Some places don’t have condition: Sponsor, Geography location, Facilities,… So, we need to build a wireless communication network without infrastructure to ensure that mobile device or e
Trang 1HA NOI UNIVERSITY OF SCIENCE AND TECHNOLOGY
ELECTRICAL AND ELECTRONICS ENGINEERING
Instructor: Dang Quang Hieu Class: ET-E4 K63 Name: Le Bao Ngoc
Student ID: 20182930
Trang 2TABLE OF CONTENTS
I) Overview of our project
II) Technical characteristic of MANETs
III) Routing of MANETs
IV) Implement MANETs on NS3
Trang 3I) OVERVIEW OF MY PROJECT
A.Overview
In recent years, with the dramatic improvement of data structures and algorithmic techniques with fundamental techniques of measurement with network
communication is the foundation of this field Before concluding this resource,
we have a report on subject that we learn and practice during this by making a simple server to test the loss propagation and do the survey with data rate of my server With the knowledge I have learned about , I will find the best form of my server and get the best simple server, avoid packet loss when doing and
researching a more complicated server
B.Development history
-Mobile Ad-hoc Network - MANET was formerly known as wireless network package, and funded, developed by DARPA in the early 1970s
-Then a new network: SUSAN (Adaptive Survivable Network) was proposed
published by DARPA in 1983 to support a larger, more robust network
stronger This time, Ad-hoc was used to describe a type of network such as
IEEE802.11 standard
Trang 4C.Purpose
-Build up a server with full infrastructure is so costly and not reasonable Some places don’t have condition: Sponsor, Geography location, Facilities,… So, we need to build a wireless communication network without infrastructure to ensure that mobile device or electronics can transmiss and get information conveniently over nodes and interconnection of server It is model of mobile ad hoc
netwook(MANETs)
MANETs architecture
D.Basic knowledge of MANETs
The Mobile Adhoc Network (MANET) consists of loosely interconnected router domains A MANET is characterized by one or more MANET network
interfaces, which are distinguished by their time-varying "asymmetric
accessibility" to neighboring routers These routers identify and maintain a
routing structure between them Routers can communicate over dynamic radio channels with asymmetric access, are mobile, and can join or leave the network
at any time In order to communicate with each other, adhoc nodes need to
Trang 5configure their network interface with local addresses that are valid in the area of that adhoc network Adhoc nodes may have to configure routable global
addresses to communicate with other devices on the Internet From an IP layer perspective, the MANET acts as a Layer 3 multi-hop network made up of links Therefore, each adhoc node in the MANET will act as a Layer 3 router to
provide connectivity to other nodes in the network Each adhoc node maintains routes to other nodes in the MANET and network routes to destination nodes outside of that MANET If connected to the Internet, MANETs become edge networks, meaning their borders are defined by edge-routers Due to the nature
of the links that make up the MANET, the adhoc nodes in the network do not share access for the multicast signaling single link Thus, in MANETs, there is
no reserve or dedicated multicast link and broadcast link
Test with MANET Routing(employs several multihop routing protocol, and packet queueing and enqueuing) with high data rate transmission and with low packetper second we can evaluate data transmission exactly through
AWGN Channel and AWWN+Rayleigh Channel
Result:
Received photo Sending photo
Trang 6E.Functional requirement of MANETs
1) Main function:
-MANETs is network that has seft-setup and be adaptive(tính tự thiết lập và dễ thích
nghi).All nodes of network can moving make topology structure of network change, but network nodes can detect the appearance of other one and process the connection
to transmiss information without management of host station or control
devices.Noticed that, besides detecting the connection of devices, it can types of device and respective description of this connected devices(laptop, PDA or
smartphone,….) so the calculating, storing, data transmission of each node is also different when compared these nodes.Specially, routing problems is very important because it is effect on MANET’s efficiency
Trang 7II) TECHNICAL CHARACTERISTIC OF MANETs
*Functional Characteristic:
1)Autonomous terminal(thiết bị tự trị đầu cuối): In MANETs, each end
point-mobile devices is self-control node(node tự trị) It can own function of host(máy chủ) and router(định tuyến)
2)Distributed operation(Phân chia hoạt động): All node of network have good
combination to each other, so it is easier for observing and manage to distribute to start-end point(thiết bị đầu cuối)
3)Multihop router(định tuyến đa lường): Based on different attribute connection
can set router on 1 hop or multihop over wirless communication range(phạm vi truyền tải không dây)
4)Dynamic network topology(cấu hình động): Because all nodes are mobile
nodes, so structure of network is easily change, so MANETs will routers
adapting and condition of propagation like mobile sample and mobile node.Thus, not only MANETs can operate inside mobile network but also it can access to public network(Internet)
5)Fluctuating link capacity(dao động về lượng liên kết): High bit error of
propagion is notice to MANETs network since inteference, multipath effects and its effect is less than ethernet channel(mạng có dây)
6)Light-weight terminals(tối ưu hóa thiết bị dầu cuối): All node need to
be optimized algorithms and operation
*Classify based on function:
1)Flat MANETs(Mạng MANETs đẳng cấp)
- Hierachical MANETs(Mạng MANETs phân cấp)
+This is the most commonly used model In this model, the network is
divided into domains, in each domain includes one or more clusters, each cluster
is divided into many nodes There are two types of nodes, master node and
normal node
++Master node: is the node that administers a router that is responsible for transferring data from nodes in the cluster to other nodes in the cluster and vice versa In other words, it acts as a gateway
Trang 8++Normal nodes: are nodes located in the same cluster It can connect to the nodes in the cluster or connect to other clusters through the master node
+With mechanisms on the network to use bandwidth resources more
efficiently because messages only have to be transmitted in 1 cluster However, managing node mobility becomes more complex The hierarchical network architecture is suitable for networks with low mobility
Hierachical MANETs Model
- Aggregate MANETs(Mạng MANETs kết hợp)
+Network = Zones, Zone = nodes
+Each node consists of two topology levels: low-level topology (node level), and high-level topology (zone level)
+Each node is characterized by: node ID and zone ID In a Zone can apply hierarchical architecture or hierarchical architecture
Aggregate MANETs Models
Trang 92)Classify based on protocol:
-Signal-hop:The singal-hop routing Manet network is the simplest type of hoc network model In it, all nodes are in the same coverage area, that is,
ad-nodes can connect directly to each other without the need for intermediate nodes
Trang 10Mobile-multihop Model
*Connection type and working mechanism:
1)Network topology connection types
-Mobile server network: in this topology, devices are only linked to a single server The network has inhomogeneous mobile devices
-The network has inhomogeneous mobile devices: in this topology, machines can link directly to each other within their coverage area
2) Operation mode
-IEEE-ad hoc mode: In this mode, mobile nodes communicate directly with each other without the need for any infrastructure In this mode, links can not be made over multiple hops
-Infrastructure mode: In this mode, the network includes fixed AP access points and mobile nodes participating in the network, performing communication through the access points In this mode, links can be made over multiple hops
Trang 11
III) ROUTING OF MANETs
*Routing type of MANETs:
-Bellman-ford routing:
+In the Bellman-Ford algorithm, every node maintains a routing table or
information matrix, its distance and information about its next node on the shortest path to any destination, where the distance is the shortest length from the node to the destination To update information about the shortest path, each node will
exchange frequently routing table with buttons next to it
+Based on the routing table from those neighboring nodes, any node knows the shortest distance from its neighbors to any destination node Therefore, for each destination node, the starting node will choose an intermediate node for the next hop such that the distance from it through the intermediate node to the destination node is minimal
network On-demand routing:
On-demand routing is known as DC (Diffusion Computation) as well used in
wireless networks In the On-demand routing scheme, a node constructs a path by interrogating all the nodes in the network Package query finds the IDs of the
intermediate nodes and stores them in the Path section When detecting the query, the destination node or the nodes that know the way to the destination answer the quality of query by responding “source routed” to the sender
-Area Routing:
This is a hybrid protocol between On-demand routing and an arbitrary protocol period existed In zone routing, each node defines its own zone when the node is at certain distance.The advantage of zone routing is scalability level when the storage need for the routing table decreases
Trang 12*Main routing protocol of MANETs:
-Proactive(định tuyến theo bảng):
+DSDV(Destination Sequence Distance
Vector)
+OLSR(Optimized Link State Routing)
-Reactive(định tuyến theo yêu cấu):
+DSR(Dynamic State Routing)
+AODV(Ad hoc On-Demand Distance Vector Routing)
Beside that, we can classify by to types: Link State Protocol, Distance Vector Protocol
1) DSDV(Destination Sequence Distance Vector)
-DSDV is a step-by-step distance vector routing protocol: Each node maintains a
routing table that stores the possible destination at the next hop of the route and the number of steps to reach the destination DSDV requires the node to periodically send broadcast routing information across the network
-The advantage of DSDV is that it ensures no closed routes by using sequence numbers to mark each path The sequence number indicates how "new" the route
is, the larger the number, the higher the degree of assurance (the R path is
considered better than R' if the sequence number of R is larger, in the case of the same number) order, then R must have a smaller number of steps) The sequence number will increase when node A finds that the route to destination D is broken, then node A advertises its route to node D with unlimited number of hops and the sequence number will increase
-DSDV depends on periodic broadcasts, so it takes time to collect information before the route is available This time is negligible for fixed-structured networks
in general (including wired networks), but for Ad hoc networks this time is
significant, which can cause packet loss before it can be detected reasonable
routing In addition, periodic advertising bulletins are also a cause of wasting network resources
Trang 132) OSLR(Optimized Link State Routing)
-It is proactive => Routes are prepared before needed
-It is optimize => Min flooding duplication in highly connected nets
-Ask only a subset of neighbors to forward link states This subset is “Multipoint Relay”(MPR) For instance, if X is your MPR, you are X’s “MPR selector” Each MPR has set of MPR selectors Each node sends link state to all its neighbors MPRs forward link state of MPR selectors Other neighbors use information to compute routing table, but it is not forward OLSR significantly reduces the link state control traffic
Example of OSLR:
+Node 5 has selcted 4,8 as MPR
+Node 5 sends a link state to2,3,4,6,7,8,11
+Nodes 2,3,6,7,11 uses the info but do not forward
+Node 4 uses the info and forwards it to 1,6,12,13
+Node 8 uses the info and forwards it to6,9,10
Trang 143) DSR(Dynamic State Routing)
-This is a protocol in the form of Distance Vector used in Manet When a network node needs to transfer data but does not know the path to a certain address, this network node initiates the process of route discovery (Route discovery) So DSR is
a passive protocol (Only updates the network state and finds the path when
required) One advantage of DSR is that no routing packets are sent periodically (since there is no need to update the network state as often – in contrast to the Link state protocol) The DSR is also capable of operating a one-way link Because DSR finds its way on demand, it is not suitable for high-capacity and highly mobile networks The DSR protocol also has two main operations: Route finding and path maintenance The following figure shows a simple example of DSR Routers A, B and C form a Manet network Router A and C are not connected to each other while both are connected to router
DSR Model
+During routing, routers maintain a list of the IDs of intermediate routers in recent search requests to avoid having to process the same (repeated) lookup request Lookup requests are ignored in cases where they have already been processed near that point and are identified as a duplicate request When a router receives a
request and realizes that its ID is already in the intermediate router list for that request, the request is ignored
+ Path maintenance occurs when the path becomes unusable because of the
unpredictable movement of routers (characteristic of MANET) Each router
manages all paths to forward packets, when a path fails, a packet of route error reporting (Route error) is immediately sent to the source router and the
corresponding path So the broken path will be ignored
Trang 154) AODV(Ad hoc On-Demand Distance Vector Routing)
-In AODV, route reply comeback on the reverse path(intermediate record node from which the first copy was received), so intermediate nodes update their following table, old entries are time out
-AODV supports only symmetric links If a source node moves, it must reinitiate route request If an intermediate node moves, all upstream nodes broadcast a link failure to their upstream neighbors until source node is reached But this protocol has disadvantage: Intermediate nodes may send more up-to-date but still state routes
-Example of AODV:
+Node 1 sends route request to 2,3,4
+Node 2 sends route request to 5,7
+Node 3 has 3-5-8-9-10 <Sequence#1>
+Node 4 has 4-6-8-9-10 <Sequence#4>
+Node 4 reponds
Trang 16
IV) IMPLEMENT MANETs ON NS3
A.Create network’s nodes on MANETs
Simulated mobile node model
The main network elements used to construct the protocol layer for each mobile node include: channel, network interface, radio propagation model, and protocols MAC, interface queue, link layer, ARP address resolution protocol model, and routing agent
There are currently several pre-installed protocols in NS3 namely DSDV, AODV, TORA,OLSR,DSR,…
Trang 17B.Shared media model
The wireless model is based on the shared media model (Ethernet in the air), illustrated in below figure All mobile nodes have one or more connected network interfaces
connected to a channel A channel is a specific band of radio frequencies with its own modulation and coding scheme Channels are orthogonal, which means that packets sent on one channel do not interfere with packets transmitted and received
on another channel
The basic operation is as follows, every packet sent or placed into the channel will
be received or copied by all mobile nodes connected to the same channel When the mobile node receives the packet, the node first considers whether it received the packet or not This is dictated by the radio broadcast model, based on the communication band, the distance the packet has traveled, and the amount of bit errors
Shared media model on NS3
C.Mobile node on MANETs
1)Operation of mobile node
Each mobile node uses a routing agent to calculate the route to other nodes in the
AD HOC network Packets are sent from the application and received by the routing component This part will decide the path of the packet to reach the
destination and attach this information to the packet The packet is then sent down
to the link layer The link layer uses the ARP address resolution protocol to decide
on the hardware address of the neighbor node and maps the IP address to the
Trang 18correct interface When the information is received, the packet is sent down the interface queue and waits for the signal from the MAC protocol When the MAC layer decides which packets can be sent into the channel, the packet is taken from the queue to the network interface and then sent out over the air channel The
packet is copied and delivered to all network interfaces at the time the first bit of the packet begins to arrive at the interface in the physical system Each network interface marks the packet with properties of the receiving interface and then
invokes the broadcast model
2)Topology of mobile node
-A mobile node is a basic nsNode object with additional functions such as
movement, the ability to transmit and receive on a channel allowing it to be used to create mobility, simulating a wireless environment The MobileNode class is
derived from the base class Node MobileNode is a split object The mobility
features including node movement, periodic location updates, maintaining
topology boundaries, etc are implemented in C++, while the network elements in the MobileNode itself (such as classifiers, dmux, LL, etc.) Mac, Channel, )
-A definite adhoc-routing agent that creates a network stack consisting of a link layer, an interface queue, a MAC layer, and a network interface with an antenna, using the radio broadcast model, links between components and connect the stack
to the channel
3)Moblie node’s movement creation on MANETs
-Mobilenode is designed to move in 3D space However, so far the 3rd dimension (Z) is not used, that is, the mobilenode is assumed to always move on a plane with
Z = 0 Then the mobilenode has X, Y, Z coordinates (= 0) is continuously adjusted
as the button moves There are 2 mechanisms for creating motion in mobilenodes
In the first method, starting from the location of the node and the destinations of those nodes can be explicitly set Control directives are usually in a separate
migration script file
-The initial location and destination for a mobilenode can be established using the following APIs:
$node set X_ <x1>
$node set Y_ <y1>
$node set Z_ <z1>
Trang 19D.Create protocol entities and traffic generators
Communication network models
-The communication models simulated in NS3 include two types of traffic
generators and simulated applications Communication generators use the UDP protocol to send packets, and simulation applications use the TCP protocol
-There are four types of traffic generators: exponential, pareto, CBR and file trace traffic generators
+Exponentially distributed traffic generator: generates traffic according to an
exponential on/off distribution During the “on” period, packets are sent at a fixed rate, and during the “off” period no packets are sent In addition, the on and off times are distributed according to an exponential distribution Packets have a constant size The exponential traffic generator is configurable to act as a Poisson process
+Parero distributed traffic generator: generate traffic according to Pareto on/off
distribution.This distribution is similar to the power on/off distribution, the only difference being the on and off time periods taken according to the Pareto
distribution These sources can be used to generate combined traffic representing dependencies
+Evenly distributed traffic generator - CBR: generates traffic at a specified rate
determined The packet size is constant In addition, a number of random
oscillations are performed between the starting intervals of the packets
+Trace file traffic generator: generates traffic according to a trace file that
determines the time to transmit and stop transmitting packets and other parameters based on data obtained from the real network, recorded in the trace file
Trang 20E.Create motion patterns following templates
-In AD HOC network simulation, migration patterns play a very important role They need to accurately represent the possible contexts of the network and help determine the correct performance of the protocols before being implemented in practice For wireless networks, two types of migration models are used, the trace model and the synthetic model Trace models are patterns of movement observed
in the real system Trace models provide accurate information, especially when they involve many participants and the observation period is long enough
However, with the new network environment, AD HOC networks are not easily traceable In this case it is necessary to use synthesize models
-Synthesize models attempt to represent the behavior of mobile nodes without resorting to a trace model by statistically describing node movements Each node is assigned an algorithm to randomize the movement The network migration pattern
is the set of migrations from applying the migration model to one or more nodes Two typical migration models that emulate AD HOC networks are the Random Waypoint and the Random Walk
*General diagram of simulation:
Trang 21V)WIRELESS CHANNEL
A.PARAMETERS OF WIRELESS CHANNEL
-BANDWIDTH (Unit: KHz/MHz): The space allowing how much amount of
data should be transferring Higher the bandwidth the more will data transfer and receiving rate
-ARIER FREQUENCY (Unit: KHz/MHz): In telecommunications, a carrier
wave, carrier signal, or just carrier, is a waveform that is modulated with an information-bearing signal for the purpose of conveying information \
B.TWO TYPES OF WIRELESS CHANNEL
-Communication channel means a physical transmission medium Channels is used to convey an information signal A defining characteristic of the mobile wireless channel is the variations of the channel strength over time and over frequency The variations can be roughly divided into two types:
+ Large-scale fading, due to path loss of signal as a function of distance and shadowing by large objects such as buildings and hills