Download 04 – Future Ad Hoc Network

ARSITEKTUR JARINGAN TERKINI
#4 FUTURE AD-HOC NETWORK
WIRELESS MESH NETWORK
GENERAL CHARACTERISTICS
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Communications network made up of radio nodes organized in a mesh topology
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Form of a wireless ad hoc network
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WMN do not require centralized access points to mediate the wireless connection
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WMN Multi-hop feature – increases the coverage area and link robustness of
existing Wi-Fi’s; ( if the correspondent nodes are not in the wireless transmission
range of each other)
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Dramatic increase in link quality just by shortening the distance between the nodes
GENERAL CHARACTERISTICS (CONT.)
• Dynamically
self-organized and self-configured systems (one node can
automatically establish and maintain the mesh connectivity)
• The
integration of WMNs with other networks such as Internet, IEEE 802.11,
802.15, 802.16, sensor networks etc can be accomplished
• WMNs offer multiple redundant communications paths throughout the network
and adaptive
• Wireless nodes: mobile or fixed
TYPE OF NODES
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Mesh Router
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contains additional routing functions to support mesh networking.
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improves the flexibility of mesh networking
usually equipped with multiple wireless interfaces built on either the same or
different wireless access technologies
Mesh Clients
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can also work as routers since they also have necessary functions for mesh
networking.
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gateway and bridge functions do not exist in these nodes.
usually have only one wireless interface as in Laptop/desktop PC, pocket PC,
PDA, IP phone, RFID reader, etc.
WMN ARCHITECTURE
• Based
on the functionality of the nodes the architecture of WMNs can be
classified into:
• Infrastructure mesh Architecture,
• Client mesh Architecture and
• Hybrid mesh Architecture
INFRASTRUCTURE MESH
• In
infrastructure mesh architecture, the mesh routers collectively provide a
wireless backbone infrastructure. Client node is passive in mesh infrastructure
INFRASTRUCTURE MESH (CONT.)
• Via
Ethernet links conventional clients with Ethernet interfaces can be
connected to mesh routers.
• If
the conventional clients have the same radio technologies as the mesh
routers then they can communicate directly with the mesh routers
• If different radio technologies are used then the clients communicate with their
base station that have Ethernet connections to mesh routers
CLIENT MESH
• Client meshing provides peer-to-peer networks among client devices. Here no
such mesh router is required. Client will act both like a mesh router by relaying
the packets and like an end user.
HYBRID ARCHITECTURE
• Mesh router provide the backbone of such network.
• With the help of network functionalities such as routing
and forwarding of
data packets, clients can actively participate in the creation of the mesh.
STANDARD
• IEEE 802.11s is the most relevant emerging standards for WMN technology
• Efforts are underway in several IEEE working groups, like 802.11, 802.15,
802.16, and 802.20, to define mesh standards.
WMN APPLICATION
• Transportation system
WMN APPLICATION (CONT.)
• Broadband Home Mesh
WMN APPLICATION (CONT.)
• Community Network
• Rural Area
WMN APPLICATION (CONT.)
• Military
• Emergency Response
PROTOCOL LAYERS
• Some of the factors that affect the capacity and performance of WMNs
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• In
network architecture,
network topology,
traffic pattern,
network node density,
number of channels used for each node,
transmission power level, and
node mobility.
order to develop the protocols we need to clearly understand the
relationship between the above factors and the capacity of WMNs.
ROUTING PROTOCOL
• General Ad-hoc routing protocol:
• Pro-active
• Re-active
• Hybrid
• Categories of routing protocol in WMN:
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Ad-hoc based (LQSR, SrcRR, MR-LQSR)
Controlled flooding (LOLS, MMRP, OLSR)
Traffic Aware (AODV-ST)
Opportunistic (ExOR, ROMER)
QUESTION
• Wireless
Mesh Network is a radical network form of the ever evolving
wireless network. The Mobile Ad-hoc network is also a form of the wireless
network. Compare and contrast the wireless mesh network and the Mobile Adhoc network that are the categories in the multi-hop wireless network !
COMPARISON WMN AND MANET
• There are various factors which can differentiate wireless mesh network from
Ad-hoc Network. The major differences between these two types of network
are the network topology and mobility of node
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Network topology: Ad- hoc network are called as the infrastructure less network
with a highly dynamic topology where as WMN have a relatively static network
topology
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Mobility of relay nodes: In Ad-hoc network the relay nodes have a higher
degree of mobility i.e. relay nodes aren't fixed whereas in WMN's the degree
of mobility of relay node is much lower than in Ad-hoc netowrks.
COMPARISON WMN AND MANET (CONT.)
• Deployment:
Some planning is required to deploy the WMNs whereas Adhoc network is easy to deploy.
• Infrastructure
requirement: Ad-hoc network is infrastructure less whereas
WMN has partial or fully fixed infrastructure.
• Energy constraints: In Ad-hoc network energy constraints is high whereas it is
low in the WMNs.