802.16: Introduction Reference: [1] S.J. Vaughan-Nichols, “Achieving Wireless Broad band with WiMax,” IEEE Computer Vol.37, No.6, PP.10- 13, June 2004. [2] IEEE Std 802.16-2004, “IEEE Standard for Local and metropolitan area networks--Part 16: Air Interface for Fixed Broadband Wireless Access Systems,” Oct. 200 4. [3] N. Liu, X. Li, C. Pei, and B. Yang, “Delay Char acter of a Novel Architecture for IEEE 802.16 Systems, ” Proceedings of Parallel and Distributed Computing, Applications and Technologies (PDCAT 2005), PP.293-296, Dec.2005. [4] IEEE Std 802.16e-2005, “IEEE Standard for Local and metropolitan area networks--Part 16: Air Interface for Fixed Broadband Wireless Access Systems--Amendment 2: Physical and Medium Access Control Layers for Combi ned Fixed and Mobile Operation in Licensed Bands,” Feb. 2006.
Computer Vol.37, No.6, PP.10-13, June 2004.[2] IEEE Std 802.16-2004, “IEEE Standard for Local and metropolitan area ne
tworks--Part 16: Air Interface for Fixed Broadband Wireless Access Systems,” Oct. 2004.
[3] N. Liu, X. Li, C. Pei, and B. Yang, “Delay Character of a Novel Architecture for IEEE 802.16 Systems,” Proceedings of Parallel and Distributed Computing, Applications and Technologies (PDCAT 2005), PP.293-296, Dec.2005.
[4] IEEE Std 802.16e-2005, “IEEE Standard for Local and metropolitan area networks--Part 16: Air Interface for Fixed Broadband Wireless Access Systems--Amendment 2: Physical and Medium Access Control Layers for Combined Fixed and Mobile Operation in Licensed Bands,” Feb. 2006.
[5] C. Cicconetti,L. Lenzini,E. Mingozzi, and C. Eklund, “Qality of service support in IEEE 802.16 networks,” IEEE Network, Vol.20, No.2, PP-55, March-April 2006.
Mobility Fixed Fixed and Portable Mobility, regional Roaming
Typical Cell Radius 1 to 3 miles 3 to 5 miles; Maximum range 30 miles
1 to 3 miles
7
IEEE Std 802.16 Protocol Layering
8
Service Specific Convergence Sublayer• Functions
– Provide transformation or mapping of external network data into MAC SDU for MAC CPS– Classify external network data and associate them to proper MAC service flow identifier (SFID) and connection id (CID)– Payload head suppression (optional)
– System access – Bandwidth allocation– Connection establishment and
maintenance with service flow• Support point-to multipoint
(PMP) and mesh modes• Support ARQ scheme• Dynamic uplink (UL) and
downlink (DL)• Flexible MAC with various
scheduling schemes for real time, non-real time and best effort services
10
Security Sublayer• Functions
– Authentication– Secure key exchange– Encryption
• Two component protocols– Encapsulation protocol for dataencryption– Privacy key management protocol (PKM)
11
Physical Sublayer• WirelessMAN-SC PHY
– Single-carrier modulation– Tangeted for 10-66 GHz frequency band
• WirelessMAN-SCa PHY– Single-carrier modulation– Frequency bands below 11GHz for NLOS
• WirelessMAN-OFDM PHY– OFDM modulation with a FFT size of 256– Frequency bands below 11GHz for NLOS– AAS and MIMO (also for OFDM-PHY)
• WirelessMAN-OFDMA PHY– OFDM modulation with scalable FFT sizes– Frequency bands below 11GHz for NLOS– Hybrid-ARQ– Fast-feedback mechanisms– Handover support
12
802.16 PHY Introduction
13
802.16 PHY Introduction(cont.)
• Support framing• Support both Time Division Duplex (TDD)
and Frequency Division Duplex (FDD) , as well as half-duplex FDD (H-FDD)
• Burst transmission format which support adaptive burst profiling– Transmission parameters, including the
modulation and coding schemes (burst-profiles)– Downlink Channel Descriptor (DCD) and Uplink
Channel Descriptor (UCD)– MAC management messages Downlink Map (DL-
MAP) and Uplink Map (UL-MAP)
14
802.16 PHY Introduction(cont.)
15
802.16 QoS Type
16
802.16 QoS Support
17
802.16 QoS Support(cont.)
18
802.16 Scheduling
IEEE 802.16
PMP (Point-to-Multipoint) Internet
BS
SS
SS
Mesh
Centralized Scheduling
Distributed Scheduling
Internet
BS
SS_A
SS_BSS_CSS_D
19
BS
SSB
SSA
SSC
SSE
SSD
SSH
SSI
SSG
SSF
SSJ
SSK
Internet
SSJSS
M SenderSS
L
SSJ
SSJSS
M Sender Receiver
MAC frame
MAC frame
Bandwidth request
Data flow
MAC frame
MAC frame
MAC frame
MAC frame
MAC frame
MAC frame
Centralized
• Congestion at BS• 1 SS active per time
slot• Longer route• Serious Delay
20
BS
SSB
SSA
SSC
SSE
SSD
SSH
SSI
SSG
SSF
SSJ
SSK
Internet
SSJSS
M SenderSS
L
Distributed
SSJ
SSJSS
M Sender Receiver
MAC frame
Contention for bandwidth
Data flow
MAC frame
MAC frame
MAC frameMAC frame
MAC frame
4
• Larger signaling cost
802.16 Mobility Management Middle Domain and Vertical Handoff
Reference: [1] J. Y. Hu, and C.-C. Yang, "On the Design of Mobility Management Scheme
for 802.16-based Network Environment," Proceedings of IEEE 62nd Semiannual Vehicular Technology Conference (VTC-2005 Fall), PP.25-28 Sept. 2005.
22
Introduction
GR: Gateway Router (Gateway of CIP or GFA of HMIP)
23
Introduction (cont.)
24
Introduction (cont.)
25
Middle-domain Mobility Management Scheme
26
Middle-domain Mobility Management Scheme (cont.)
27
Performance Evaluation-Quantitative Analysis by Simulation(1)
28
Performance Evaluation (cont.)-Quantitative Analysis by Simulation(2)
As soon as received stronger signal strength from other cell in the same layer, Horizontal Handoff
As soon as received the signal from lower layer, Downward Vertical Handoff
Upper Layer Networks : With larger coverage size and lower bandwidth
Lower Layer Networks : With smaller coverage size but higher bandwidth
C
B
A
33
Handoff Times (Total)
Handoff Times
050
100150200250
Speed-based Coverage-basedScheme Type
Total
hand
off (ti
mes)
.
High SpeedMedium SpeedLow Speed
34
Packet Loss (Total)
Packet Loss
0100200300400500
Speed-based Coverage-basedScheme Type
Total
Pack
et Lo
ss (pa
cket)
High speedMedium SpeedLow Speed
Quality of ServiceFramework, Routing, and Scheduling
Reference: [1] J. Chen, W. Jiao, and H. Wang, “A service flow management strategy for IEEE
802.16 broadband wireless access systems in TDD mode,” Proceedings of IEEE International Conference on Communications (ICC 2005), Vol. 5, PP. 3422-3426, May 2005.
[2] J. Chen, W. Jiao, and H. Wang, “An Integrated QoS Control Architecture for IEEE 802.16 Broadband Wireless Access Systems,” Proceedings of IEEE Global Telecommunications Conference (Globecom 2005), Vol. 5, PP. 3330-3335, Nov.-Dec. 2005.
[3] C.C. Yang, Y.T. Mai, and L.C. Tsai, “Cross-Layer QoS Support in the IEEE 802.16 Mesh Network,” Proceedings of 2006 Wireless Personal Multimedia Communications (WPMC 2006), PP.567-571, La Jolla, San Diego, California, Sept. 2006.
36
Introduction• In IEEE 802.16 standard, scheduling
algorithms for uplink and downlink bandwidth allocation in a single frame are undefined.
• There is no proposed bandwidth allocation solution considering uplink and downlink simultaneously.
37
Service Flow ManagementDSA: Dynamic Service AdditionDSC: Dynamic Service ChangeDSD: Dynamic Service Deletion
