Transcript HIgh PErformance Radio Local Network (HIPERLAN) – Type 1

HIgh PErformance Radio Local Area
Network
(HIPERLAN) – Type 1
Sean S. Wang
Department of Computer Science and Information Engineering
Tamkang University
Wireless Mobile Network Lab. C.S. TKU
1
Agenda




Overview
Medium Access Control Sub-layer (MAC)
Channel Access Control Sub-layer (CAC)
Physical Sub-layer (PHY)
Wireless Mobile Network Lab. C.S. TKU
2
Agenda

Overview






ETSI ETR 069 - Radio Equipment and Systems (RES);
HIgh PErformance Radio Local Area Network (HIPERLAN);Services
and facilities
ETSI ETR 133 - Radio Equipment and Systems (RES);
HIgh PErformance Radio Local Area Networks (HIPERLAN);System
definition
ETSI EN 300 652 - Broadband Radio Access Networks (BRAN);
HIgh PErformance Radio Local Area Network (HIPERLAN) Type
1;Functional specification
Medium Access Control Sub-layer (MAC)
Channel Access Control Sub-layer (CAC)
Physical Sub-layer (PHY)
Wireless Mobile Network Lab. C.S. TKU
3
What’s HIPERLAN


Developed within the European Telecommunication
Standards Institute (ETSI) during the period 1991 to October
1996
A radio communication sub-system



Intended for integration with computer systems
Provides high speed, short distance radio links
Be used for local, in-house networking
Wireless Mobile Network Lab. C.S. TKU
4
HIPERLAN Properties





Provide a service that is compatible with the service in ISO
15802-1 specification
Deploy in a pre-arranged or ad-hoc fashion
Support node mobility
Support asynchronous and time-bounded communication by
means of a Channel Access Mechanism (CAM) with priorities
Easy establishment of wireless ad-hoc LAN, by using
distributed topology and routing functions in the MAC layer
Wireless Mobile Network Lab. C.S. TKU
5
HIPERLAN Applications





Office automation
Financial service
Medical and hospital systems
Education and training
Industrial automation
Wireless Mobile Network Lab. C.S. TKU
6
HIPERLAN General Requirements (1)

Distributed processing systems




The extensions and alternatives of wired LANs based on Ethernet
and Token Ring standards
Short message exchange (the order of a few hundred bytes)
High frequency (the order of hundreds per second)
Asynchronous and time-bounded services


Asynchronous: data
Time-bounded: voice/video
Wireless Mobile Network Lab. C.S. TKU
7
HIPERLAN General Requirements (2)

Mobility


Security



Maximum linear speed: 10 m/s (36 km/h)
Protects the users from eavesdropping (竊聽) and data injection
Power, size and costs
Interoperability

All nodes in HIPERLAN can inter-operate to the basic common air
interface
Wireless Mobile Network Lab. C.S. TKU
8
HIPERLAN Operating Requirements (1)


Over air data rate: 23.5 Mbps
Net data rate (overhead is not included)


Asynchronous: up to 20 Mbps
Time-bounded





Video phone: at least 64 kbps
ISDN: 2048 kbps
100 MHz of spectrum at 5.15-5.25 GHz (optional 5.25-5.30
GHz)
Three channels in 100 MHz, five channels in 150 MHz
Transmit power classes

10 mW, 100 mW, and 1000 mW
Wireless Mobile Network Lab. C.S. TKU
9
HIPERLAN Operating Requirements (2)

Latency




Delay


Application-dependent, not defined
Delay variance



How quick the system is able to response to requests for service
Asynchronous: less than 1 ms (at 30% capacity)
Time-bounded: not defined
Asynchronous: no limit
Time-bounded: < (3.0 ms)2
Systems throughput and system capacity

Application-dependent
Wireless Mobile Network Lab. C.S. TKU
10
HIPERLAN Operating Requirements (3)

Range



To 50 m at 20 Mbps
To 800 m at 1 Mbps
Error rate



MPDU detected: better than 10-3
MPDU undetected: better than 8  10-8
MSDU undetected: better than 5  10-14
Wireless Mobile Network Lab. C.S. TKU
11
HIPERLAN Interworking

MAC level bridging model
Wireless Mobile Network Lab. C.S. TKU

Network level interworking
12
HIPERLAN Services

Asynchronous services


Asynchronous packet transfer/broadcast service
Time-bounded services




Require the establishment of a connection between sender and
receiver
Rely on connection-oriented communication protocol
Provide services at data rates of multiples of 64 kbps up to at least
2048 kbps
These services in a HIPERLAN node are optional
Wireless Mobile Network Lab. C.S. TKU
13
HIPERLAN Architectures (1)
 Ad hoc
 every device can communicate directly to each other device
 Infrastructure
 Node has forwarder and nonforwarder roles
 Each nonforwarder node should select at least one of its
neighbors as a forwarder
 Forwarder and nonforwarder nodes need to periodically update
the databases
Wireless Mobile Network Lab. C.S. TKU
14
HIPERLAN Reference Model
IEEE
802.11
Application layer
Presentation layer
higher layer protocols
Session layer
Transport layer
LLC
Network layer
Medium Access Control
(MAC) Sublayer
Data Link layer
Channel Access Control
(CAC) Sublayer
MAC
Physical layer
Physical (PHY) layer
PHY
OSI Reference Model
Wireless Mobile Network Lab. C.S. TKU
HIPERLAN Reference Model
15
HIPERLAN Communication Model
higher layer protocols
MSDU
MSAP
HIPERLAN MAC Service
MSDU
MSAP
HMPDU
HIPERLAN MAC Protocol
HMPDU
HCSDU
HCSAP
HIPERLAN CAC Protocol
HCSDU
HCSAP
HCPDU
HIPERLAN CAC Protocol
HCPDU
data burst
HIPERLAN Physical Protocol
data burst
MSAP: MAC Service Access Point
MSDU: MAC Service Data Unit
HMPDU: HIPERLAN MAC Protocol Data Unit
Wireless Mobile Network Lab. C.S. TKU
MTU = 2383 octets
MTU = 2422 octets
HCSAP: HIPERLAN CAC Service Access Point
HCSDU: HIPERLAN CAC Service Data Unit
HCPDU: HIPERLAN CAC Protocol Data Unit
16
Agenda


Overview
Medium Access Control Sub-layer (MAC)



ETSI EN 300 652 - Broadband Radio Access Networks (BRAN);
HIgh PErformance Radio Local Area Network (HIPERLAN) Type 1;Functional
specification
Channel Access Control Sub-layer (CAC)
Physical Sub-layer (PHY)
Wireless Mobile Network Lab. C.S. TKU
17
MAC Sub-layer

MAC layer involved in the following procedures




Network establishment, addition of a node in a network and
removal of a node from a network (Look Up function)
Topology updates and packet routing determination as well
as packet forwarding, controlled by the Routing Information
Maintenance function and the User Data Transfer function
Power Conservation by declaring periods in which the receiver
of a node is active and can listen to transmitted to packets
Calculation of the channel access priority of packets to be
transmitted
Wireless Mobile Network Lab. C.S. TKU
18
MAC Services



The HIPERLAN MAC service definition is based on the ISO
MAC service specification in ISO 15802-1
The maximum MSDU size is 2383 octets
The MAC services
 HIPERLAN look-up
 Power conservation
 User data transfer
 Routing information maintenance
 HMPDU transfer
Wireless Mobile Network Lab. C.S. TKU
19
HIPERLAN Reference Model
HIPERLAN
Look-up
Function
User Data
Transfer
Function
Routing
Power
Information
Conservation
Maintenance
Function
Function
MAC PDU Transfer Function
Channel Access Control Layer
Physical Layer
Wireless Mobile Network Lab. C.S. TKU
20
MAC Functions




System Co-ordination Function (SCF)
Data Transfer Service (DTS) Function
HIPERLAN Addressing Function
HIPERLAN Forwarding Function
Wireless Mobile Network Lab. C.S. TKU
21
System Co-ordination Function (SCF)

Include Multi-Channel Resource Sharing (MCRS) and Power
Conservation Management (PCM) functions







Create a HIPERLAN
Enable an individual node to join or leave a given HIPERLAN
Control encryption of MSDU data
Enable and disable HIPERLAN forwarding
Enable co-operating HIPERLAN devices using power conservation
techniques to communication in a satisfactory manner
Enable HIPERLAN operation in a multi-channel environment
Collect statistics
Wireless Mobile Network Lab. C.S. TKU
22
Data Transfer Service (DTS) Function

Include equitable access and power conservation transmission
functions



Aim to achieve equitable channel usage among competing
HIPERLAN nodes and MPDUs given multiple levels of transmission
priority
Define means for the delayed transmission of MPDUs destined for
devices known to be applying power conservation techniques
Deliver to the MAC service user the MSDUs received
Wireless Mobile Network Lab. C.S. TKU
23
Addressing and Forwarding Function

HIPERLAN Addressing Function



Support for broadcast, multicast and unicast transmission amongst
HIPERLAN nodes within the same HIPERLAN
MAC service addressing and HIPERLAN addressing are
independent
HIPERLAN Forwarding Function


Establish and maintain connectivity in s single HIPERLAN
Forwarding routes MPDUs between source and destination via one
or more forwarder nodes
Wireless Mobile Network Lab. C.S. TKU
24
HIPERLAN Identification Scheme



Each HIPERLAN shall be assigned a numerical HIPERLAN
identifier and a character-based HIPERLAN name
A special HIPERLAN identifier, Any_HIPERLAN, is used for any
group
The method of HIPERLAN identifier and name assignment are
outside the scope of the ETSI
Wireless Mobile Network Lab. C.S. TKU
25
HIPERLAN Name/Identifier

HIPERLAN name


Fixed-length 32 16-bit characters (64 octets)
HIPERLAN identifier (4 octets)
HIPERLAN
identifier
Valid range of
value or reserved
value
Any_HIPERLAN
0
It identifies any (non-specific) HIPERLAN
-
1 ~ (231-1)
It identifies a specific HIPERLAN without
applying encryption-decryption scheme
-
231 ~ (232-1)
It identifies a specific HIPERLAN with
applying encryption-decryption scheme
Wireless Mobile Network Lab. C.S. TKU
Description
26
MAC Service Access Point Address
(MSAP-address)


48-bit LAN MAC address is adopted
Individual-MSAP-address



Identify a single MSAP, its attached HMS-user and HM-entity
For unicast
Group-MSAP-address


Identify a group MSAPs and their attached HMS-users
For multicast
Wireless Mobile Network Lab. C.S. TKU
27
HIPERLAN MAC Protocol Data Unit
HMPDU
Description
Define HMPDU type
value
DT-HMPDU
DaTa HMPDU
1
LR-HMPDU
Look-up Request HMPDU
2
LC-HMPDU
Look-up Confirm HMPDU
3
IP-HMPDU
Individual-attention Pattern HMPDU
4
GP-HMPDU
Group-attendance Pattern HMPDU
5
TC-HMPDU
Topology Control HMPDU
6
HO-HMPDU
HellO HMPDU
7
Wireless Mobile Network Lab. C.S. TKU
28
MAC Information Base (1)

p-saver information base



p-supporter information base



p-supporter supports unicast HCSDU transfer to its neighbouring
p-savers
p-supporter records the individual-attention pattern
p-saver supports multicast HCSDU transfer by its neighbouring
p-supporters
p-saver records the group-attendance pattern
Duplicate detection information base


To avoid redundant processing
Every HM-entity records {Dsrc, Dseq} to delete
Wireless Mobile Network Lab. C.S. TKU
29
MAC Information Base (2)

Route information base


Every HM-entity records {RDest, RNext, RDist} where RDist is the hop
count
Relay role

A HM-entity is either a non-forwarder or a forwarder
Relay type
Valid reserved
value
Description
R_NonForwarder
1
the relevant HM-entity is a non-forwarder
R_Forwarder
2
the relevant HM-entity is a forwarder
Wireless Mobile Network Lab. C.S. TKU
30
MAC Information Base (3)

Neighbour information base

Every HM-entity records {NNbour, NStatus}


NNbour : HCSAP-address (=HMSAP-address)
NStatus : neighbour status
Neighbour
status
Valid
reserved
value
Description
N_Asym
1
Local HM-entity has an asymmetric link with neighbour
N-Sym
2
Local HM-entity has a symmetric link with neighbour
N_MultiRelay
3
Local HM-entity has a symmetric link with neighbour
and has selected this neighbour as its multi-point relay
Wireless Mobile Network Lab. C.S. TKU
31
MAC Information Base (4)

Hello information base

Every HM-entity records {HDest, HStatus, HNext} where HDest has a
status HStatus and can be reached by HNext
HStatus
Description
H_NeighbourNF
HDest identifies a neighbouring non-forwarder
H_NeighbourF
HDest identifies a neighbouring forwarder
H_TwoHop
HDest is two hops away from the local HM-entity and
HNext identifies a mutual neighbouring forwarder
Wireless Mobile Network Lab. C.S. TKU
32
MAC Information Base (5)

Source Multipoint relay information base


Topology information base


A forwarder records {SSMR, SSeq} where SSMR has selected it as a
multipoint relay with the sequence number SSeq
A forwarder records {TDest, TLast, TSeq} where TDest has selected TLast
as a multipoint relay with the sequence number Tseq
Alias information base

Every HM-entity records {AOri, AAlias} where address AOri is outside
HIPERLAN and associated with AAlias address
Wireless Mobile Network Lab. C.S. TKU
33
Look-up Function

Look-up process
HIPERLAN-A
LR-HMPDU
LC-HMPDU
HIPERLAN-B

An HM-entity which has not been assigned to any specific
HIPERLAN may invoke HIPERLAN look-up requests and
collect HIPERLAN information
Wireless Mobile Network Lab. C.S. TKU
34
Look-up Function Procedures

HIPERLAN information query


HIPERLAN information declaration


The attached HMS-user issues an HM-LOOKUP request primitive
to determine the HIPERLAN names and the associated
identifiers
To declare the HIPERLAN name and identifier of the local HMentity’s HIPERLAN upon receipt of an LR-HMPDU
HIPERLAN information collection

To process a received LC-HMPDU
Wireless Mobile Network Lab. C.S. TKU
35
Look-up Function Procedures (*)
HM-entity
Neighbouring entity
HIPERLAN information query
LR-HMPDU
HIPERLAN information query
LC-HMPDU
HIPERLAN information collection
Wireless Mobile Network Lab. C.S. TKU
36
Power Conservation Function (1)



Allow a node enter the power conservation state, and it should
periodically wake up a period of time to receive the packets
HIPERLAN power conservation function is based on mutual
respect between p-saver and p-supporter
Two roles of power conservation

p-saver


Refer to a HM-entity when it will be able to receive HMPDUs
p-supporter

Refer to a HM-entity when it will transfer HMPDUs to its neighbouring
p-savers
Wireless Mobile Network Lab. C.S. TKU
37
Power Conservation Function (2)
p-supporter
declared deferred multicast pattern
p-saver
declared wake pattern
actual wake pattern
Perform OR function
Wireless Mobile Network Lab. C.S. TKU
38
The Recurring Patterns (1)


A p-saver/p-supporter is assigned one and only one recurring
individual-attention/group-attendance pattern, of which it
makes regular declaration in IP-HMPDU/GP-HMPDU
Three timing elements
practice
interval
pattern offset
pattern period
•
•
•
practice interval: the duration of individual-attention/group-attendance interval
pattern offset: the amount of time which has elapsed since the most recent start of practice interval
pattern period: the amount of time between the start of successive practice intervals
Wireless Mobile Network Lab. C.S. TKU
39
The Recurring Patterns (2)

Valid values for the timing elements of a recurring pattern
Timing elements


Valid range of value (ms)
pattern offset
0 - 10000
pattern period
500 - 10000
practice interval
500 - 10000
The practice interval is no greater than the pattern period
The practice offset is no greater than the pattern period
Wireless Mobile Network Lab. C.S. TKU
40
Power Conservation Function Procedures (1)

Individual-attention pattern declaration

p-saver


periodically declare a IP-HMPDU (Individual-attention Pattern) to tell
its neighbouring p-supporters the wake up period and the interval it
awake (practice interval, pattern offset and pattern period)
Group-attendance pattern declaration

p-supporter


transfer to p-savers while they are awake
periodically declare a GP-HMPDU (Group-attendance Pattern) to tell
its neighbouring p-savers the group-attendance period which used to
transfer the multicast packets
Wireless Mobile Network Lab. C.S. TKU
41
Power Conservation Function Procedures (2)

Individual-attention pattern recording


Group-attendance pattern recording


p-saver records a neighbouring p-supporter’s declared groupattendance pattern upon receipt of an GP-HMPDU
Expired individual-attention pattern entry removal


p-supporter records a neighbouring p-saver’s declared
individual-attention pattern upon receipt of an IP-HMPDU
p-supporter removes an individual-attention pattern from the local
p-saver information base upon expiry of its holding time
Expired group-attention pattern entry removal

p-saver removes a group-attention pattern from the local psupporter information base upon expiry of its holding time
Wireless Mobile Network Lab. C.S. TKU
42
Power Conservation Function Procedures (*)
p-saver
p-supporter
Individual-attention pattern declaration
IP-HMPDU
Individual-attention pattern recording
holding time timeout
Expires individual-attention pattern entry removal
Wireless Mobile Network Lab. C.S. TKU
43
Power Conservation Function Procedures (*)
p-supporter
p-saver
Group-attendance pattern declaration
GP-HMPDU
Group-attendance pattern recording
holding time timeout
Expires group-attendance pattern entry removal
Wireless Mobile Network Lab. C.S. TKU
44
User Data Transfer Function





Support MSDU transfer between HMS-users in accordance
with the HIPERLAN MAC service definition
MSDU is submitted by a HMS-user and transmitted by the
attached HM-entity in the DT-HMPDU
DT-HMPDU is relayed towards the destination(s) if MSDU
lifetime has not expired
When a DT-HMPDU arrives at the destination HM-entity, it is
delivered to the HMS-user
If applying HIPERLAN encryption-decryption scheme


MSDU may be encrypted at the HM-entity attached to the source
MSAP
MSDU may be decrypted at the HM-entit(y/ies) attached to the
destination MSAP(s)
Wireless Mobile Network Lab. C.S. TKU
45
User Data Transfer Function Procedures (1)

Sanity check computation


User data encryption-decryption


To compute the sanity check on the octet sequence in the DTHMPDU from the KID (Key Identifier) to the SC (Sanity Check)
To obtain the encrypted or decrypted contents of the UD (User
Data) of the DT-HMPDU
HMQoS failure reporting

To inform the attached HMS-user that its previously issued HMUNITDATA request primitive cannot be honoured because the
associated HMQoS measures cannot be met
Wireless Mobile Network Lab. C.S. TKU
46
User Data Transfer Function Procedures (2)

User data acceptance


User data delivery


To process the attached HMS-user’s MSDU transfer request, when
the attached HMS-user issues a HM-UNITDATA request primitive
To delivery the received MSDU to the attached HMS-user upon
receipt of a DT-HMPDU conveying a MSDU whose destination
MSAP-address identifies the attached HMS-user
User data forwarding

Forwarder forwards the received DT-HMPDU towards its
destination upon receipt of a DT-HMPDU
Wireless Mobile Network Lab. C.S. TKU
47
User Data Transfer Function Procedures (*)
HM-user (S)
HM-entity (S)
HM-entity
HM-user (D)
HM-UNITDATA request primitive
MSDU
Sanity check computation
User data encryption
QoS Failure
HMQoS failure reporting
HMQOSFAILURE
indication primitive
DT-HMPDU
User data acceptance
User data decryption
Unicast
User data delivery
HM-UNITDATA indication primitive
MSDU
User data forwarding
Wireless Mobile Network Lab. C.S. TKU
Multicast
48
Routing Information Maintenance Function


This function is concerned with the local HM-entity’s exchange
of routing information with the other HM-entities and its
maintenance of local routing information
Neighborhood discovery


Every HM-entity declare periodically Hello HIPERLAN MAC
Protocol Data Unit (HO-HMPDU) to exchange the neighbour
information
The HO-HMPDU contains the addresses and statuses of the
sender and all its neighbours to build a routing information base
Wireless Mobile Network Lab. C.S. TKU
49
Routing Information Maintenance Function
Procedures (1)

Route determine


Route information base establishment


To (re-)establish the local route information base upon
modification of the local topology information base and/or the
neighbour information base
Multipoint relay selection


To determine the route for a DT-HMPDU awaiting transmission
To select a set of neighbouring forwarders as the multipoint
relays for optimizing the distribution of HMPDUs
Neighbour information declaration

To declare periodically the neighbour information to the
neighbouring HM-entities
Wireless Mobile Network Lab. C.S. TKU
50
Routing Information Maintenance Function
Procedures (2)

Neighbour information recording


Source multipoint relay information declaration


To record the neighbour information of a neighbouring HM-entity in
the local HM-entity’s neighbour information base, hello
information base and source multipoint relay information base
upon receipt of a HO-HMPDU
A forwarder declares periodically its source multipoint relay
information to the forwarders in the HIPERLAN
Source multipoint relay information recording

To record the source multipoint relay information of a forwarder
in the local HM-entity’s topology information base upon receipt of
a TC-HMPDU
Wireless Mobile Network Lab. C.S. TKU
51
Routing Information Maintenance Function
Procedures (3)

TC-HMPDU forwarding


Alias address learning


A forwarder forwards the received TC-HMPDU to other forwarders
upon receipt of a TC-HMPDU from one of the local HM-entity’s
source multipoint relays
To learn an alias address for a MSAP outside of the HIPERLAN
upon receipt of a DT-HMPDU
Expired neighbour entry removal

To remove a neighbour entry from the local neighbour information
base upon expiry of its holding time
Wireless Mobile Network Lab. C.S. TKU
52
Routing Information Maintenance Function
Procedures (4)

Expired source multipoint relay entry removal


Expired topology entry removal


To remove a source multipoint relay entry from the local source
multipoint relay information base upon expiry of its holding
time
To remove a topology entry from the local topology information
base upon expiry of its holding time
Expired alias entry removal

To remove an alias entry from the local alias information base
Wireless Mobile Network Lab. C.S. TKU
53
Routing Information Maintenance Function
Procedures (*)
HM-user (S)
HM-entity (S)
HM-entity
HM-user (D)
HM-UNITDATA request primitive
MSDU
Sanity check computation
User data encryption
QoS Failure
HMQoS failure reporting
HMQOSFAILURE
indication primitive
DT-HMPDU
User data acceptance
User data decryption
Unicast
User data delivery
HM-UNITDATA indication primitive
MSDU
User data forwarding
Wireless Mobile Network Lab. C.S. TKU
Multicast
54
Encryption-decryption Scheme (1)


Key length in the HIPERLAN key-set is 30 bits
Key identifier ( in DT_HMPDU)



To encrypt and decrypt the user data
The assignment of the specific key to a key identifier value is
outside this document (EN 300 652)
Valid key identifier values
Key identifier
Valid range of value
or reserve value
No_Key
0
-
1-3
Wireless Mobile Network Lab. C.S. TKU
Description
the user data is not encrypted
the user data is encrypted
55
Encryption-decryption Scheme (2)

The single encryption-decryption algorithm


Requires an identical key (30-bit with key identifier) and an
identical initialization vector
Referred from HIPERLAN key-set
key
identifier
HIPERLAN
key-set
key
initialization
vector
Random sequence
generator
data
Transmitter
Wireless Mobile Network Lab. C.S. TKU
XOR
Key
identifier
HIPERLAN
key-set
Initialization
vector
Encrypted
data
Encrypted
Transmission
key
XOR
Random sequence
generator
data
Receiver
56
HMPDU Transfer Function



This function is concerned with the transmission and reception
of a HMPDU using the CAC service
When the CAC service is ready to accept a HMPDU
transmission attempt, the HM-entity selects for transmission the
most important HMPDU awaiting transmission
DT-HMPDUs and TC-HMPDUs which have previously
transmitted or received are remembered to avoid redundant
processing
Wireless Mobile Network Lab. C.S. TKU
57
HMPDU Transfer Function Procedures (1)

Expired HMPDU removal


HMPDU selection



To remove a HMPDU awaiting transmission upon expiry of its
holding time
Select the most important HMPDU awaiting transmission for
transmission
Refer to the part of “The Channel Access Priority”
HMPDU transmission and retransmission

To transmit or retransmit the most important HMPDU awaiting
transmission for the following situations


When the attached HCS-provider issues a HC-SYNC indication
primitive
After the attached HCS-provider issues a HC-FREE indication
primitive and before it issues a subsequent HC-STATUS indication
primitive
Wireless Mobile Network Lab. C.S. TKU
58
HMPDU Transfer Function Procedures (2)

HMPDU reception


To receive a HMPDU from the attached HCS-provider when it
issues a HC-UNITDATA indication primitive
Expired duplicate detection entry removal

To remove a duplicate detection relay entry from the local
duplicate detection information base upon expiry of its holding
time
Wireless Mobile Network Lab. C.S. TKU
59
Channel Access Priority (1)




Generally, packets submitted to the MAC (HMQoS) are
assigned with one of two user priority level (0 for high and 1
for low), according to its HMPDU type
Every HMPDU has its lifetime (0-16000ms, default 500ms)
that it can remain available in its transmission journey
The remaining lifetime and remaining number of hops of a
packet are taken into consideration
The Normalized Residual lifetime (NRL) is computed by
dividing packet’s remaining lifetime with the remaining number of
hops
remaining lifetime
NRL 
remaining number of hops
Wireless Mobile Network Lab. C.S. TKU
60
Channel Access Priority (2)

HMQoS and channel access priority mapping
Normalized residual HMPDU lifetime
(NRL)
Channel access priority,
if Cpri is 0
Channel access priority,
if Cpri is 1
NRL  10 ms
0
1
10 ms  NRL  20 ms
1
2
20 ms  NRL  40 ms
2
3
40 ms  NRL  80 ms
3
4
80 ms  NRL
4 (default)
4
NOTE:

HMPDU selection is performed in the following order




The numerically lower value indicates higher channel access priority
With the high channel access priority
With the shortest normalized residual HMPDU lifetime
Any one
Refer to the part of “CAC Layer”
Wireless Mobile Network Lab. C.S. TKU
61
General Structure of HMPDU
Field name
Octet
HMPDU length indicator field (LI) = n
1–2
HMPDU type indicator field (TI)
3
…
4–n
Wireless Mobile Network Lab. C.S. TKU
LI: the number of octets in the whole HMPDU
TI: the HMPDU type
62
The Structure of DT-HMPDU
Field name
Octet
HMPDU length indicator field (LI) = n
1–2
HMPDU type indicator field (LI) = 1
3
Residual HMPDU lifetime field (RL)
4 –5
HMPDU sequence number field (PSN)
6–7
RL: the residual HMPDU lifetime
PSN: the HMPDU sequence number
Destination MSAP-address field (DA)
8 – 13
DA: the destination MSAP-address
Source MSAP-address field (SA)
14 – 19
SA: the source MSAP-address
Alias destination MSAP-address field (ADA)
20 – 25
Alias source MSAP-address field (ASA)
26 – 31
ADA: the alias destination MSAP-address
ASA: the alias source MSAP-address
User priority
field (UP) [bit 8]
MSDU lifetime field
(ML)
Key identifier field
(KID) [bit 8-7]
Initialization vector field
32
UP: the user priority
33
ML: the MSDU lifetime
34
KID: the identifier
(IV)
35 – 37
User data field (UD) [1 – 2383 octets]
38 – (n-2)
Sanity check field (SC)
(n-1) - n
Wireless Mobile Network Lab. C.S. TKU
IV: the initialization vector
UD: the unencrypted/encrypted MSDU
SC: the sanity check for the unencrypted MSDU
63
The Structure of LR-HMPDU/LC-HMPDU


LR-HMPDU
Field name
Octet
HMPDU length indicator field (LI) = 3
1–2
HMPDU type indicator field (TI) = 2
3
LC-HMPDU
Field name
Octet
HMPDU length indicator field (LI) = 71
1–2
HMPDU type indicator field (TI) = 3
3
HIPERLAN identifier field (HID)
4–7
HID: the HIPERLAN identifier
HIPERLAN name field (HN)
8 - 71
HN: the HIPERLAN name
Wireless Mobile Network Lab. C.S. TKU
64
The Structure of IP-HMPDU/GP-HMPDU


IP-HMPDU
Field name
Octet
HMPDU length indicator field (LI) = 9
1–2
HMPDU type indicator field (TI) = 4
3
Pattern offset field (PO)
4–5
PO: the pattern offset
Pattern period field (PP)
6–7
PP: the pattern period
Pattern interval field (PI)
8–9
PI: the pattern interval
GP-HMPDU
Field name
Octet
HMPDU length indicator field (LI) = 9
1–2
HMPDU type indicator field (TI) = 5
3
Pattern offset field (PO)
4–5
PO: the pattern offset
Pattern period field (PP)
6–7
PP: the pattern period
Pattern interval field (PI)
8–9
PI: the pattern interval
Wireless Mobile Network Lab. C.S. TKU
65
The Structure of TC-HMPDU
Field name
Octet
HMPDU length indicator field (LI) = n
1–2
HMPDU type indicator field (LI) = 6
3
Residual HMPDU lifetime field (RL)
4 –5
HMPDU sequence number field (PSN)
6–7
Originator HCSAP-address field (OA)
8 – 13
Multipoint relay set sequence number field (MSN) (see note)
14 – 15
Source multipoint relay HCSAP-address field (SMA) (see note)
16 – 21
{ MSN, SMA } pairs
22 – (n-8)
Multipoint relay set sequence number field (MSN) (see note)
(n-7) – (n-6)
Source multipoint relay HCSAP-address field (SMA) (see note)
(n-5) – n
OA: the HCSAP-address of the
HM-entity which originates
the TC_HMPDU
MSN: the multipoint relay set
sequence number
SMA: the HCSAP-address of a
source multipoint relay
Note: The MSN and the SMA exists in pairs in a TC-HMPDU. There may be 0 up to any number of
{ MSN, SMA } pairs in a TC_HMPDU, subject to the maximum size of the TC-HMPDU.
Wireless Mobile Network Lab. C.S. TKU
66
The Structure of HO-HMPDU
Field name
Octet
HMPDU length indicator field (LI) = n
1–2
HMPDU type indicator field (LI) = 7
3
Relay type indicator field (RTI)
4
Multipoint relay set sequence number field (MSN)
5–6
neighbour HCSAP-address field (NA) (see note)
7 – 12
neighbour status field (NS) (see note)
13
{ NA, NS } pairs
14 – (n-7)
neighbour HCSAP-address field (NA) (see note)
(n-6) – (n-1)
neighbour status field (NS) (see note)
n
RTI: the relay type
NA: the HCSAP-address of a
neighbouring HM-entity
NS: the neighbour status
Note: The NA and the NS exists in pairs in a HO-HMPDU. There may be 0 up to any number of
{ NA, NS } pairs in a HO_HMPDU, subject to the maximum size of the HO-HMPDU.
Wireless Mobile Network Lab. C.S. TKU
67
Predefined Values of HMPDU
Symbol
tIP
tGP
tTC
tHO
tA
lLR
lLC
lIP
lGP
lTC
lHO
pIP
pGP
pLR
pLC
pTC
pHO
tC
nUHD
nMHD
Use
holding time for the individual-attention pattern
holding time for the group-attendance pattern
holding time for the information from the received TC-HMPDU
holding time for the information from the received HO-HMPDU
holding time for an alias entry
HMPDU lifetime of the LR-HMPDU
HMPDU lifetime of the LC-HMPDU
HMPDU lifetime of the IP-HMPDU
HMPDU lifetime of the GP-HMPDU
HMPDU lifetime of the TC-HMPDU
HMPDU lifetime of the HO-HMPDU
HMPDU priority of the IP-HMPDU
HMPDU priority of the GP-HMPDU
HMPDU priority of the LR-HMPDU
HMPDU priority of the LC-HMPDU
HMPDU priority of the TC-HMPDU
HMPDU priority of the HO-HMPDU
HIPERLAN information collection interval
default hop distance for unicast MSDU transfer
default hop distance for multicast MSDU transfer
Predefined value
30000 ms
30000 ms
40000 ms
20000 ms
30000 ms
500 ms
500 ms
500 ms
500 ms
500 ms
500 ms
1
1
1
1
0
0
1000 ms
1
5
• Holding time: the time HM-entities keep HMPDUs in their base
• Lift time: the time HMPDU is available in its transmission journey
Wireless Mobile Network Lab. C.S. TKU
68
Agenda



Overview
Medium Access Control Sub-layer (MAC)
Channel Access Control Sub-layer (CAC)


ETSI EN 300 652 - Broadband Radio Access Networks (BRAN);
HIgh PErformance Radio Local Area Network (HIPERLAN) Type 1;Functional
specification
Physical Sub-layer (PHY)
Wireless Mobile Network Lab. C.S. TKU
69
CAC Sub-layer




CAC layer deals with the decision to transmit a packet or not
Channel Access Cycle
Maximum HCSDU size : 2422 octets
Specify four operations/functions




The operation of EY-NPMA
The channel permission function
The user data transfer function
The HCPDU transfer function
Wireless Mobile Network Lab. C.S. TKU
71
HCPDU

A HCPDU may have two parts



low-bit-rate part (LBR-part)
high-bit-rate part (HBR-part)
Two kinds of HCPDU


The LBR HCPDU: the acknowledgement HCPDU (AK_HCPDU)
The LBR-HBR HCPDU


Contain both the LBR-part and the HBR-part
The HBR-part may have 1-47 blocks of 52 octets
LBR-HBR HCPDU
Description
Defined HCPDU type value
CP-HCPDU
channel permission HCPDU
0
DT-HCPDU
data HCPDU
1
Wireless Mobile Network Lab. C.S. TKU
72
Non-Pre-emptive priority Multiple Access (NPMA)


Only data ready at the start of a channel access cycle may
content for channel access, and new data is not allowed to
access
NPMA defines three activity phases

Prioritization phase



Contention phase



Non-pre-emptive priority resolution is performed
Choose the nodes with the highest priority among all contending
nodes to enter the contention phase
Decide who could transmit data among those nodes with the same
priority
Include the elimination phase and the yield phase
Transmission phase
Wireless Mobile Network Lab. C.S. TKU
73
NPMA Channel Access Cycles


Channel free channel access cycle
Synchronized channel access cycle
elimination
phase
yield
phase
Contention Phase
priority resolution
contention resolution
data transmission
Prioritization Phase
Contention Phase
Transmission Phase
channel free condition
channel free
channel access cycle
synchronized channel access cycle
synchronized channel condition
Wireless Mobile Network Lab. C.S. TKU
74
The EY-NPMA Activities
priority detection
prioritization interval: 0 to 4 prioritization slot intervals
priority assertion
priority assertion interval
elimination bursting
elimination interval: 0 to 12 elimination slot intervals
elimination survival verification
elimination survival verification interval
yield listening
yield interval: 0 to 9 yield slot intervals
data transmission
transmission interval
unicast w/o ack
channel access burst
unicast data burst
unicast w/ ack
channel access burst
unicast data burst
multicast
channel access burst
elimination
phase
Prioritization Phase
missing ack
ack burst
multicast data burst
yield
phase
Contention Phase
idle channel for at least the channel free interval
Transmission Phase
channel free
channel access cycle
synchronized channel access cycle
idle channel in the channel synchronization interval,
after synchronization to the end of previous channel access cycle
Wireless Mobile Network Lab. C.S. TKU
75
The EY-NPMA Activities Example
D, F, K are survival,
then sense the
channel
A, D, F, H,
K
are survival
A(1)
B(4)
C(2)
listen
D(1)
E(4)
listen
F(1)
G(2)
H(1)
I(3)
listen
J(2)
K(1)
channel access burst
X
listen
channel access burst
e-burst
listen
sense
e-burst
listen
sense
data
X
listen
channel access burst
sense
X
X
listen
listen
X
X
listen
channel access burst
e-burst
X
X
listen
X
listen
listen
e-burst
channel access burst
e-burst
elimination
phase
Prioritization Phase
Wireless Mobile Network Lab. C.S. TKU
listen
sense
sense
X
yield
phase
Contention Phase
Transmission Phase
76
Prioritization Phase



There are total 5 channel access priority, which are numbered
from 0 to 4, with the 0 denoting the highest channel access
priority
The duration of prioritization phase is consisted of prioritization
slot intervals, and there could be 5 slots at most
A node whose data transmission attempt has a channel access
priority n, shall listen for n prioritization slot intervals



If the channel is sensed idle in the n prioritization slot intervals,
the node transmits immediately a channel access burst
Otherwise, the node stops its transmission attempt in the current
channel access cycle
At least one contending node will survive the prioritization
phase
Wireless Mobile Network Lab. C.S. TKU
77
Elimination Phase




Every node survived in the first phase transmits channel
access burst for several time slots (each one being 212 high
rate bit-period), and the number of slots is obtained by a
binomial distribution function, which may be 0 to 12
After the transmission of the elimination burst, node listens to
the channel for a period of time (called elimination survival
verification – 256 high-rate bit period), to verify if it is
eliminated by other contending nodes (i.e. if the channel is
sensed idle, then it is the survival)
The duration of the elimination interval is the longest elimination
burst among the contending nodes
At least one contending node will survive the elimination
phase
Wireless Mobile Network Lab. C.S. TKU
78
Yield Phase




Every survival node from last phase senses the channel for a
period which is a multiple ( 0 to 9) of 168 high rate bit-period,
decided by a probability function
If the channel is sensed idle for its yield interval, it could start to
transmit data
The duration of the yield interval is the shortest yield listening
among the contending nodes
At least one contending node will survive the yield phase
Wireless Mobile Network Lab. C.S. TKU
79
Transmission Phase


The transmission of data by the nodes survived in the channel
access cycle
Two kinds of data transmissions





A multicast transmission
A unicast transmission
For multicast, transmission is always successful
For unicast, if no collision happens, the phase would end
followed by a ACK packet (AK-HCPDU) indicating that the
packet was received correctly
A new channel access cycle is started after the transmission
of an ACK packet or the end of the expected transmission of
an ACK packet in unicast
Wireless Mobile Network Lab. C.S. TKU
80
Channel Permission Function




There are 5 defined communication channels
Channel 0, channel 1and channel 2 are the mandatory default
channels, in which transmission access is always permitted
Channel 3 and channel 4 are non-default channels, whose
availability is subject to national administration
Before having obtained permission to use a non-default channel,
an HC entities shall not transmit and shall ignore all received
HCPDU except the CP-HCPDU (channel permission) in that
non-default channel
Wireless Mobile Network Lab. C.S. TKU
82
Channel Permission Function Procedures

Channel permission declaration



Channel permission recording


To declare the applied channel permission information
CP-HCPDU transmitted by the LBR-HBR HCPDU transmission
procedure with the channel access priority 0 is generated
To record the channel permission information upon receipt of a CPHCPDU
Channel permission invalidation

To invalidate the permission to use the non-default channels upon
expiry of the permission validity time
Wireless Mobile Network Lab. C.S. TKU
83
User Data Transfer Function




Support HCSDU transfer between HCS-users in accordance
with the HIPERLAN CAC service definition
HCSDU is submitted by a HCS-user with a specified channel
access priority for transmission to a specified destination
HCSDU is transmitted by the attached HC-entity in the DTHCPDU
When a DT-HCPDU is received by the destination HC-entity, it is
delivered to the HCS-user
Wireless Mobile Network Lab. C.S. TKU
84
User Data Transfer Function Procedures (1)

Synchronized transfer invitation


Free transfer invitation


To invite the attached HCS-user to immediately initiate a HCSDU
transfer upon detection of the synchronized channel condition
To invite the attached HCS-user to initiate a HCSDU transfer at
any time upon detection of the channel free condition
Free transfer cancellation

To inform the attached HCS-user that the previous free transfer
invitation is cancelled and the local HC-entity is no longer
ready to accept any HCSDU transfer request upon nullification
of the channel free condition
Wireless Mobile Network Lab. C.S. TKU
85
User Data Transfer Function Procedures (2)

User data refusal


User data acceptance


To refuse a HCSDU transfer request from the attached HCS-user
To process the attached HCS-user’s transfer request
User data delivery

To deliver the received HCSDU to the attached HCS-user upon
receipt of a DT-HCPDU
Wireless Mobile Network Lab. C.S. TKU
86
HCPDU Transfer Function



Support the transmission and reception of a HCPDU
A multicast LBR-HBR transmission is always successful
A unicast LBR-HBR transmission is successful if and only if it is
acknowledged by a corresponding AK-HCPDU
Wireless Mobile Network Lab. C.S. TKU
87
HCPDU Transfer Function Procedures

LBR-part checksum computation


HBR-part checksum computation


To compute the hashed destination address for a given LBR-HBR
HCPDU
LBR-HBR HCPDU transmission


To compute separate 32-bit checksum for the entire HBR-part of a
LBR-HBR HCPDU except the CS
Hashed destination address computation


To compute separate 4-bit checksum for the HAD, the BLIR and
the AID of the LBR-part of a HCPDU
To transmit a generated LBR-HBR HCPDU
HCPDU reception

To process an HCPDU received from the physical layer
Wireless Mobile Network Lab. C.S. TKU
88
General Structure of LBR HCPDU
LBR-part
1
0
1
0
1
0
Bit
1
0
0
1
0-9
HBR-part Indicator field (HI) = 0
10
…
11 - n
Wireless Mobile Network Lab. C.S. TKU
HI: a value specifying if the HCPDU
has the LBR-part
89
General Structure of LBR-HBR HCPDU (1)
LBR-part
1
0
1
0
1
0
Bit
1
0
0
1
0-9
HI: a value specifying if the HCPDU has the LBR-part
HBR-part Indicator field (HI) = 1
10
Hashed Destination HCSAP-Address field (HDA)
11 – 19
HDACS: the checksum for the HDA
Hashed Destination HCSAP-Address CheckSum field
(HDACS)
20 – 23
BLIR: the number of blocks in the HBR-part
Block Length Indicator Replica field (BLIR)
24 – 29
BLIRCS: the checksum for the BLR
Block Length Indicator Replica checkSum field
(BLIRCS)
30 – 33
1
34
Wireless Mobile Network Lab. C.S. TKU
HDA: the hashed destination HCSAP-address
90
General Structure of LBR-HBR HCPDU(2)
HBR-part
Octet
1
TI: the LBR-HBR HCPDU type
BLI: the number of blocks in the HBR-part
Padding Length Indicator field (PLI) = m
2
PLI: the number of padding octets used in PAD
HIPERLAN Identifier field (HID)
3–6
HID: the HIPERLAN identifier
Destination HCSAP-Address field (DA)
7 – 12
DA: the destination HCSAP-address
Source HCSAP-Address field (SA)
13 – 18
SA: the source HCSAP-address
…
19 – (52n-m-4)
PADding field (PAD)
(52n-m-3) – (52n-4)
CheckSum field (CS)
(52n-3) – 52n
HCPDU Type Indicator
field (TI) [bit 8-7]
Block Length Indicator
field (BLI) [bit 6-1] = n
Wireless Mobile Network Lab. C.S. TKU
PAD: the padding octets of any values
if PLI is 0, the PAD does not exist
CS: the checksum for the entire HBR-part
except the CS
91
The Structure of AK-HCPDU
LBR-part
1
0
1
0
1
0
Bit
1
0
0
1
0-9
HBR-part Indicator field
(HI) = 0
10
Acknowledgement IDentifier field (AID)
11 – 18
AID: the acknowledgement identifier
Acknowledgement Identifier CheckSum field (AIDCS)
19 – 22
AIDCS: the checksum for the AID
Wireless Mobile Network Lab. C.S. TKU
92
The Structure of CP-HCPDU
HBR-part
HCPDU Type Indicator
field (TI) [bit 8-7] = 0
Octet
Block Length Indicator
field (BLI) [bit 6-1] = 1
1
Padding Length Indicator field (PLI) = 29
2
HIPERLAN Identifier field
(HID) = Any_HIPERLAN
3–6
Destination HCSAP-Address field
(DA) = All_Neighbours
7 – 12
Source HCSAP-Address field
(SA) = FF FF FF FF FF FF
13 – 18
Channel 3 field
(C3) [bit 8]
Channel 4 field
(C4) [bit 7]
Reserved
field
[bit 6-1] = 0
19
PADding field (PAD)
20 - 48
CheckSum field (CS)
49 - 52
Wireless Mobile Network Lab. C.S. TKU
Cx: a value specifying if channel x is permitted
to be used
Reserved field: unused, the value is 0
93
The Structure of DT-HCPDU
HBR-part
HCPDU Type Indicator
field (TI) [bit 8-7] = 1
Block Length Indicator
field (BLI) [bit 6-1] = n
Octet
1
Padding Length Indicator field (PLI) = m
2
HIPERLAN Identifier field (HID)
3–6
Destination HCSAP-Address field (DA)
7 – 12
Source HCSAP-Address field (SA)
13 – 18
User Data field (UD)
19 – (52n-m-4)
PADding field (PAD)
(52n-m-3) – (52n-4)
CheckSum field (CS)
(52n-3) – 52n
Wireless Mobile Network Lab. C.S. TKU
UD: the HCSDU in the same octet ordering of
the HCSDU
94
Agenda




Overview
Medium Access Control Sub-layer (MAC)
Channel Access Control Sub-layer (CAC)
Physical Sub-layer (PHY)

ETSI EN 300 652 - Broadband Radio Access Networks (BRAN);
HIgh PErformance Radio Local Area Network (HIPERLAN) Type 1;Functional
specification
Wireless Mobile Network Lab. C.S. TKU
95
PHY Sub-layer






Over air data rate: 23.5 Mbps
Maximum user data rate (per channel): over 18Mbps
30-50 meter range in typical indoor environments
100 MHz of spectrum at 5.15-5.25 GHz (optional 5.25-5.30 GHz)
Three channels in 100 MHz, five channels in 150 MHz
Three transmit power classes



10 mW
100 mW
1000 mW
Wireless Mobile Network Lab. C.S. TKU
96
Nominal Frequencies of RF Carrier

Carrier number
Centre Frequency, MHz
0
5 176,468 0
1
5 199,997 4
2
5 223,526 8
3
5 247,056 2
4
5 270,585 6
default
carriers
illegal in
some countries
All the node which belong to the same HIPERLAN/1 network
should use the same carrier
Wireless Mobile Network Lab. C.S. TKU
97
Approved 5 GHz Spectrum for USA and Europe
1 W*
1W
HIPERLAN band (Europe)
Radio output
power
Spectral
density
50 mW
250 mW
1W
2.5 mW/MHz
12.5 mW/MHz
50 mW/MHz
Antenna
gain
Frequency
(GHz)
+ 6 dBi
5.15
5.20
5.25
U-NII band
(USA)
+ 6 dBi
5.30
5.35
5.725
5.775
5.825
* Extensions on national bases
Wireless Mobile Network Lab. C.S. TKU
98
Channel Access Burst

Channel access burst


Used for priority assertion and elimination bursting defined in
EY-NPMA
Conveyed in HBR
Bits
11111010100010011100000110010110
Note: Bit transmission order is from left to right
Bit sequence used in an access burst
Wireless Mobile Network Lab. C.S. TKU
99
Data Bursts

Data bursts


The packets that contain upper layer information, or MAC control
information consist of two parts, a low bit rate part (LBR) and a
high bit rate part (HBR)
LBR data bursts



Data rate: 1.5 Mbps
FSK (Frequency Shift Keying) modulation
LBR-HBR data bursts


Data rate: 23 Mbps
GMSK (Gaussian Minimum Shift Keying) modulation
Wireless Mobile Network Lab. C.S. TKU
100
LBR Data Burst
low rate bit stream
time

The bit sequence in the AK-HCPDU is transmitted starting with
bit 0, using the low bit rate modulation scheme (FSK)
Wireless Mobile Network Lab. C.S. TKU
101
LBR-HBR Data Burst (1)
synchronization
and training
data block 0
sequence
450 bits
low rate
bit stream
496 bits
data block 1
data block (m-1)
496 bits
496 bits
high rate bit stream
time
NOTE: 1  m  47
Wireless Mobile Network Lab. C.S. TKU
102
LBR-HBR Data Burst (2)

A data burst contains the following fields




A number of low rate bits
A synchronization sequence of 450 high rate bits
A number (at least one) of blocks of 496 high rate bits of
interleaved, coded data
Each data block consists of 416 data high bit rate bits, divided
into 16 segments of 26 bits and each coded with a BCH (31,26)
code

The resulting 16*31=496 bits are block interleaved
Wireless Mobile Network Lab. C.S. TKU
103
HIPERLAN Family
HIPERLAN
Type 1
Wireless 8802
LAN
HIPERLAN
Type 2
Wireless IP,
ATM and
UMTS Short
Range Access
HIPERACCESS
Wireless IP
and ATM
Remote Access
(outdoor)
HIPERLINK
Wireless
Broadband
Interconnect
MAC
DLC
DLC
DLC
PHY
(5 GHz)
(23.5 Mbps)
PHY
(5 GHz)
(54 Mbps)
PHY
(various bands)
(25 Mbps)
PHY
(17 GHz)
(155 Mbps)
Wireless Mobile Network Lab. C.S. TKU
104