1
June 2009
John Moring
Overview
IEEE 1609.0, 1609.3,
1609.4, 1609.5
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Contents
Standards Overview
IEEE P802.11p WAVE MAC and PHY
IEEE 1609.4 Multi-Channel Operation
IEEE 1609.3 Networking Services
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WAVE Scope
OBU
WA
VE
Sta
ck
Wir
elin
e S
tack
In Vehicle Network
OBU
WA
VE
Sta
ck
Wir
elin
e S
tack
In Vehicle Network
Applications
Optional External Interface
Air Interface
WA
VE
Sta
ck
Applications
WA
VE
Sta
ck
Optional External Interface
Host
Wir
elin
e S
tack
Host
Wir
elin
e S
tack
Host
Wir
elin
e S
tack
Host
Wir
elin
e S
tack
Covered by WAVE StandardsROAD SIDE
UNIT
ON-BOARD UNITS
External Systems
External Systems
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Protocol Architecture
UDP / TCP
LLC
PHY
WAVE MAC (including channel coordination)
Air
In
terf
ace
IPv6WSMP
Data PlaneManagement Plane
Ma
nag
em
ent
Se
curit
y
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Trial Use Standards
IEEE Std 1609.1-2006
• Resource Manager
IEEE Std 1609.2-2006
• Security Services
IEEE Std 1609.3-2007
• Networking Services
IEEE Std 1609.4-2006
• Multi-Channel Operation
IEEE P802.11p - draft
• WAVE MAC and PHY
IEEE Std 802.11-1999
• MAC and PHY
Lower Layers
Networking Services
Upper LayersWAVE Service Security
IEEE 1609.1, et al.
IEEE 1609.3
IEEE 1609.4, IEEE 802.11p
WAVE device
Medium
IEEE 1609.2
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Full Use Standards in process
UDP / TCP
LLC
PHY
WAVE MAC (including channel coordination)
IPv6WSMP
1609
.3
1609.2M
anag
emen
t
Sec
urity
1609
.4
802.
11
Fut
ure
high
er
laye
r st
anda
rds
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Ongoing Standards Activities
IEEE P802.11p work continues
Full Use 1609 updates in process
• 1609.2, 1609.3, 1609.4
Resource Manager standard being redefined to address low-end devices
• 1609.1
Architecture document in process
• 1609.0
Communications Manager standard authorized
• 1609.5; placeholder for possible future work
Electronic payment services standard in process
• 1609.11
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Overview of 802.11p (D7.0)
Specifies channelization in the 5.9 GHz band
Tunes some RF specs to allow highway operation
Defines a mode of operation “outside the context of a basic service set”
• Removes latency-causing link setup operations such as authentication
Defines a Time Advertisement message
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Overview of 1609.4 Multi-Channel Operation
Extensions to the 802.11/802.11p MAC
Management plane (MLME: MAC SubLayer Management Entity)
• Manages optional regular switching between control channel and service channel
• Queues regular time advertisements and/or service advertisements
Data plane (MAC)
• Multiplexes/demultiplexes higher layer protocols (IPv6, WSMP)
• Queues messages for transmission on the correct channels
• Manages transmit message priority
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1609 Channel Coordination examples
CCH
CCH
SCH
CCH Interval SCH IntervalCCH IntervalSCH Interval
Time
a)
b)
CCH
SCH
c)
CCH
SCH
d)
Continuous access
Alternating access
Immediate access
Extended access
Control Channel: management and (high priority) messages
Service Channel: general user message and IP traffic
For devices that don’t need continuous CCH access
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1609.4 Transmit Operation
MAC (with Muti-Channel Operation)
Transmission Attempt
Channel Selector and Medium Contention
Internal Contention
AIF
S[A
C]
CW
[AC
]T
XO
P[A
C]
AIF
S[A
C]
CW
[AC
]T
XO
P[A
C]
AIF
S[A
C]
CW
[AC
]T
XO
P[A
C]
AIF
S[A
C]
CW
[AC
]T
XO
P[A
C]
Internal Contention
AIF
S[A
C]
CW
[AC
]T
XO
P[A
C]
AIF
S[A
C]
CW
[AC
]T
XO
P[A
C]
AIF
S[A
C]
CW
[AC
]T
XO
P[A
C]
AIF
S[A
C]
CW
[AC
]T
XO
P[A
C]
CCH (WSM data only) SCH (WSM and/or IP data)
LLC
Channel Routing
802.
11p
MA
C (
CC
H)
802.
11p
MA
C (
SC
H)
Management frames
Management frames
AC=1 AC=2 AC=3 AC=4 AC=1 AC=2 AC=4AC=3
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Overview of 1609.3 Networking Services
Management plane (WME: WAVE Management Entity)
• Generates contents of service advertisements based on higher layer info
• Including IP configuration info and security credentials
• Monitors received service advertisements for services of interest to higher layers
• Estimates channel quality
• Determines channel allocation/switching schedule to satisfy service requests
Data plane
• Incorporates standard LLC and IPv6
• Introduces thin WAVE Short Message Protocol (WSMP)
• Allows direct control of RF parameters (e.g., power, data rate) by the higher layer
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WAVE Short Message Protocol (WSMP)
Messages transmitted on request by higher layer
• Dest. MAC address, User Priority, Channel, Data rate, Transmit Power, PSID
Messages delivered over the air by MAC address
• Unicast or broadcast
Messages delivered up the stack by protocol and PSID
• EtherType distinguishes WSMP from IP
WSM data
WSMP version
PSIDWSM length
Higher layer
WSMP
LLC
MAC
WSM data
Control= 0x03
WSM data
WSMP HeaderEtherType =0x88DC
DSAP= 0xAA
SSAP= 0xAA
Channel number
Data rate
TxPwr_Level
PSID Length
PriorityDest_
address
OUI=0x000000
PriorityDest
address
Peer MAC
address
User priority
WME-Wave ShortMessage.req
DL-UNITDATA.req
MA-UNITDATA.req
SNAP headerLLC header
Data field
WSM element
ID
Ext. fields
Channel number
Data rate
TxPwr_Level
Channel number
Data rate
TxPwr_Level
Expiry Time
Expiry Time
Expiry Time
1 2311
1 21Var.4 Var.
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“Services”
Provider role
• Sends out WAVE Service Advertisements (WSAs) on control channel• Includes info on services and channels
• May include IP configuration info
• In Trial Use, included timing info – now separate
• Operates on identified service channel(s) at designated times for application data exchange
User role
• Monitors WSAs for services of interest
• May visit identified service channels at designated times for application data exchange
Allocation of radio resources to communication channels performed by 1609 stack based on higher layer request priority, service availability, device capabilities
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WAVE Service Advertisement (WSA) contents
Channel InfoService Info
4 1 1 1 1 1
Channel Number
Adapt-able
Data Rate
TxPwr_Level
2 16 1 16 16
1
May be repeated
May be repeated
11
6
1Var.1
PSIDService Priority
Channel Number
Router lifetime
IpPrefixPrefix length
Default gateway
Primary DNS
Gateway MAC
address
Provider Service Table WAVE Routing Advertisement WAVE version
Extension fieldsRepeats
Extension fields
Extension fields
Var.
Var.
Extension fields
Var.
KEY
Optional Field
Lengths in octets
1
WAVE Element
ID
WAVE Element
ID
1
WAVE Element
ID
Info about available services Info about service channels
IP configuration info
Transmit Power Used
2D/3D Location
Advertiser Identifier
PSC
IPv6 Address
Service Port
Provider MAC Address
Secondary DNS
EDCA Parameter Set
KEYKEY
Extension fields
Optional
Lengths in octets
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Example of WAVE Transmit Protocol Layers
MLME
PHY Header
MAC Header
MAC Trailer
WSA
PHY
Security Header
WaveService AdvertisementSecurity Trailer
WSA Header
PST WRA
WME
Security Services
WME
Vendor Specific Action frame
Air interface
MAC
Vendor Specific Content
SEC-SignWSA.req
WME-ProviderService.req
SEC-SignWSA.cfm
MLMEX-WSA.req
Higher layer
Service info
MLME extension
WSAMLME-VSPECIFIC.reqOUI
Cont-ent
descr.
Category
OUI
This illustrates content from the higher layers, processed by the WAVE stack, and sent out as a service advertisement in an 802.11 frame
IEEE 1609
IEEE 802.11
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WSA Flow, allows devices to coordinate SCH usage for data exchange
UserProvider
MLME MLMEHigher layer
Higher layer
SECURITY WMEWME SECURITY
MLMEX-WSA.req
MLMEX-WSA.ind
MLMEX-WSA.cfm
WSA
MLMEX-SCHSTART.cfm
MLMEX-SCHSTART.req
MLMEX-REGISTERTXPROFILE.req
MLMEX-REGISTERTXPROFILE.cfm
MLMEX-WSA.rsp
MLMEX-REGISTERTXPROFILE.req
MLMEX-REGISTERTXPROFILE.cfm
Sent if service uses IP
Decide to assign channel
access
Decide to assign channel access
Service request processing
Service request processing
SEC-SignWSA.req
SEC-SignWSA.cfm
MLMEX-SCHSTART.req
MLMEX-SCHSTART.cfm
SEC-VerifyWSA.cfm
SEC-VerifyWSA.req
Data exchange
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PSID & PSC
Provider Service Identifier (PSID)
• 4 octets; values allocated by IEEE
• Used as WSMP recipient address, and
• Used as primary identifier of services in WAVE Service Advertisement
• Presumably identifies type of information and encoding to be found on the SCH
Provider Service Context (PSC)
• 0-32 octets; meaning determined by PSID
• Used as optional secondary service descriptor in WSA
• May indicate information sub-type, date tag, security context, etc.
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Going Forward
Core WAVE standards: 802.11p, 1609.4, 1609.3, 1609.0
• Expect technical work to finalize this year
• Standards published by mid-2010
Work on other standards proceeding