Adapting BitTorrent to Wireless Ad-Hoc Networks

 BitTorrent is one of the Internet's most e cient content distribution protocols. It is known to perform very well over the wired Internet where end-to-end performance is almost guaranteed. However, in wireless ad hoc networks, many constraints appear as the scarcity of resources and their shared nature, which make running BitTorrent with

its default con guration not lead to best performances. To these constraints it adds the fact that peers are both routers and end-users and that TCP-performance drops seriously with the number of hops. 

We show in this work that the neighbor selection mechanism in BitTorrent plays an important role in determining the performance of the protocol when deployed over a wireless ad hoc network. It is no longer e cient to choose and treat with peers independently of their location. A rst solution is to limit the scope of the neighborhood. In this case, TCP connections are fast but there is no more diversity of pieces in the network: pieces propagate in a unique direction from the seed to distant peers. This prohibits peers from reciprocating data and leads to low sharing ratios and suboptimal utilization of network resources. To recover from these impairments,

we propose an enhancement to BitTorrent which aims to minimize the time to download the content and at the same time to enforce cooperation among peers. Our solution considers a restricted neighborhood to reduce routing overhead and to improve throughput, while establishing few connections to remote peers to improve diversity of pieces. With the help of extensive NS-2 simulations, we show that these enhancements

to BitTorrent signi cantly improve the le completion time while fully pro ting from the incentives implemented in BitTorrent to enforce fair sharing


full download paper is here
Full code is on https://github.com/ebine/bittorrent-ns2

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Simulation and Analysis of Routing Protocol under CBR and TCP Traffic Source in NS2

In this project we are going to investigate the performance of some routing protocols for Ad-Hoc Networks under CBR and TCP traffic source. The behaviors of TCP still have not well understood in the multi-hop wireless networks. Through this paper we are able to find that how TCP will react under different network conditions. In this traffic and mobility scenarios play an important role in evaluating the performance of these networks, despite comment and belief from various researches on TCP's weaknesses on MANET. As Mobile Ad-Hoc Network (MANET) support multi-hops wireless communication without using any existing infrastructure or centralized administration. And support continuous changing network topology, provides distributed operations, easily deployment and thus, routing becomes a challenging task. A different flavor of reactive and proactive routing protocols are analyze with varying network conditions and speed to find an optimized route from a source to some possible destination. This paper presents how routing protocol will behave in less and more stressful condition, performance of mobile ad hoc network routing protocol such as AODV, DSDV, DSR, to simulate the above said protocol on the base of normalize routing load, throughput, Average End-to-End to delay, packet loss and packet delivery fraction. For our simulation we used a discrete event simulator known as Network Simulator version 2.34.

The code is here in github : https://github.com/ebine/cbr-ftp-comparison-/blob/master/xgragh.tcl

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TOP 10 extenstions for google chrome

Below I list the top 10 Chrome extensions to get you started.

1. AdBlock - Some claim that ad blocking is killing the free Web, others say that ad blockers are simply killing bad advertisers. Whatever your position, anyone looking for an equivalent of Greasemonkey for Chrome should start with the AdBlock Chrome extension. It strips out most ads from the majority of websites, making for a cleaner, faster (and, thanks to blocked autoplaying video ads, quieter) browsing experience

2. Chrome SEO

Current features: show number of Pages Indexed on Google, Yahoo...; show Page Rank by Alexa, Google...; show IP Address, Server Location...; Back-links; Social Bookmarks; Cached Versions.

3. Google Mail Checker Plus

Displays the number of unread messages in your Gmail and Google Apps inbox. Preview mail, read, delete, archive and mark as spam!
Many users admit it's better than the more-popular Google Mail Checker extension.

4. IE Tab- Some sites are optimized to run exclusively in Internet Explorer, especially Microsoft products like Outlook Web Access. Don't give up that native IE Web functionality 99just because you're using Chrome. The IE Tab Chrome Extension creates a virtual IE browser within Chrome, so you get all the Internet Explorer-ness without running two different browsers.

5. Docs PDF/PowerPoint Viewer - If Chrome has one glaring weakness, it's that it doesn't always handle PDF links very well. (I've had to kill more than a few stalled Chrome tabs that unknowingly tried to open PDF online forms.) The Docs PDF/PowerPoint Viewer Chrome extension sends any PDF or PowerPoint Web link to Google Docs, where the document can be read, surfed, printed or saved quickly and easily.

6. FastestChrome - FireFox users will call this Chrome extension FastestFox for Chrome, which is appropriate, since the two plug-ins share the same creator. The FastestChrome extension enhances Web searches. Highlight any word on a page to get a definition of the term, or launch a search for the text. On Google search results, additional results pages are automatically loaded so you can just keep scrolling. Relevant results from other search engines and sites -- like Amazon and Wikipedia -- are interlinked into standard Google search results. On Wikipedia pages, related articles are automatically loaded into the left-hand column. If you perform any amount of web research on a regular basis, the FastestChrome extension gets very addictive, very fast.

7. GooglePreview - The GooglePreview Chrome Extension is simple: It adds a thumbnail to the left of any Google search result showing a snapshot of the listed website. This is very helpful when you're looking for a site you visited but didn't bookmark, as the thumbnail image can help jog your memory. Also, if there are (ahem) unsavory images on the page, you'll know before you open the link

8 . Firebug Light

 While it might only really apply to web developers, Firebug Light is nevertheless one of the most essential tools you can think of to have alongside your Chrome installation if editing HTML and CSS is you cup of tea. Why's that? Firebug Light allows you to quickly pull up the full details of a given page, split into sections for easier scanning.

9. Sexy Undo Close Tab

Reopening a closed tab in Chrome is super-easy, right? Just hold down Control, jam Shift, and hit "T." Voila. Up pops the tab you were last viewing.Now, what if you wanted to check out a tab that you were viewing, say, eight tab-closes ago? Would you really want to pull up that many old tabs just to get to the single piece of information you sought? Dare you try to navigate your way through Chrome's history, which can itself be mucked up and confusing based on the browsing you've done through any number of individual tabs?

 10 . Xmarks
Xmarks the spot, as the joke goes. In this case, the "spot" is, "your comprehensive collection of bookmarks that you don't want to lose every time you hop to another system or web browser." And you won't, not with this awesome extension. For Xmarks gives you an automatic method for synchronizing your browser bookmarks to a centralized server-the "cloud," as it were-which you can then pull down onto any applicable browser installation… anywhere

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