :
Headset profile
Audio Stream
- LMP : Link Manager Protocol - HCI :Host Control Interface - SDP : Service Discovery Protocol - L2CAP : Logical Link Control and Adaptation Protocol - TCS : Telephony Control protocol Spec. - SCO Synchronous Connection Oriented Link - ACL: Asynchronous Connectionless Link - OBEX OBject EXchange protocol - WAE : WAP Application Environment
25KJH
IEEE 802.15.3 IEEE 802.15.3 (High Rate)(High Rate) OverviewOverview
ObjectiveLow complexity, Low cost, Low power, Short Range, QoS Capable, Peer to peer communication, High data rate (> 20Mbps)
PHY 2.4GHz 5 Channel
MAC FunctionalityFast Connection Time Ad hoc Network QoS supportSecurity Dynamic MembershipEfficient data transfer
Topology Piconet, Child piconet, Neighbor piconetPiconet Coordinator (PNC), Device (DEV)
26KJH
MAC Frame FormatMAC Frame Format
Easy Connection and DisconnectionAuthentication
Addressing
Security-Key setting
Bootstrap
Any DEV can be PNC
Power save mode
MAC frame is in Superframe
- SFC : Secure Frame Count - SEC ID : Security ID
1
Stream index
3
Fragmentation control
1 1 2
SrcID
Dest
IDPNID
2
Frame control
MAC Header
Non SecureSecure
0 ~ 4 Ln
FCSFrame
payload
MAC frame body
0 ~ 4
FCS
8
Integrity Code
Ln
Security Payload
2
SFC
2
SECID
MAC frame body
27KJH
Superframe StructureSuperframe Structure
Beacon #m
Contention Access Period MCTA1 MCTA2
CTA1
CTA2 …
CTM n-1
CTAn
CFP (Contention Free Period)
Beacon #m
CAPAsynchronous Isochronous Asynchronous Isochronous
CFP (Contention Free Period)
Super frame #m-1 Super frame #m Super frame #m+1
1,000 ~ 65,535μs
CSMA/CAData/Control
S-ALOHAData/Control
TDMAData
- MCTA : Management Channel Time Allocation
28KJH
PiconetPiconetIndependent piconet: PNC and DEV
Dependent piconet Child piconet : # DEV > 255, extended area, Communication with PNC or DEV in parent piconetNeighbor piconet : when no available channel in parent piconet, communication only with PNC or DEV in neighbor piconet
Reserved time Beacon
CAP CTA1
CTA2 … CTA
n
CFPReserved time
BeaconContention
Access Period CTA 1 CTA 2 … CTA n
CFPBeacon
C-PNC
DEV2
DEV1
C-DEV 1
C-DEV
2
P-PNC
29KJH
IEEE 802.15.3a IEEE 802.15.3a (UWB)(UWB) OverviewOverview
UWB (Ultra-Wide Band) : Bandwidth > 500 MHz
CharacteristicsFrequency : 3.1GHz~10.6GHz
ERIP Emission level should be less than -41.3dBm/MHz
Data rate : 110 ~ 480 Mbps, Range : < 10m
Use IEEE802.15.3 MAC
fCfL fH
Narrow Band: (fH –fL) < 0.01*FC
UWB: (fH –fL) > 0.25*FC
Frequency (Hz)
Po
wer
sp
ectr
al
den
sity
(d
B)
30KJH
IEEE 803.15.3a PHY layer IEEE 803.15.3a PHY layer (Proposed)(Proposed)
55 – 480 Mbps28.5 Mbps – 1.2GbpsData rate
OFDM/ QPSK FDM+CDM+TDM (PSK)Modulation
13-17 band (528 MHz)BW: 2GHz, 4.8GHz, 1 or 2Bandwidth
Intel, TimeDomain, DTC, WisAir, GA, Femto Devices
XSI, SONYVendors
Peak to average ratio Prob.
Not verified yet
UWB Antenna
Complex to Sync.Difficulty
Easy to implement
robust to interference
Time to Market (’05 1Q)
Simple HW
Low cost, low power
Time to Market (’03 4Q)
Advantage
Multi Band OFDMSingle Band
Single Band vs. Multi-Band OFDM(MBOA)
3 5 7
802.15.3
High BandLow Band
10
EIRP Emission Level (-41.3 dBm/MHz)
2.4 GHz 3 10
-41.3 dBm/MHz
GHz
- EIRP (Equivalent Isotropic Radiated Power)
31KJH
IEEE 802.15.4 (IEEE 802.15.4 (ZigbeeZigbee) Overview) Overview
Low Rate (20, 40, 250Kbps), Low Cost, Low Power Short Range (< 10m)
Dynamic device addressing
Support for low latency devices
Reliable by fully handshake protocol
CSMA-CA channel access.
Low power consumption
Apply tou-Digital Network : Energy save, Consumer Electronics, Toy, Security
Health care check and monitoring System
TopologyStar or peer-to-peer topology
32KJH
Comparison of Comparison of ZigbeeZigbee and Bluetooth and Bluetooth
Take advantage of host processor power (ARM7…)
802.11 functionality but with simplified RF specifications
Minimum software and processing(80C51)
System design for eventual single-chip antenna-to-application realization
Cost Standpoint
Power model as a mobile phone
(regular charging)
Designed to maximize ad-hoc functionality
2+ year from ‘normal’batteries
Designed to optimize slave power
Power Consideration
DSSS
1M symbol/s
720kbps
FHSS
62.4k symbol/s
128kbpsAir interface
BluetoothZigbee
33KJH
IEEE 802.15.4 PHY IEEE 802.15.4 PHY (Frequency)(Frequency)
10~20m(1mW)
< -92dBm
53.2ms
1
BPSK
20kbps
868MHz
10~20m(1mW)
< -85dBm
4.25ms
16 (5MHz)
O-QPSK
250kbps
2.4GHz
10~20m(1mW)
< -92dBm
26.6ms
10 (2MHz)
BPSK
40kbps
915MHz
Range
Receiver sensitivity
Packet period
# of Channel
Modulation
Data Rate
Frequency
868MHz 902MHz 928MHz 2.4GHz 2.4835GHz
34KJH
802.15.4 MAC/PHY Frame Format802.15.4 MAC/PHY Frame Format
- FCS : Frame Check Sequence - MHR : MAC Header - MSDU : MAC Service Data Unit
- MAF : MAC Footer - FL : Frame Length - SFD : Start Frame Delimiter
- SHR : Synchronization Header - PHR : Physical Header - PPDU : Physical Protocol Data Unit
Physical Protocol Data Unit (PSDU)
SHR PHR Physical Service Data Unit (PSDU)
Preamble SFD FL
PPDU size : 11 + ( 4 to 20) + n (≤ 133 Octet)
MHR MSDU MAF
Frame control
Sequence
numberAddress
infoPayload FCS
2octet 1 4-20 n ≤ 102 2
2
MAC Protocol Data Unit (MPDU)
1 1octet
MAC
PHY
35KJH
MAC OverviewMAC Overview
The features of the MAC sub-layer Beacon managementChannel accessGuaranteed time slot managementFrame validationAcknowledged frame deliveryAssociation and disassociationSecurity mechanisms
FFD (Full Function Device)A device capable of operating as a coordinator or device, implementing the complete protocol set.
RFD (Reduced Function Device)A device operating with a minimal implementation of the IEEE 802.15.4 protocol.
36KJH
Star / PearStar / Pear--toto--Pear TopologyPear Topology
Pear to Pear topology
ex) Cluster Tree Network
Star topology PAN coordinator
Cluster Head (CLH)
Full Function Device (FFD)
Reduced Function Device (RFD)
37KJH
SuperframeSuperframe
The LR-WPAN standard allows the optional use of a superframe structure. bounded by network beaconsdivided into 16 equally sized slots. Channel access mechanism
Beacon enabled networkslotted CSMA-CA
A non beacon enabled networkUn-slotted CSMA-CA TDD
Contention Free PeriodContention Access Period
Frame Becon
Contention access period (CAP)a slotted CSMA-CA mechanismtransactions shall be completed by the time of the next network beacon.
Contention free period (CFP)Included The guaranteed time slots (GTSs)The PAN coordinator may allocate up to seven of these GTSs
38KJH
IEEE 802.11 Wireless LANIEEE 802.11 Wireless LAN
IEEE 802.15 Wireless PANIEEE 802.15 Wireless PAN
Fast EthernetFast Ethernet
IEEE 1394IEEE 1394
QoSQoS guaranteed technology in Home guaranteed technology in Home networksnetworks
39KJH
Fast Ethernet(100BASEFast Ethernet(100BASE--T) Std.T) Std.
IEEE 802.3 WG History
UTP cable, NIC-HUB: 100m, star1995100Base-VG802.311
100Base-TX : UTP cable, NIC-Hub : 100m , star
100Base-FX : Fiber optic cable, star1995.6.14100Mbps Standard, MII, PHY and MAUs802.3u
1995.6.14Informative Annex to 10Base-T for 120Ω
cabling802.3t
1993.6.17GDMO formating of Layer Management for
10Mbps DTEs802.3q
1993.6.17Management for 10Mbps Integrated MAUs802.3p1992.9.27PICS perform for 10Mbps UTP MAU802.3l1992.9.17Layer management for 10Mbpsrepeater802.3k
10Base-FP, FB&FL, Fiber Cable, Point-to-Point Connection (2km)
1993.9.1510Mbps Fiber Optic MAUs802.3j
10Base-T, UTP cable, Hub usb, NIC-Hub : 100m, star
1990.9.2810Mbps UTP MAUs802.3i
1990.9.28Layer Management for 10Mbps DTEs802.3h
1Base5, UTP cable, Manchester code, Star-LAN, 100m/2.5km
1987.6.111Mbps "starLAN" MAU802.3e
Fiber Inter-Repeater Link1987.12.110Mbps FOIRL MAU802.3d1986.3.13Broadband repeater802.3c
10Base36, 75Ω Coax Cable, Bus1985.9.1910Mbps Broadband MAU802.3b10Base2, 50ΩCoax Cable (thick), Bus1985.6.1310Mbps Cheapernet MAU802.3a10Base5, 50ΩCoax Cable (thick), Bus1983.6.2410Mbps MAC, PLS, AUI802.3
FeatureYearTitleIEEE
40KJH
Ethernet OverviewEthernet Overview
IEEE 802.3x(100BaseX)No QoS support
100BaseX FeaturePhysical Topology : STARLogical Topology : Linear BUSAccess Method : CSMA/CDDate Rate : 100MbpsSignal Transmission mode : Baseband
100VG-AnyLANIEEE 802.12 Std. : proposed HP, AT&TQoS support
100BaseVG FeaturePhysical Topology : StarLogicak Topology : Star/BusAccess Method : Demand Priority mode Support Ethernet and Token-RingDate Rate : 100MbpsSignal Transmission mode : Baseband
41KJH
Ethernet MAC FrameEthernet MAC Frame
Preamble
(7)
SFD
(1)
Destination
Address(6)
Source
Address(6)Length Information
LLC Header LLC information field
DSAP SSAP CTRL IP/X.25/….
DSAP SSAP CTRL OUI PID IP/X.25/…
LLC
SNAP
Max Frame Lengh 1518bytes, Min Frame Length 64bytes
1 0 local Address
1 1 Global Address
0 Individual AddressLSB
Multicast
Address
1111….1111: broadcast Address
FCS=Frame Check SequenceSFD=Starting Frame DelimiterLLC=Logical Link ControlPID=Protocol IdentifierOUI=Organizationally Unique IdentifierSNAP=Sub Network Access ProtocolCTRL=Control field
SSAP=Source Service Access PointDSAP=Destination Service Access Point
pad FCS (4)
42KJH
IEEE 802.1p and IEEE 802.1QIEEE 802.1p and IEEE 802.1Q
802.1D (the spanning tree standard)Traffic forwarding(bridge), multicast frames(port)
No mechanism for the switch to determine(multicast)
802.1pExtension from 802.1D to allow for more intelligent handling of multicast frames.
Directly attached or further downsteam that needs to receive the multicast frame(dynamic)
Safety, speedly time-critical information forwarding
802.1Qexentended 802.1p
Definition and management of vLAN(set)
43KJH
IEEE 802.1p/ IEEE 802.1Q IEEE 802.1p/ IEEE 802.1Q Priority LevelPriority Level
IEEE 802.1p establishes 8 levels of priority.Network managers must determine actual mappings
The highest priority is seven, which might go to network-critical traffic
Routing Information Protocol (RIP), Open Shortest Path First (OSPF) table updates.
Values five and six might be for delay-sensitive applications
interactive video, voice.
Data classes four through one range from controlled-load applications
Streaming multimedia, business-critical traffic - carrying SAP data
The zero value is used as a best-effort default
44KJH
IEEE 802.1p: LAN Layer 2 IEEE 802.1p: LAN Layer 2 QoS/CoSQoS/CoSProtocol for Traffic Prioritization Protocol for Traffic Prioritization
Prioritize traffic The prioritization specification works at the MAC framing layer
Perform dynamic multicast filtering.Filter multicast traffic to ensure it does not proliferate over layer 2-switched networks.
Defined as best-effort QoS or CoS (Class of Service) at Layer 2
Implemented in network adapters and switches without involving any reservation setup.
No bandwidth reservations are established. 802.1p traffic is simply classified and sent to the destination
45KJH
IEEE 802.1p/ IEEE 802.1Q IEEE 802.1p/ IEEE 802.1Q MAC Frame FormatMAC Frame Format
Tag Protocol ID(TPID)defined value of 8100 in hex. When a frame has the EtherType equal to 8100, this frame carries the tag IEEE 802.1Q / 802.1P.
Tag Control Information (TCI)User Priority
eight priority levels.
Canonical Format Indicator (CFI)used for compatibility reason between Ethernet type network and Token Ring type network.
VLAN ID (VID)VLAN ID is the identification of the VLAN, which is basically used by the standard 802.1Q.
maximum possible VLAN configurations are 4,094.
VID of 0 – used to identify priority frames
VID of 4095 – reserved value
User PriorityUser Priority
(3bits)(3bits)
CFI
(1bit)
Bits of VLAN ID to identify possible VLANs
(12bits)
Preamble
(7)
SFD
(1)DA (6) SA (6)
TPID
(2)
TCI
(2)
Type
Length
(2)
Data
(42-1496)
FCS
(4)
46KJH
IEEE 802.11 Wireless LANIEEE 802.11 Wireless LAN
IEEE 802.15 Wireless PANIEEE 802.15 Wireless PAN
Fast EthernetFast Ethernet
IEEE 1394IEEE 1394
QoSQoS guaranteed technology in Home guaranteed technology in Home networksnetworks
47KJH
IEEE 1394 StandardsIEEE 1394 Standards
IEEE 1394 : 1995Supports up to 400Mbps links and PHYs6 pin cablesRange : 4.3m
IEEE 1394a : 2000Supports up to 400Mbps links and PHYsPower management clean upCable power specification in flux
IEEE 1394 OHCI(Open Host Controller Interface)IEEE 1394b : 2002
Supports up to 3.2GbpsRange : 100m
IEEE 1394.1(Bridging)IEEE 1394.3(Peer-to-Peer Printing)IEEE 1394 over wireless
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IEEE 1394 OverviewIEEE 1394 Overview
Logical bus model
Peer-to-peer operation
User friendly Ease of Use - Plug and Play
Transaction and addressing models
Asynchronous and Isochronous operation models (QOS)
Power management (with one new mode)
“Daisy chaining” of devices
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IEEE 1394 Network ArchitectureIEEE 1394 Network Architecture
B
B
BusBus
Bus
B :Bridge(max 1023)
:Node(max 63/bus)
:Cable(4.5m)
IEEE 1394 network architecture(bus and bridge)
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IEEE 1394 TopologyIEEE 1394 Topology
The 1394 protocol is a peer-to-peer network with a point-to-point signaling environment
A specific host isn’t required
Nodes on the bus may have several ports on them
Desktop
camera
Laser
printer
Digital
TV
Set-top
box
Digital
VTR
Bridge
CPU Memory I/O CPU
Serial bus(backplane environment)
IEEE 1394 serial bus (cable environment)
Nodes
Nodes
Ports
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IEEE 1394 Protocol StacksIEEE 1394 Protocol Stacks
Serial Soft API
Bus mgr
SynchronousResource mgr
Node controller
Transaction Layer
(Read/write asynchronous data)
Link Layer
(Cycle control, Packet function)
Physical Layer
(Bus initialization and arbitration, synchronization, coding and signaling)
IEEE 1394 physical interface
Configuration & Error control
Channel assignments for media flows
Isochronous channel
Packets
Read,Write,Lock
Symbols
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IEEE 1394 Protocol ModelIEEE 1394 Protocol Model
Packets created at the link level of arbitrary size
Transaction-level protocol Handles writings and reading of asynchronous data
Link-level protocol Distributes a timing and synchronization “cycle control” signal
Synchronous resource manager Allocates time slots to devices with periodic data to send
Bus manager power management and bus optimization
Contention for management roles occurs during initialization with selections made according to device numbering or random selection criteria
53KJH
IEEE 1394 Physical LayerIEEE 1394 Physical Layer
The Physical layer provides initialization and arbitration services
It assures that only one node is sending data at a time
The physical layer of the 1394 protocol includes:The electrical signaling
The mechanical connectors and cabling
The arbitration mechanisms
The serial coding and decoding of the data being transferred or received
Transfer speed detection
54KJH
IEEE 1394 Link LayerIEEE 1394 Link Layer
Gets data packets on and off the wire
Error detection and correction
Retransmission
Handles provision of cycle control for isochronous channels
The link layer supplies an acknowledged datagram to the transaction layer
A datagram is a one-way data transfer with request
confirmation
55KJH
IEEE 1394 Transaction LayerIEEE 1394 Transaction Layer
Implements the request-response protocol
ReadData is transferred back to a responder
WriteData is transferred from a requester to an address within one ormore responders
LockData is transferred from a requester to a responder, processed with data at a particular address within the responder, and thentransferred back to the requester
56KJH
Isochronous TransmissionIsochronous Transmission
Isochronous transfersIsochronous transfers are always broadcast
No error correction and retransmission
Up to 80% of the available bus bandwidth can be used
The delegation of bandwidth is tracked by a node on the bus
Isochronous channel IDs are transmitted followed by the packet data
The receiver monitors the incoming data's channel ID and accepts only data with the specified ID
57KJH
Asynchronous TransmissionAsynchronous Transmission
Asynchronous transfersAsynchronous transfers are targeted to a specific node with an explicit address
Not guaranteed a specific amount of bandwidth on the bus
They are guaranteed a fair shot at gaining access to the bus when asynchronous transfers are permitted
Asynchronous transfers are acknowledged and responded to
This allows error-checking and retransmission mechanisms to take place
58KJH
ArbitrationArbitration
Sources of isochronous flows send requests for channel number and time slots to the synchronous resource manager
Each 125 μsec cycle : one-byte time slotsE.g. 6250 slots at 400Mbps
First-come first-served
Asynchronous traffic : 20% of time slots
Isochronous traffic : 80% of time slots
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IEEE 1394 Time Slot AssignmentsIEEE 1394 Time Slot Assignments
Ch B Ch C Ch D Ch ECycle
StartCh B Ch C Ch D
Cycle
StartCh B
Cycle
Start
Packet
B
Nominal cycle period = 125 us Nominal cycle period = 125 us
DelayCycle n Cycle n+1
Cycle S
ync
Cycle S
ync
Cycle S
ync
AC
K
Delay
Packet
B
AC
KCh D
: Isochronous Transactions : Asynchronous Transactions
: Cycle starts Packets
Subaction (long) Gaps Subaction (long) Gaps Subaction (long) Gaps
Assigned channel numbers and allocated time slots
Isochronous (short) gaps Isochronous (short) gaps
One byte time slots
60KJH
Bridging IEEE 1394 networksBridging IEEE 1394 networks
1394 bridge device1394 device
1394 application1394 Tr.
1394 Link1394 PHY
Asynch. Isoch.
1394 mngmnt & internal fabric1394 Tr. 1394 Tr.
1394 Link1394 PHY
1394 Link1394 PHY
Isoch. Isoch.Asynch. Asynch.
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IEEE 1394 to a wireless air interfaceIEEE 1394 to a wireless air interface
Wireless 1394 bridge deviceWireless 1394 device
1394 application1394 Tr.
Asynch. Isoch.
1394 mngmnt & internal fabric1394 Tr. 1394 Tr.
1394 Link1394 PHY
Isoch. Isoch.Asynch. Asynch.
1394.1 CLWireless DLCWireless PHY
1394.1 CLWireless DLCWireless PHY
CL : Convergence layer, DLC : Data Link Control
62KJH
Protocol stack for the HDNI serial busProtocol stack for the HDNI serial bus
Reference
[8] “Engineering Committee, Digital Video Subcommitee,” American Natinal Standard(Home Digital Network Interface Specification), ANSI/SCTE, 26, 2001
1394 Physical
1394 Link
1394 Transaction
FCP
61883 – CIP
DVCR
(61883)
MPEG
(61883)
Other
(61883)
Application Data Channel
OSD
FCP
IP
UDP or
TCP
Application,
AV/C,etc
HTML,
JavaScript,
Etc.
Isochronous Asynchronous
DVCR : Digital Video
Cassette recorder
OSD : On-Screen
Display
AV/C : Audio Video
Control
MPEG : Motion Picture
Experts Group
CIP : Common
Isochronous Packet
FCP : (Function Control
Protocol
63KJH
IEEE 802.11 Wireless LANIEEE 802.11 Wireless LAN
IEEE 802.15 Wireless PANIEEE 802.15 Wireless PAN
Fast EthernetFast Ethernet
IEEE 1394IEEE 1394
QoSQoS guaranteed technology in Home guaranteed technology in Home networksnetworks
64KJH
Quality of Service BasicsQuality of Service Basics
DefinitionA collective measure of the level of service delivered to the customer
QoS basic performance criteria Error performance, response time and throughput
Lost calls or transmissions due to network congestion
Connection set-up time, speed of fault detection and correction
For the transmission of time sensitive information over a network
Bandwidth
Latency
Jitter
Packet Error Rate
65KJH
QoSQoS Requirements by Service TypeRequirements by Service Type
0>100>1000.5Low Speed Data
0>100>1002Medium Speed Data
0>100>10010High Speed Data
10-5101000.256CD Quality Audio
10-510903SDTV
10-5109019.68HDTV
10-55101.5 X 2 streamsVideo Conference
10-320300.008 X 2 streamsMedium Quality Voice
10-35 100.064 X 2 streamsHigh Quality Voice
PERJitter
(ms)
Latency
(ms)
Payload Rate
(Mbps)
Service
±±±±±
Reference
[10] L. Chinitz, “Quality of Service in the Home Networking Model,” Home RF working group, Aug., 2001.
66KJH
Data Rates Supported by Multiple Data Rates Supported by Multiple TechnologiesTechnologies
1 MbpsHomeRF
1 MbpsHomePlug
10 MbpsHomePNA 2.0
54 MbpsHiperLAN2
11 MbpsIEEE 802.11b
54 MbpsIEEE 802.11a
100 MbpsFast Ethernet
12 MbpsUSB 1.1
480 MbpsUSB 2.0
400 MbpsIEEE 1394a
800 MbpsIEEE 1394b
SpeedInterconnectivity
Technology
67KJH
Two Two QoSQoS Support Categories Support Categories
Priority(Differentiated) based QoS
Parameter(Scheduled) based QoS
PSTN
xDSL
Cable Modem (DOCSIS v.1.1)
FTTH
Cable Home 1.1Last Mile
Access
IEEE 802.1P/Q
IEEE 802.3
IEEE 802.11e [HCCA]
IEEE 1394
IEEE 802.15.3
IEEE 802.11e QoS [EDCA]
HomePNA
HomePlug
Per-flow state and signaling at every hopsDifferentiated QueuesForwarding
/Queuing
Planed opportunitiesDifferentiated Access
Media Access
ParameterPriority
Media Access : Access the shared media
Packet Forwarding : Packets forward in home gateways, routers or bridges
68KJH
Application of a PrioritiesApplication of a Priorities--BasedBasedQoSQoS SystemSystem
Cable
Head End
CRGD
O
C
S
I
S
PS
BP QBP
CQP
Apps/EP
BPApps/EP
BP
Apps/EP
BP
Network
Segment
Network
Segment
QBP QBP
QBP
Home
Network
Cable
Network
Apps
Q-Domain
Example of cable QoS elements (Adapted from ITU-T J.190)
CH CH
CH
CableHome QoS Portal (CQP): QoS Sub-Element of the PSPriorities-QoS queuing/forwarding
Responsible for communication of QoS characteristics to various devices
QoS Boundary Point (QBP): QoS Sub-Element of the BPResponsible for the reception of QoS characteristics information from PS
CRG : Cablehome Residential Gateway, CH : CableHome host, BP : Boundary Point, PS : Portal Service
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The elements for providing The elements for providing QoSQoSin in CableHomeCableHome networknetwork
PS forwardingPrioritized queuing and packet forwarding functionality in the
CQP.
PS media accessPrioritized shared media access functionality in the CQP.
QoS management serverMaintain QoS priority
BP media accessPrioritized shared media access functionality in the QBP.
QoS management clientDetermines QoS characteristics that a particular application/device needs to use
70KJH
WiFiWiFi QoSQoS Access Timing ExampleAccess Timing Example
AssumptionsWME default parameters backoff values shown are for initial CW equal to CWmin = 15
2Slots 0~3 Slots
2Slots 0~7 Slots
3Slots 0~15 Slots
7 Slots 0~15 Slots
AIFS
AIFS
AIFS
AIFS
Minimum Wait Random Backoff Wait
Voice
Video
Best Effort
Background
Previous
packet N Slots 0~m SlotsNext
packet
SIFSMinimum Wait Random Backoff Wait
Host Host
Host
Host
Host
Residential
Gateway
Media Access
71KJH
WiFiWiFi QoSQoS Packet Forwarding QueuesPacket Forwarding Queues
Four Access Categories are actually 4 independent queues in the client
Host Host
Host
Host
Host
Residential
Gateway
Packet
Forwarding
Air
Four Transmit Queues
Voice
Data
Video
Data
Best Effort
Data
Background
DataMapping to Access Category(AC)
72KJH
ParemeterParemeter--Based Based QoSQoS Guaranteed Guaranteed TechnologyTechnology
HomePNA IEEE 1394 Ethernet WLAN
UWBWDM ZigbeeDOCSISxDSL
Generic Middware
ClassifierQueue
manager
Bridge
manager
Bandwidth
manager
UPnP Jini HAVi Echonet IPHN
Conversation Streaming Interactive Background
Linux Solaris Windows CE
HomePNA
PHY
MAC
Middleware
Application
Real-time OS
QoSsupport
QoSsupport
73KJH
The elements of The elements of QoSQoS ManagerManager
The elements of QoS ManagerClassifier
Identify different categories of packets coming from different network interfacesClassify packet into various classes
Queue managerEfficient and fair allocation of buffer resources
Bridge managerSupport priority-based routing and load balancing
Bandwidth managerAllocate system bandwidth efficiently and fairly among all stations sharing each physical medium
Channel monitorTrack of the Quality of a channel
Port schedulerPolicy-based channel-dependent scheduler
74KJH
QoSQoS issues in Home Networksissues in Home Networks
Different kinds of QoS protocol in Home networksTransmission rate, QoS parametersPacket format, Traffic characterized various priority
PHY LayerWireless channel environment QoS supported devices or no supported devices
MAC LayerVarious QoS supported protocol
MiddlewareExist many different kinds of middleware such as UPnP, HAVi, Jini etc
Network LayerIP based or non IP based protocols
OSSupport Real-time OS or not
GQoS API (802.1p priorities or RSVP parameters) is requested through Winsock2Linux Kernel 2.4.14 and above with skb-priority using the vconfigutility
75KJH
Research ScopeResearch Scope
First of all, Need the QoS definition
Survey the more detailed information of existing QoS guaranteed technologies in Home networks
Seek for the problem of the process that multimedia input streams come to good output streams in Home networks
Need unified QoS parameter mapping structure
76KJH
ReferenceReference
[1] “Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) specifications :Higher-Speed Physical Layer Extension in the 2.4 GHz Band”, IEEE Std 802.11b-1999, 1999
[2] “Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) specifications Amendment 4: Further Higher Data Rate Extension in the 2.4 GHz Band”, IEEE Std 802.11g.-2003, 2003
[3] “Part 15.1: Wireless Medium Access Control (MAC) and Physical Layer (PHY) Specifications for Wireless Personal Area Networks (WPANs)”, IEEE Std 802.15.1™-2002, 2002
[4] “Specification of the Bluetooth System”, BLUETOOTH SPECIFICATION Version 1.1, Feb. 2001
[5] http://www.ieee802.org/15/pub/TG2.html
[6] “Part 15.3: Wireless Medium Access Control (MAC) and Physical Layer (PHY) Specifications for High Rate Wireless Personal Area Networks (WPAN)”, Draft P802.15.3/D17, Feb. 2003
[7] “Part 15.4: Wireless Medium Access Control (MAC) and Physical Layer (PHY) Specifications for Low-Rate Wireless Personal Area Networks (LR-WPANs)”, IEEE Std 802.15.4™-2003, 2003
[8] “Engineering Committee, Digital Video Subcommitee,” American Natinal Standard(Home Digital Network Interface Specification), ANSI/SCTE, 26, 2001
[9] M. Nakagawa, “Ubiquitous Homelinks Based on IEEE 1394 and Ultra Wideband Solutions,” IEEE Communications Magazine, pp. 74-82, Apr., 2003.
[10] L. Chinitz, “Quality of Service in the Home Networking Model,” Home RF working group, Aug., 2001.
[11] S. Weinstein, “Integrated networking,” ELE6905, Spr., 2004.
[12] http://www.commsdesign.com/showArticle.jhtml?articleID=18100157