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Wiki2010 Unit 4
1. Wiki2010 Unit 4
f each other and usually with nodes sending data at a constant rate. Different protocols are then evaluated based on the packet drop rate, average
routing load, average end–to–end–delay, and other measures. The proposed solutions for routing protocols could be grouped in three categories:
proactive (or table–driven), reactive (or on–demand), and hybrid protocols. Even the reactive protocols have become the main stream for MANET
routing. In this chapter, we introduce some popular routing protocols in each of the three categories and for IPv6 networks
[Lee2009][Wiki2010a][Wiki2010c]. 1.3 Applications for MANET Ad hoc networks are suited for use in situations where infrastructure is either not
available or not trusted, such as a communication... Show more content on Helpwriting.net ...
So that when a packet needs to be forwarded, a route is already known and can be used immediately. Once the routing tables are setup, then data
(packets) transmissions will be as fast and easy as in the tradition wired networks. Unfortunately, it is a big overhead to maintain routing tables in the
mobile ad hoc network environment. Therefore, the proactive routing protocols have the following common disadvantages: 1. Respective amount of
data for maintaining routing information. 2. Slow reaction on restructuring network and failures of individual nodes. Proactive routing protocols
became less popular after more and more reactive routing protocols were introduced. In this section, we introduce three popular proactive routing
protocols – DSDV, WRP and OLSR. Besides the three popular protocols, there are many other proactive routing protocols for MNAET, such as CGSR,
HSR, MMRP and so on [Wiki2010c][Sholander2002]. 2.1 Destination–Sequenced Distance Vector (DSDV) Destination–Sequenced Distance–Vector
Routing (DSDV) is a table–driven routing scheme for ad hoc mobile networks based on the Bellman–Ford algorithm. It was developed by
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2. The Digital Signal Processing Applications
CHAPTER 1
INTRODUCTION
With advent of modern high–performance signal processing applications, high throughput is in great demand. Digital Signal Processing is perhaps the
most important enabling technology behind the last few decade's communication and multi–media revolutions. Most recent research in the digital signal
processing (DSP) area has focused on new techniques that explore parallel processing architectures for solutions to the DSP problems .DSP is used in
a numerous real time application related with the VLSI technology such as wireless communication, transmission system, multimedia, digital video,
digital audio and radar system. The field of DSP has always been driven by the advances in VLSI technologies. With the advances in... Show more
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Loop transformation techniques are applied extensively on loop intensive behaviors in design of area/energy efficient systems in the domain of
multimedia and signal processing applications. These are also commonly used during high–level synthesis for optimization purposes. One of the most
popular loop transformation techniques is retiming, which improves the performance of the system. Retiming relocates the delays or registers within a
circuit without altering the functionality. As relocating the delays or registers balances the critical path and reduces the states of the circuit.
CHAPTER 2
LITERATURE SURVEY
Graphical representation are efficient for investigating and analyzing the data flow properties of DSP system and for exploiting the inherent parallelism
among the different subtask. More importantly graphical representation can be used to map DSP algorithm to hardware implementation. This graphical
representation can build the gap between algorithmic description and structural implementation. It exhibits all parallelism and data driven properties of
the system and provide an insight into space and time tradeoffs.
2.1 DATA FLOW GRAPH
In Data Flow Graph (DFG) representation, the nodes represent computations and the directed edges represent data path and each edge has a
non–negative number of delays associated with it.
The DFG captures the data driven property of DSP algorithms where any node
4. The Routing Information Protocol ( RIP ) Essay
The Routing Information Protocol ( RIP )
INTRODUCTION:
I will summarize Request For Comments (RFC) 1058, Routing Information Protocol (RIP), by discussing RIPs basic algorithm/distance vector
algorithm, protocol, message format, protocol limitations, and new improvements to RIP.
RIP is very important to internetworking, since it passes information about routes between networks and hosts. It allows hosts and gateways to
exchange information for the purpose of computing routes.
BASIC ALGORITHM/DISTANCE VECTOR ALGORITHM:
RIP was designed to work with moderate sized networks, which used pretty much the same technology. It was not intended to work complex network
systems. RIP is widely used for routing traffic in the global ... Show more content on Helpwriting.net ...
In the following, the distance could be 4,5,6 and more. A–––––B–––––C / / | / / D–––E F–––––G | | | H | | / | I––––––––J | / | | K––––––––––L–––––M
In the above, the shortest path from A to M could be A–B–C–E–M, A–B–D–H–M, or A–G–J–L–M. There are two algorithms that find the shortest path:
the Bellman–Ford or Dijkstra algorithms. Once one of these algorithms are run, each node in the network will know the shortest path from itself to each
other node in the network.
The algorithm uses fixed "metrics" for route comparisons. The fixed metrics could be time delay, cost, or some other value used to compare routes. In
the following network, the numbers represent the cost to transverse the link.
A –––– 1 –––– B ––––– 2 ––––– C | | | |
| 3 2 1
| |
| |
5. 3 D –––– 3 –––– E –– 2 –– F
| /
| 1
| / G –––––––––– 3 –––––––––– H
In the above network the following would be:
Route Cost
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6. Pros And Disadvantages Of Routing
Networks are usually very humungous which makes the implementation of routing algorithms really tough. Hence there is a need to divide the
networks into autonomous systems. AS are groups of networks and routers which are under the control of a single admin. Routing can broadly be
divided into interior and exterior routing based on whether routing is inside an autonomous system or not.
There are three major/popular routing protocols being used.
Interior:
Routing Information Protocol (RIP)
Open Shortest Path First Protocol (OSPF)
Exterior
Border Gateway Protocol (BGP)
Routing Information Protocol (RIP) is the simplest and commonly used routing protocol in IP networks. It makes use of distance vector routing
technique and UDP for transport ... Show more content on Helpwriting.net ...
Disadvantages:
It has slow convergence. If a change is made in a network, it might take really long for the router to learn about it if they are not close by. To prevent
this max hop is introduced.
It is too simple in terms of metric
It might be unstable and leads to count to infinity problem. (loops of packets)
Scalability is an issue
Open Shortest Path First: OSPF is an interior routing protocol and is base on link state routing. It is comparatively more recent and efficient than the
widely used RIP. It also makes use of autonomous systems. It breaks the autonomous systems into one more level that is areas. It does not make use
of only hop count as metric. Metric based on type of service like minimum delay (rtt), maximum throughput, reliability, etc. It is competitively more
scalable than the RIP. It minimizes delay and maximizes throughput. It makes use of IP and has a value in the IP Header which is a 8 bit protocol field.
It has four different kind of links involved
Point to point
Virtual
Transient
7. Stub
It has five kinds of link state advertisement
Router link
Network link
Summary link to network
External
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8. Disadvantages And Disadvantages Of Wireless Networked And...
INTRODUCTION A network is collection of devices which are connected to each other for data exchange. Devices are linked with each other in
order to share resources, exchange files or allow electronic communications. These are interconnected for sharing data quickly and easily. A
network can be divided into wired and wireless networks. In wireless networks, there is no physical connection between devices or computers as
there are some sort of radio frequencies in air to transmit and receive data instead of using physical cables. In wireless networks, cables are used at
backbone and the computers are integrated with access points. Wireless networks work as same way as wired LAN using same protocols and
applications. Wireless technology has made easier the sharing of resources in a home or business simultaneously by multiple computer users without
exhibiting any additional or intrusive wiring. Wireless networks are easy to expand and inexpensive as compared to wired networks. The advantage of
wireless networks is that it data can be shared globally at all parts of the world. Wireless networks are flexible and so it is ideal for non–reachable
paces such as cross–river and mountains. The main disadvantage of wireless... Show more content on Helpwriting.net ...
when there is a need to transmit data from source to destination a route discovery process is initiated by the source. In this process, the network is
flooded with route request packets to create a suitable route from source to destination. The Routing table is also created on demand. Flooding is a
reliable method of passing information to all the nodes present in the network; however it uses bandwidth and cause delays in packet transmission but
decreases the control traffic overhead. After getting the best route, route establishment phase ceases with initiation of route maintenance phase which
keeps up valid routes and remove all the invalid routes thus reducing
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9. Bellman-Ford Deliverout Analysis
This part of your exam is worth 30 points.
Using the provided network diagram, write a program that finds the shortest path routing using the Bellman–Ford algorithm. Your program should
represent the fact that your node is U. Show how the iterative process generates the routing table for your node. One of the keys to your program will
be in determining when the iterative process is done. Deliverables
1.Provide an output that shows the routing table for your node after each iteration. Add a second table with two columns. One that shows the destination
from your node and the second column indicating the number of hops to reach that node.
OUTPUT:
The screenshot of the output of the running program is attached below. The distance... Show more content on Helpwriting.net ...
Below shown is how the output looks:
2.Provide a Word document with screenshots that explains how your program incorporates the Bellman–Ford algorithm. Ensure you explain and show
how you incorporated the iterative process and determined when the routing table for your node was optimum. You can incorporate your outputs into
this document; however, you must identify where in your source code you print the results required in deliverable 1 above.
This algorithm calculates the shortest path using the bottom–up approach. The Bellman Ford algorithm using a relaxation formula and calculates the
path between each edge and iterates for V–1 times using this formula to finally calculate the shortest path. We are assuming that there are no negative
weight cycle in the network.
It starts by calculating the shortest path between one node at first, then it checks for the path between two nodes, and so on proceeds in each iteration.
I have put the outer loop as V–1, where V is the total number of vertices that is present in the network. In our case, V=6. Therefore, there must be V–1,
which is 5 iterations to obtain the optimal shortest path to each of the node from the source node.
The below shown highlighted screenshot is the comparison relaxation formula used to check at each edge.
If we iterate through all the edges one more time, and still get the shortest path, this means that there is a negative weight cycle in the network. Hence,