1. doc.: IEEE 802.15-<doc#>
<month year>
doc.: IEEE <doc#>
Project: IEEE P Working Group for Wireless Personal Area Networks (WPANs)
Submission Title: TG8 PAC Link Layer Specification
Date Submitted: 18 July, 2013
Source: Seong-Soon Joo, Jong-Arm Jun, In-Hwan Lee, Cheol-Sig Pyo
Company: ETRI
Address: 161 Gajeong-dong, Yuseong-gu, Daejeon, KOREA
Voice: , FAX: ,
Re:
Abstract: As a final proposal for the IEEE TG8 standards, the reference model of the PAC enabled networks and the PAC link layer specification are proposed.
Purpose: Response to the IEEE TG8 call for proposal
Notice: This document has been prepared to assist the IEEE P It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein.
Release: The contributor acknowledges and accepts that this contribution becomes the property of IEEE and may be made publicly available by P
<author>, <company>

2. TG8 PAC Link Layer Specification
<month year>
doc.: IEEE <doc#>
TG8 PAC Link Layer Specification
Seong-Soon Joo*,
Jong-Arm Jun, In-Hwan Lee, Cheol-Sig Pyo
ETRI
<author>, <company>

3. Concepts and Architecture (I)
peer-to-peer wireless personal area network
The network in which a device can act as a client or server for the other device by allowing shared access of various resources such as configuration or control information, location information, sensing data, advertisement, multi-media contents, social contents, etc.
PAC WPAN 1
HPD
GPD
PAC WPAN 2
HPD
GPD

4. Concepts and Architecture (II)
networks with the PAC enabled devices
networks of the PAC enabled devices only
PAC WPAN
networks of the devices equipped with the PAC
PAC enabled X-network (e.g. LTE, Ethernet, WiFi, … )
hybrid networks of the PAC WPAN and the PAC enabled X-networks
hybrid PAC network
PAC enabled device
X-network device
PAC WPAN
PAC enabled X-network
Hybrid PAC Network

5. proxy host of P2P network
Topology (I)
peer network host (proxy host)
define a mission, configure the peer group, host peers, authenticate peers, get a service
peer network guest
authenticate the host, serve to the peer group
peer network relay
relay the frame from the host or the frame from the guest
observer of the peer network
not a member of peer group, listen the peer network
wireless device6
wireless device1
wireless device5
wireless device4
wireless device2
wireless device3
host of P2P network
space A
proxy host of P2P network
guest of P2P network
relay of P2P network
observer of P2P network
space A
P2P network 1
wireless device1
P2P network 3
thing 1
wireless device6
wireless device2
thing 6
thing 2
wireless device5
wireless device3
thing 5
thing 3
wireless device4
P2P network 2
thing 4

6. Topology (II)
possible network configurations with the PAC enabled networks
one PAC WPAN
multiple PAC WPAN
one PAC WPAN & one X-network
one PAC WPAN & multiple X-network
multiple PAC WPAN & one X-network
multiple PAC WPAN & multiple X-network
X-network 1
X-network 1
X-network 1
X-network 2
PAC WPAN 1
PAC WPAN 1
PAC WPAN 2
PAC WPAN 1
PAC WPAN 1
PAC WPAN 1
PAC WPAN 2

7. Reference Model components of PAC enabled device entity SAP
3 link sub-layer entities
1 management entity
SAP
2 SAPs for the higher layer of PAC device
1 SAPs for PAC enabled external-network device
Link
Application
PHY
Network
PD Management Entity
IEEE Link Network sublayer
PAC Service Adaptation Sublayer
IEEE Medium Access Control sublayer
IEEE Link Control sublayer
IEEE PHY
PHY-SAP
LINK-SAP
EXTMANG-SAP
PDMANG-SAP
External Device Management
Entity
IEEE Link layer
PAC enabled external-network device
PAC device

8. Addressing of Peer Networks
peer network ID
service class of peer network
service priority of a peer network
peer network service profile identifier
identify the service offered by a peer network
need registry
local peer network identifier
identify a peer network among peer networks in a proximity which provide the same service
Bits: 2 10 4
Service Class of Peer Network
Peer Network Service Profile Identifier
Local Peer Network Identifier

9. Local Peer Device Identifier
Addressing of Devices
device ID
global device identifier : 64bit
local device identifier : 16bit
group identifier
0x0 : local device identifier in a peer network
0xf : broadcast in a peer network
local peer device identifier
unique identifier in a peer network
generated by hashing based on global device identifier, peer network service profile identifier, capability of device
reserved local peer device identifier
0x000 : host of a peer network
0x001 : proxy host of a peer network
0xfff : broadcast or groupcast
device identification in proximity
network ID + group ID + local device ID
one device can have multiple peer IDs
Bits: 4 12
Group Identifier
Local Peer Device Identifier

10. Peer Network Device Profile
peer device may have multiple peer network device address per each peer network
device capability
service capability
master clock, host, proxy host, relay
dedicated control channel PHY, always on receiver PHY
main powered
security
list of capable service profile
Bit 0 1 2 3 4 5 6 7
Master Clock Capable
Proxy Host Capable
Peer Relay Capable
Main Powered
Security Capable
Dedicated Control Channel
Always On Receiver
Reserved

11. Device Advertisement Frame
advertise periodically by transmitting peer advertisement frame
Octet: 1 1
variable
Peer Network Information Element Type
Peer Network Information Element Length
Device Capability Descriptor
Device Service Descriptor
Service Profile List
Joined Peer Network List
Neighbor Relation
List
Bits: 2 3
Number of Capable Service
Number of Joined Network
Number of Joined Group
Bit 0 1 2 3 4 5 6 7
Master Clock Capable
Proxy Host Capable
Peer Relay Capable
Main Powered
Security Capable
Dedicated Control Channel
Always On Receiver
Reserved

12. MPDU Structure (I) link frame type link frame header
pre-network formation, after-network formation
control frame, data frame, broadcast frame in proximity
link frame header
frame control : version, type, length
peer network identifier : service type, network profile
address
peer network authenticator
link frame information
type, length, value
peer network information element : for synchronization, network formation, discovery
link frame payload
link frame tail
frame check sequence
Octets: 2 2
0/2/8
variable
Frame Control
Peer Network Identifier
Destination Address
Source Address
Peer Network Authenticator
Peer Network Information Element
Frame Payload
Frame Check Sequence
Peer Network Addressing fields
Link Frame Header
Link Frame Infromaiton
Link Frame Payload
Link Frame Tail

13. MPDU Structure (II) frame control peer network identifier
frame version (3 bits) :
frame type (3 bits) : broadcast, peer-discover, peer-network management, peer-network data
frame length (10 bits) : up to 1024
peer network identifier
peer network service class (2bits)
peer network profile identifier (10bits): peer network profile
peer network number (6bits): identical number among peer networks of same service profile
peer device address
two types of address : 64 bit address, 8 bit address assigned in a peer network
peer network authenticator
PD’s 64bit address with pre-define key

14. MPDU Structure (III) peer network information element
pre-network management information
peer network clock synchronization
peer device advertisement
peer discovery
phase descriptor
slot allocation descriptor
residual time to the end of phase or to the start of next phase
peer link connection
after-network management information
peer beacon
peer grouping
peer groupcast
peer relaying
peer link release

15. Service Class of Peer Network Peer Network Service Profile Identifier
Bits: 2 10 4
Service Class of Peer Network
Peer Network Service Profile Identifier
Local Peer Network Identifier
Bits: 4 12
Group Identifier
Local Peer Device Identifier
Octets: 2 2
0/2/8
variable
Frame Control
Peer Network Identifier
Destination Address
Source Address
Peer Network Authenticator
Peer Network Information Element
Frame Payload
Frame Check Sequence
Peer Network Addressing fields
Link Frame Header
Link Frame Infromaiton
Link Frame Payload
Link Frame Tail
Octet: 1 6
Peer Network Information Element Type
Peer Network Information Element Length
Sync Clock Time
Octet: 1 6 2 1
Peer Network Information Element Type
Peer Network Information Element Length
Timestamp
Phase Descriptor
Slot Allocation Descriptor
Residual Time
Bits: 4 4
Discover
Peer-to-Peer
Handshaking
Reserved
Bits: 4 4
Pause
Host
Guest
Relay

16. Multiple Access (I) link resources resolve contention
dependent on the PHY
how many links physically separated and working concurrently
dedicated PHY link for control channel
RF transmitters, spatial transmitters
link resources to be arbitrated
radio channel, spatial channel (3D direction based)
allocate resource in time domain
resolve contention
contention among PDs of single PAC enabled network  scheduling
contention among PDs of multiple PAC enabled networks  interference avoidance
data channel
control channel
single PHY
single PACN
multiple PHY
multiple PACN

17. Multiple Access (II) resource allocation in time domain
need a time scale for the whole components of the peer networks
synchronized scheduling possible
contention avoidance
advertise the resource allocation schedule to the neighbor PACNs
need clock synchronization source for the peer networks
resource allocation scale
unit of resource  length of time for transmitting the clock sync frame (16 bytes link frame)
length of unit timeslot  n x base timeslot
minimum sync adjust interval
sync frame burst interval
base timeslot
sync frame interval
clock sync source SF SF SF SF SF
unit timeslot
PD 1 of PACN1 AF DF
PD 2 of PACN1 AF
unit timeslot
PD 1 of PACN2 DF

18. Multiple Access (III)
configurable phases for supporting the life cycle of the P2P network
configurable resource allocation for the each phase
hosting phase
P2P phase
(a)
EOP
(b)
handshaking phase
(c)
(d)
host
guest
pause
(a)
(b)
group/guest
(c)
relay
hosting phase
P2P phase
group
host/group
handshaking phase

19. host/proxy host  guest
Multiple Access (IV)
access control
without CCA
with CCA backoff
with premium CCA backoff
assigned preemptive slot
access control on host slots
host or proxy host has a right to transmit a frame at the start of the host slot
guests contend for the host slot to transmit a frame to the host
guest performs CCA after waiting for backoff, which is determined by hashing with device address
the last portion of the host slot is reserved for communicating between host – proxy host
host and proxy host perform CCA to access the slot
host has a higher priority to the proxy host
the ratio of reserved slot portion between host tx priority and host-proxy host connection
pre specified
access control on guest slots
the first portion of the guest slot is used for contention access
the rest of the guest slot is assigned to each member of a peer network
determined by hashing with device address
base timeslot
unit timeslot
host slots
guest slots
host/proxy host  guest
host  proxy host
contention access
preemptive access

20. Starting PAC enabled Network
starting PAC device
after booting the device, listen neighbor
PDM-START-DEVICE
listen sync frame
not a host
schedule wake-up
a host
start to form a peer network
no sync frame
master clock capable & main powered device
start to transmit sync frame
start to transmit sync frame & to form a peer network
others
adjust listen interval
listen again neighbor
if can’t find clock source, fails to start device

21. adjust listen interval N
Start PD
listen network.
find sync frame ?
adjust listen interval N N Y
master clock capable & main-powered?
try maximum ?
synchronized to master clock N Y Y
device is a host ?
device is a host? N N Y N Y
schedule wakeup,
sleep
start to form a peer network
transmit sync frame
start to discover peers with sync
complete
complete
complete
complete
fail

22. Peer network service profile ID
Forming a Peer Network
peer network service profile
pre-defined specification of combined phases
get from external management entity
EXTM-PUT-SERVICE
set by the PAC service adaptation sublayer
PDM-SET-SERVICE
Peer network service profile ID
Phase Sequence
Unit timeslot
Discovery Phase
Handshaking phase
Peer data Phase
Listening Phase
Link Alloc Seq.
Duration
Pause
Host
Guest
Relay
Host Access
Guest Access 1
{D, P} 2
{h,p,g} 10
WO CCA
W CCA …
{H} 4 3

23. Moving Host & Moving Guest Networks
peer network service phases
combined peer discovery & peer-to-peer communication (handshaking phase)
peer discovery request, peer data
peer discovery response, peer data
short handshaking phase
extend when it is needed
resource allocation
no proxy-host, no relay in a peer network
no groupcast
allocate host, guest, pause
host-pause-host-pause-guest-pause
stepwise variation of pause length, when have no response

24. Moving Host & Fixed Guest Networks
peer network service phases
specification of combined phases
peer discovery – peer-to-peer data
specification of resource allocation for a phase
peer discovery phase : host – pause – guest – pause
peer-to-peer data phase : host – guest – pause – guest – host – pause
discover proxy-host at first
resource allocation
proxy-host, no relay in a peer network
no groupcast
allocate link resources to host, guest, pause

25. get peer network service profile
Start Peer Network
get peer network service profile
listen neighbor.
prepare slot reservation diagram
select start time 0 Y
start from peer handshaking ?
peering required ? N Y Y
send peer discovery frame N
send data frame with peer discovery
send peer discovery frame
receive peer discovery resp ? N N
peer discovery times up ?
receive peer discovery resp or peer data ? N
receive peer discovery resp ? Y N
send peering response frame Y Y Y
fail
complete
complete
complete

26. Peer Discovery (I) peer discovery peer discovery procedure
listen device advertisement frame
send peer discovery request frame
peer network service profile
peer network identifier : service category
peer network formation information
phase descriptor
slot allocation descriptor
discovering interval
peer network synchronization interval
PD wake-up interval
peer discovery procedure
send peer discovery frame every Td
peer network service capable PDs respond (address, capability) and are synchronized
host notifies the network starting time to each PD

27. Peer Discovery (II) peer discovery request frame
provide phase duration
slot allocation schedule on each phases
Octet: 1 6 2
0/2/4/6 1
Peer Network Information Element Type
Peer Network Information Element Length
Timestamp
Phase Descriptor
Slot Allocation Descriptor 1
Residual Time
Bits: 4 4
Discover
Peer-to-Peer
Handshaking
Reserved
Bits: 4 4
Pause
Host
Guest
Relay
Group

28. master clock of the peer networks
Synchronization (I)
synchronize global clock of the peer networks
adjust the length of the base timeslot
compensate the oscillator drift of a peer network device
align timeslots of the peer networks in proximity
base timeslot
master clock of the peer networks
clock compensation
PD n of PACN x
PD m of PACN x
timeslot alignment
PD l of PACN y

29. Synchronization (II) clock source
A device, master clock capable, listens for 2*minSyncAdjustInterval
if peer network synchronization frame not found, starts to transmit a set of peer network synchronization frames
set of peer network synchronization frames
transmit a peer network synchronization frame every baseTimeslotLength*unitTimeslot (sync frame interval)
for syncBurstInterval (sync frame burst interval)
minimum sync adjust interval
sync frame burst interval
base timeslot
sync frame interval
master clock of the peer networks SF SF SF SF SF SF
Octet: 1
Octet: 2 6
Peer Network Information Element Type
Peer Network Information Element Length
Sequence Number
Sync Clock Time

30. Synchronization (III)
peer network synchronization frame
peer network information element : peer network synchronization
Sync Clock Time : sequential number of base timeslot in which peer network synchronization frame is sent
peer network descriptor
provide sync clock time
clock synchronization can be performed during the peer discovery phase
Octet: 1
Octet: 2 6
Peer Network Information Element Type
Peer Network Information Element Length
Sequence Number
Sync Clock Time
Octet: 1 6 2 1
Peer Network Information Element Type
Peer Network Information Element Length
Timestamp
Phase Descriptor
Slot Allocation Descriptor
Residual Time

31. allocated for peer discovery phase
Scheduling (I)
configure the resource allocation schedule of a peer network
phases of the resource allocation
clock synchronization
peer discovery
peer association
peer-to-peer data communication
peer disassociation
resource allocation
set the length of unit timeslot for a peer network
combinations of pause, host, guest, group, relay for each phase
peer network service profile
specify the resource allocation schedule
allocated for peer discovery phase
allocated for host
allocated for pause
allocated for guest
base timeslot
unit timeslot
peer network

32. peer-to-peer communication phase
Scheduling (II)
peer network service profile
specification of combined phases
specification of resource allocation for a phase
service example : real-time short message exchange in a peer network with moving PDs
peer discovery – peer-to-peer communication
peer discovery phase : host – pause – guest – pause
peer-to-peer comm phase : host – guest – pause – guest – host – pause
unit timeslot : 2 base timeslots
host timeslots : 3 unit timeslots
pause timeslots : 2 unit timeslots
guest timeslots : 1 unit timeslots
peer discovery phase
peer-to-peer communication phase
host timeslots
pause timeslots
guest timeslots
host timeslots
guest timeslots
peer network

33. Scheduling (III) peer network service profile peer network descriptor
profile registry
1,024 types peer network per class
specify combined phases for a peer network
length of the network operation is set by host with a peer network descriptor
peer network descriptor
phase descriptor
Peer Discovery Phase Length, Peer Association Phase Length, Peer-to-Peer Communication Phase Length, Peer Disassociation Phase Length,
resource allocation descriptor
Pause Timeslots Length, Host Timeslots Length, Guest Timeslots Length, Group Timeslots Length, Relay Timeslots Length

34. Interference Avoidance (I)
interference avoidance in multiple peer networks
access control as a guest
participates on single peer network
implicit control : select backoff time before access
participates on multiple peer networks
explicit control : defer to access, schedule peer communications among peer networks
access control as a host
select start time of the peer communication phase
schedule peer communications among peer networks
interference avoidance in single peer network
assign dedicated timeslots for supporting high priority service
backoff dependent upon the access priority

35. Interference Avoidance (II)
interference avoidance in multiple peer networks
access control as a guest
participates on single peer network
implicit control : select backoff time before access
participates on multiple peer networks
explicit control : defer to access, schedule peer communications among peer networks
access control as a host
select start time of the peer communication phase
schedule peer communications among peer networks
hosting phase
P2P phase
PD 1 of PACN1 PD PD PD PB PB PB
hosting phase
P2P phase
PD 1 of PACN2 PD PD PB PD PB PB
PD 2 of PACN1 PI
PD 2 of PACN2 PI

36. Start Interference Avoidance
host or guest
host
guest
interfere sync slot, host slot, relay slot of other peer network?
host
serve to single peer network? Y N
access link cause interference to other peer network?
interfere sync slot, host slot, relay slot of other peer network? Y
adjust slot allocation for host, guest, relay, pause Y Y
perform CCA
discard possible ? N
select start time of peer data phase
not occupied? Y
remove transmit request
delay transmission Y Y
use slot
complete
complete
complete
complete

37. Groupcast group in a peer network addressing form a group
collaboration by sharing information
provide missing part of service specific information
form a group with implicit invite and explicit grouping
addressing
unicast in a peer network
network ID + group ID + local device ID
broadcast in a peer network
network ID + broadcast group ID + broadcast device ID
groupcast in a peer network
network ID + group ID + broadcast device ID
broadcast in proximity
set broadcast frame type
form a group
any guest can invite a device in a peer network by advertising needed service capability with group ID
in implicit grouping, a PD responses to the group data request by sending group data response
in explicit grouping, a PD responses to the group request and can send group data frame after receiving ACK
PAC
device6
peer network 1
peer network 2
group 1
peer network 3

38. Broadcast broadcast in proximity broadcast in a peer network
use broadcast frame type
network identifier indicates the source network of the broadcast frame
broadcast in a peer network
use peer device broadcast address
host can transmit a broadcast frame in guest timeslots as well as in host timeslots
PAC
device6
peer network 1
peer network 2
group 1
peer network 3
PDH

39. QoS multiple class of data primitives
specify data rate, transmission QoS, unicasting/groupcasting/broadcasting
PDD-DATA
data rate
service class : real-time, reliable, best effort
address : unicasting, broadcasting
PDD-DATA-GROUP
network service profile ID
implicit grouping and data request
explicit grouping before data request

40. Multi-hop Operation to extend peer network coverage
peer network relay capable PD finds an isolated PD by receiving the device advertisement frame
peer network relay capable PD starts to retransmit clock sync frame and outward frames from host on relay timeslots assigned to the relay PD
isolated PD can send frames on relay timeslots with CCA
relay PD receives inward frame and retransmit the frame on selected slots base upon the frame type
this procedure is for one-hop relay
multi-hop operation can be provided by using the modified 15.4k TRLE (Timeslot Relaying based Link Extension)
host timeslots
pause timeslots
guest timeslots
relay timeslots
guest timeslots
PD in tier 0
host timeslots
pause timeslots
guest timeslots
relay timeslots
guest timeslots
PD in tier 1

41. Relative Positioning relation matrix based positioning
PD 1a
PD 1b
PD 0
tier 1
tier 2
tier 3
PD 1b2a
PD 1c
relation matrix based positioning
angular distance to a neighbor PD
for PDs in a fixed peer network
to search a nearest PD to support
establish PD map
two hop neighbor’s relation matrix
neighbor local device identifier
RSSI
distribute in a device advertisement frame
neighbor relation list field
relative positioning conjecture

42. Higher Layer Interaction
service access points
to the next higher layer
link layer service access point
PD management service access point
to the external network
external PD management service access point
service primitives
peer network management primitives
EXTM-PUT-SERVICE
PDM-SET-SERVICE
PDM-GET-SERVICE
PDM-START-DEVICE
peer link management primitives
PDL-JOIN-PEER
PDL-LEAVE-PEER
PDL-MANAGE-PEER
peer device data primitives
PDD-DATA
PDD-DATA-GROUP
Link
Application
PHY
Network
PD Management Entity
IEEE Link Network sublayer
PAC Service Adaptation sublayer
IEEE Medium Access Control sublayer
IEEE Link Control sublayer
IEEE PHY
PHY-SAP
LINK-SAP
EXTMANG-SAP
PDMANG-SAP
External Device Management
Entity