DOC PREVIEW
WUSTL CSE 574S - Wireless Mesh and Multi-Hop Relay Networks

This preview shows page 1-2-23-24 out of 24 pages.

Save
View full document
View full document
Premium Document
Do you want full access? Go Premium and unlock all 24 pages.
Access to all documents
Download any document
Ad free experience
View full document
Premium Document
Do you want full access? Go Premium and unlock all 24 pages.
Access to all documents
Download any document
Ad free experience
View full document
Premium Document
Do you want full access? Go Premium and unlock all 24 pages.
Access to all documents
Download any document
Ad free experience
View full document
Premium Document
Do you want full access? Go Premium and unlock all 24 pages.
Access to all documents
Download any document
Ad free experience
Premium Document
Do you want full access? Go Premium and unlock all 24 pages.
Access to all documents
Download any document
Ad free experience

Unformatted text preview:

23-1©2010 Raj JainCSE574sWashington University in St. LouisWireless Mesh and Wireless Mesh and MultiMulti--Hop Relay Hop Relay NetworksNetworksRaj Jain Washington University in Saint LouisSaint Louis, MO [email protected]/Video recordings of this lecture are available at:http://www.cse.wustl.edu/~jain/cse574-10/23-2©2010 Raj JainCSE574sWashington University in St. LouisOverviewOverview Multi-Hop Relay Networks 802.16j Mobile Multi-hop Relay (MMR) 802.15.5 WPAN Mesh Networking 802.11s Mesh Networks: Applications Wi-Fi Mesh Products23-3©2010 Raj JainCSE574sWashington University in St. LouisMultiMulti--Hop NetworksHop Networks Relay: Dedicated carrier owned infrastructure, Tree based topology. One end of the path is the base station Mesh: Routing by subscriber equipment, Multiple connections, mesh topologyRef: http://en.wikipedia.org/wiki/Mesh_networking23-4©2010 Raj JainCSE574sWashington University in St. LouisMultiMulti--Hop Relay NetworksHop Relay Networks Next generation networks need very high data rates Data rate ∝ 1/distance ⇒ High density of cell towers ⇒ High cost Multi-hop Networks have fixed infrastructure ⇒ Do not need complex routing techniques Relays are low-cost low transmit power and have no connection to wired infrastructure More capacity due to shorter distances and frequency reuse Goal: High capacity and coverage (not absence of infrastructure)BaseRelayMobile Host23-5©2010 Raj JainCSE574sWashington University in St. LouisCoverage ExtensionCoverage Extension Side streets can be covered by relays A series of relays can be used to forward traffic to base Relaying either in time domain or frequency domainBaseRelayMobile23-6©2010 Raj JainCSE574sWashington University in St. LouisThroughput EnhancementThroughput Enhancement Virtual Antenna Arrays Multiple cooperating relays act as distributed MIMO Challenges: Synchronization, Sharing of Channel State Information3×2 MIMO23-7©2010 Raj JainCSE574sWashington University in St. LouisiCARiCAR Integrated Cellular and Ad-Hoc Relaying System Relaying stations are used to divert traffic from congested cells to nearby lightly loaded cells Even existing calls can be moved ⇒ Secondary relaying23-8©2010 Raj JainCSE574sWashington University in St. Louis802.16j Mobile Multi802.16j Mobile Multi--hop Relay (MMR)hop Relay (MMR) Three types of Relays: Fixed, Nomadic (special events, Indoor), Mobile Relays (Trains)23-9©2010 Raj JainCSE574sWashington University in St. Louis802.16j Technical Issues802.16j Technical Issues Centralized vs. distributed control: Functional division between Base and Relay Scheduling Radio Resource management Power Control Call Admission and Traffic Shaping Policies QoS: Network wide load balancing, Congestion control Security ManagementNote: Routing is not an issue with fixed relays23-10©2010 Raj JainCSE574sWashington University in St. LouisMultiMulti--Hop Relay Networks: SummaryHop Relay Networks: Summary Relay concept applies to Cellular Networks and to Wireless Access Relays can help overcome obstacles Relays help improve the capacity by decreasing the distance Relays help decrease the cost since they are much cheaper than base stations Routing with fixed relays is simple Increasing delays ⇒ Number of hops must be limited to two or three Distributed MIMO ⇒ Improvement in data rates23-11©2010 Raj JainCSE574sWashington University in St. LouisMesh NetworksMesh Networks WPAN Mesh: 802.15.5 WLAN Mesh: 802.11s23-12©2010 Raj JainCSE574sWashington University in St. Louis802.15.5 WPAN Mesh Networking802.15.5 WPAN Mesh Networking Goal: Range Extension, Routing Redundancy Issues:¾ Handle Multiple Master devices¾ Handle multiple super frame coexistence¾ Fair sharing of channel time¾ Minimal changes to 802.15.3 and 802.15.4Mesh Control and Data pathPiconets23-13©2010 Raj JainCSE574sWashington University in St. Louis802.11s Mesh Networks: Applications802.11s Mesh Networks: ApplicationsCMTSSSMSOs/CLEC/Municipal10/100/1000 MbpsInternet100/1000 MbpsEnterprise CampusEmergency ResponseHome Networks23-14©2010 Raj JainCSE574sWashington University in St. Louis802.11s Device Classes802.11s Device Classes Stations (STA): Non-mesh capable station Mesh Points (MP): Mesh capable station Mesh AP (MAP): MP + AP Mesh Portal (MPP): Entry/exit to wired network. Support transparent bridging, address learning, and bridge-to-bridge communication (spanning tree etc). Root Portal: MPP configured for topology building. Elected to become the root of the default forwarding tree MPMAPMPPSTABridge/RouterMPMPRef: http://en.wikipedia.org/wiki/IEEE_802.11s23-15©2010 Raj JainCSE574sWashington University in St. Louis802.11s Hybrid Wireless Mesh Protocol802.11s Hybrid Wireless Mesh Protocol Two Configurations: With Root Portal and Without Root PortalRoute Discovery: W/O Root Portal: ¾ On-demand Radio Metric AODV (RM-AODV)Cost = Amount of air time consumed per packet transmission¾ Radio Aware OLSR Path Selection Protocol (Optional)Frequency of LS forwarding is reduced with hops(Fish eye state routing) W Root Portal: Most of the traffic is to the root.¾ Proactive. Tree based distance vector routing.23-16©2010 Raj JainCSE574sWashington University in St. LouisCommon Channel FrameworkCommon Channel Framework All stations use a single control channel Stations dynamically select the data channel They announce it on the common control channel using RTX/CTX (Not RTS/CTS) packets23-17©2010 Raj JainCSE574sWashington University in St. Louis802.11s Examples802.11s Examples59710643218X59710643218X4->94 sends RREQ9 sends RREP4->X4 sends RREQNo Resp ⇒ 4 forwards to MPP 123-18©2010 Raj JainCSE574sWashington University in St. Louis802.11s Examples802.11s Examples59710643218X59710643218X4->X4 forwards to MPP1MPP1 sends to X4->94 forwards to MPP1MPP1 sends to 99 Issues RREQ4 sends RREP23-19©2010 Raj JainCSE574sWashington University in St. LouisWiWi--Fi Mesh ProductsFi Mesh Products LocustWorld.com¾ MeshAP S/W: Freeware from locustworld.com. Allows computers to act as wireless routers.¾ Uses AODV protocol. Problem of false DVs.¾ MeshBox: Complete hw/sw package¾ MeshBox 2 or MexBox: Uses two Wi-Fi radio modules. Successive routers could share a channel, e.g., 1+2, 2+3, 3+1 among three routers. FireTide Network: ¾ HotPort 4.9 GHz Public Safety Mesh Nodes, ¾


View Full Document

WUSTL CSE 574S - Wireless Mesh and Multi-Hop Relay Networks

Documents in this Course
Figures

Figures

11 pages

Concept

Concept

8 pages

Mobile IP

Mobile IP

30 pages

Load more
Download Wireless Mesh and Multi-Hop Relay Networks
Our administrator received your request to download this document. We will send you the file to your email shortly.
Loading Unlocking...
Login

Join to view Wireless Mesh and Multi-Hop Relay Networks and access 3M+ class-specific study document.

or
We will never post anything without your permission.
Don't have an account?
Sign Up

Join to view Wireless Mesh and Multi-Hop Relay Networks 2 2 and access 3M+ class-specific study document.

or

By creating an account you agree to our Privacy Policy and Terms Of Use

Already a member?