Wireless Kernel Tweaking
or how B.A.T.M.A.N. learned to fly
Kernel hacking definitely is the queen of coding but in order to bring mesh routing that one vital step further we had to conquer this, for us, unchartered territory. Working in the kernel itself is a tough and difficult task to manage, but the results and effectivity to be gained justify the long and hard road to success. We took on the mission to go down that road and the result is B.A.T.M.A.N. advanced which is a kernel land implementation of the B.A.T.M.A.N. mesh routing protocol specifically designed to manage Wireless MANs.
Research Inventy : International Journal of Engineering and Scienceresearchinventy
Research Inventy : International Journal of Engineering and Science is published by the group of young academic and industrial researchers with 12 Issues per year. It is an online as well as print version open access journal that provides rapid publication (monthly) of articles in all areas of the subject such as: civil, mechanical, chemical, electronic and computer engineering as well as production and information technology. The Journal welcomes the submission of manuscripts that meet the general criteria of significance and scientific excellence. Papers will be published by rapid process within 20 days after acceptance and peer review process takes only 7 days. All articles published in Research Inventy will be peer-reviewed.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
Research Inventy : International Journal of Engineering and Scienceresearchinventy
Research Inventy : International Journal of Engineering and Science is published by the group of young academic and industrial researchers with 12 Issues per year. It is an online as well as print version open access journal that provides rapid publication (monthly) of articles in all areas of the subject such as: civil, mechanical, chemical, electronic and computer engineering as well as production and information technology. The Journal welcomes the submission of manuscripts that meet the general criteria of significance and scientific excellence. Papers will be published by rapid process within 20 days after acceptance and peer review process takes only 7 days. All articles published in Research Inventy will be peer-reviewed.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
Delay efficient broadcast scheduling for critical event monitoring in wireles...eSAT Journals
Abstract Wireless sensor networks are expected to work for a longtime without replacing the batteries frequently. In critical event monitoring applications in wireless sensor networks only a small number of packets need to be transmitted most of the time, when a critical event occurs in the monitoring area and is detected by a sensor node, a message is needed to be broadcast to the other nodes as soon as possible. After that, the sensor nodes can warn users nearby to flee or take some response to the event. As sensor nodes for monitoring an event are expected to work for a long time without recharging their batteries, sleep scheduling method is needed during the monitoring process. But they are only significantly reducing the energy consumption and the broadcasting delay increases. The sleep scheduling scheme in this work could essentially decrease the communication latency of alarm broadcasting from any node in WSN and the energy of all of the sensor nodes in the network is fully utilized, which in turn increases the network lifetime.
Delay efficient broadcast scheduling for critical event monitoring in wireles...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
AN EVALUATION ON SELFISH BEHAVIOUR ATTACK AND JELLYFISH ATTACKS UNDER AODV RO...ijfcstjournal
The Mobile Adhoc network applications are increasing every day due to the properties like infrastructure less nature, dynamic topology and multihop network. A set of rule that govern which path is to be followed from the source node to destination node is called routing protocol which can be further divided into number of other categories like proactive and reactive. This paper discusses the AODV, a kind of reactive
routing protocol, for its study. But MANETs is also vulnerable to number of attacks due to its nature. A lot of work has been done to make it more secure. The work that is addressed in this paper is the selfish node attack and jellyfish attack on AODV routing protocol. The selfish node attack is a kind passive attack in which node does not participate in routing process by not forwarding the packets. And jellyfish attack is
the sub type of black hole attack that delays or drops the packets for certain amount of time. This paper studies all the three types of jellyfishattack: Jellyfishreorder attack, jellyfishperiodic dropping attack and jellyfishdelay variance attack. In this work we study the impacts of some of the attacks on network under a short term military rescue mission like scenario. We will do a comparative analysis of three kinds of JellyfishAttacks with selfish Behaviour Attack under AODV routing protocol. The analysis will be made with respect to different network sizes and under the presence of different number of attackers in the network. The impact on the performance will be measured with suitable metrics to understand the nature of different attacks.
The BonFIRE architecture was presented at the TridentCom Conference. These are the slides for the paper, which describes the key components and principles of the architecture and also some specific features offered to experimenter that are not available elsewhere.
Networking With Windows Server 2003 Part 2 By Yapa WijeratneYapa
Networking With Windows Server 2003 Part 2
covers basics of networking steps in Windows Server 2003. It covers essential aspects of networking & simply explains how to make small network by yourselves.By Yapa Wijeratne
Cluster Head and RREQ based Detection and Prevention of Gray hole and Denial ...IJSRD
Wireless sensor network is a type of network which have no communications pattern for communication between nodes, any node can easily join the network and leave the network so attacks are more probable. Gray hole is one of such attacks and it is tough to detect since malicious node switches behavior between normal node and malicious node. For detection and prevention of gray hole attacks our proposed technique is based on Cluster head and RREQ based approach in WSN. In our proposed technique we select a node which has the highest energy as a cluster head and remaining node are marked as work as cluster member. For each node we decide a threshold for sending RREQ if any node generate RREQ more than threshold then we check its RREP threshold value if it’s less than one than cluster head will conclude this node as a malicious node and broadcast its node id so that all other nodes also mark it as malicious node and drop the request arrive from this malicious node and for gray hole detection.
Secure Scan Design Using Redundant Scan RegisterIDES Editor
Cryptographic VLSI chip has a significant role to
resist the attacks which is the growing customer concern of
hardware security. Redundancy introduces a great amount of
randomness & non linearity in any kind circuitry
(combinational or sequential). We introduce a new type of
redundancy in sequential circuits to make redundant scan
registers that are indistinguishable with the original scan
registers. They are sequentially undetectable as well as
redundant, which makes it highly secured. The approach is
only to replace the original scan registers to modified
redundant scan registers called RScR.
Delay efficient broadcast scheduling for critical event monitoring in wireles...eSAT Journals
Abstract Wireless sensor networks are expected to work for a longtime without replacing the batteries frequently. In critical event monitoring applications in wireless sensor networks only a small number of packets need to be transmitted most of the time, when a critical event occurs in the monitoring area and is detected by a sensor node, a message is needed to be broadcast to the other nodes as soon as possible. After that, the sensor nodes can warn users nearby to flee or take some response to the event. As sensor nodes for monitoring an event are expected to work for a long time without recharging their batteries, sleep scheduling method is needed during the monitoring process. But they are only significantly reducing the energy consumption and the broadcasting delay increases. The sleep scheduling scheme in this work could essentially decrease the communication latency of alarm broadcasting from any node in WSN and the energy of all of the sensor nodes in the network is fully utilized, which in turn increases the network lifetime.
Delay efficient broadcast scheduling for critical event monitoring in wireles...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
AN EVALUATION ON SELFISH BEHAVIOUR ATTACK AND JELLYFISH ATTACKS UNDER AODV RO...ijfcstjournal
The Mobile Adhoc network applications are increasing every day due to the properties like infrastructure less nature, dynamic topology and multihop network. A set of rule that govern which path is to be followed from the source node to destination node is called routing protocol which can be further divided into number of other categories like proactive and reactive. This paper discusses the AODV, a kind of reactive
routing protocol, for its study. But MANETs is also vulnerable to number of attacks due to its nature. A lot of work has been done to make it more secure. The work that is addressed in this paper is the selfish node attack and jellyfish attack on AODV routing protocol. The selfish node attack is a kind passive attack in which node does not participate in routing process by not forwarding the packets. And jellyfish attack is
the sub type of black hole attack that delays or drops the packets for certain amount of time. This paper studies all the three types of jellyfishattack: Jellyfishreorder attack, jellyfishperiodic dropping attack and jellyfishdelay variance attack. In this work we study the impacts of some of the attacks on network under a short term military rescue mission like scenario. We will do a comparative analysis of three kinds of JellyfishAttacks with selfish Behaviour Attack under AODV routing protocol. The analysis will be made with respect to different network sizes and under the presence of different number of attackers in the network. The impact on the performance will be measured with suitable metrics to understand the nature of different attacks.
The BonFIRE architecture was presented at the TridentCom Conference. These are the slides for the paper, which describes the key components and principles of the architecture and also some specific features offered to experimenter that are not available elsewhere.
Networking With Windows Server 2003 Part 2 By Yapa WijeratneYapa
Networking With Windows Server 2003 Part 2
covers basics of networking steps in Windows Server 2003. It covers essential aspects of networking & simply explains how to make small network by yourselves.By Yapa Wijeratne
Cluster Head and RREQ based Detection and Prevention of Gray hole and Denial ...IJSRD
Wireless sensor network is a type of network which have no communications pattern for communication between nodes, any node can easily join the network and leave the network so attacks are more probable. Gray hole is one of such attacks and it is tough to detect since malicious node switches behavior between normal node and malicious node. For detection and prevention of gray hole attacks our proposed technique is based on Cluster head and RREQ based approach in WSN. In our proposed technique we select a node which has the highest energy as a cluster head and remaining node are marked as work as cluster member. For each node we decide a threshold for sending RREQ if any node generate RREQ more than threshold then we check its RREP threshold value if it’s less than one than cluster head will conclude this node as a malicious node and broadcast its node id so that all other nodes also mark it as malicious node and drop the request arrive from this malicious node and for gray hole detection.
Secure Scan Design Using Redundant Scan RegisterIDES Editor
Cryptographic VLSI chip has a significant role to
resist the attacks which is the growing customer concern of
hardware security. Redundancy introduces a great amount of
randomness & non linearity in any kind circuitry
(combinational or sequential). We introduce a new type of
redundancy in sequential circuits to make redundant scan
registers that are indistinguishable with the original scan
registers. They are sequentially undetectable as well as
redundant, which makes it highly secured. The approach is
only to replace the original scan registers to modified
redundant scan registers called RScR.
PLNOG 17 - Krzysztof Wilczyński - EVPN – zwycięzca w wyścigu standardów budow...PROIDEA
W wyścigu wielu technologii i standardów budowy sieci Data Center oraz Data Center Interconnect, EVPN zdaje się być tym, który wysunął się na prowadzenie. W ramach sesji odpowiemy sobie na pytanie gdzie EVPN jest w tej chwili na tle innych technologii, gdzie go stosować, na co zwracać uwagę podczas wdrożenia.
Data Communications,Data Networks,computer communications,multiplexing,spread spectrum,protocol architecture,data link protocols,signal encoding techniques,transmission media,asynchronous transfer mode,routing,cellular networks,lan,wan,man
The following resources come from the 2009/10 BSc in Computer and Network Technologies (course number 2ELE0072) from the University of Hertfordshire. All the mini projects are designed as level two modules of the undergraduate programmes.
The objectives of this module are to Demonstrate within a private network environment:
• The implementation of a wireless local are networks (WLANs) topology with diverse physical parameters
• The real-time performance evaluation of the individual WLAN transmission characteristics in the presence of standard transport protocols.
This mini-project involves the implementation of an “infrastructure” wireless network, the generation and transmission of packets and the measurement of network performance for TCP transport protocols by means of the “Wireshark” benchmarking tool. Parameters most likely to affect network performance such as the transmission medium’s signal-to-noise ratio, the propagating signal’s latency and jitter and the packet loss rate will be determined.
Seven years ago at LCA, Van Jacobsen introduced the concept of net channels but since then the concept of user mode networking has not hit the mainstream. There are several different user mode networking environments: Intel DPDK, BSD netmap, and Solarflare OpenOnload. Each of these provides higher performance than standard Linux kernel networking; but also creates new problems. This talk will explore the issues created by user space networking including performance, internal architecture, security and licensing.
Hello!
Welcome to our CCNA Training (R&S) 200-125 series in Urdu.
CCNA stands for Cisco Certified Network Associate. R&S means Routing & Switching. The Exam Code of this course in 200-125. It's the basic course of CCNA track. If you want to start any certification like CCNA Security then you must pass the exam of CCNA R&S first. The exam time of this course is 90-120 mints. Here 90 mints time is for English Speaking Person & 120 mints time for non-native speakers. Total Marks of Exam is 1000 & Passing mark is 860. Number of Questions in Exam is 55 to 65.
You can book the exam from Pearson testing service.
Here is the link of Exam website.
https://home.pearsonvue.com
EZXPRT an IT Trainnig Institute offers CISCO , Microsoft, Vmware, Huawei, Trainings in Rawalpindi, Lahore, Mirpur and Wah Cant campuses,
We offer ONLINE Live and Recorded Training's on demand and we provide services of Career Counseling, Motivation etc.
For more details you may contact
WhatsApp/Call :+923-23-4699123
shafqaat@ezprt.com
www.ezxprt.com
www.facebook.com/ezxprt
www.youtube.com/c/ezxprt
EZXPRT an IT Trainnig Institute offers CISCO , Microsoft, Vmware, Huawei, Trainings in Rawalpindi, Lahore, Mirpur and Wah Cant campuses, We offer ONLINE Live and Recorded Training's on demand and we provide services of Career Counseling, Motivation etc.
.
CCNA stands for Cisco Certified Network Associate. R&S means Routing & Switching. The Exam Code of this course in 200-125. It's the basic course of CCNA track. If you want to start any certification like CCNA Security then you must pass the exam of CCNA R&S first. The exam time of this course is 90-120 mints. Here 90 mints time is for English Speaking Person & 120 mints time for non-native speakers. Total Marks of Exam is 1000 & Passing mark is 860. Number of Questions in Exam is 55 to 65.
You can book the exam from Pearson testing service.
Here is the link of Exam website.
https://home.pearsonvue.com
For more details you may contact
WhatsApp/Call :+923-23-4699123
shafqaat@ezprt.com
www.ezxprt.com
www.facebook.com/ezxprt
www.youtube.com/c/ezxprt
L2/L3 für Fortgeschrittene - Helle und dunkle Magie im Linux-NetzwerkstackMaximilan Wilhelm
Der Switch in meinem Linux-Rechner - was ist eine Bridge und wie benutze ich sie? Was sind VLANs und gar vlan-aware-Bridges? Fesselspiele mit Netzwerkkabeln - Bonding/Channel/Trunks mit und ohne LACP.
Auf Layer 3 tauchen wir ab in die Routingtabellen jedes Linux-Systems (derer gibt’s immer mindestens 3) sowie fortschrittlichere Magie wie policy-based Routing, VRFs und Network Namespaces; Beispiele aus dem echten Leben zeigen, wozu das alles gut ist und wie man damit arbeitet.
Minimizing mobiles communication time using modified binary exponential backo...IJCNCJournal
The domain of wireless Local Area Networks (WLANs) is growing speedily as a consequence of
developments in digital communications technology. The early adopters of this technology have mainly
been vertical application that places a premium on the mobility offered by such systems. Examples of these
types of applications consist of stocking control in depot environments, point of sale terminals, and rental
car check-in. Furthermore to the mobility that becomes possible with wireless LANs; these systems have
also been used in environments where cable installation is expensive or impractical. Such environments
include manufacturing floors, trading floors on stock exchanges, conventions and trade shows, and historic
buildings. With the increasing propagation of wireless LANs comes the need for standardization so as to
allow interoperability for an increasingly mobile workforce. Despite all the advantages and facilities that
Wi-FI offers, there is still the delay problem that is due to many reasons that are introduced in details in
our case study which also presents the solutions and simulation that can reduce this delay for better
performance of the wireless networks
Julien Lavergne, lead developer of lubuntu, gave a presentation about the lubuntu project and ways to involve at the FOSSASIA conference in Ho Chi Minh City (Saigon), Vietnam. Here are the slides.
We the Berlin core team, apply in order to propose Berlin. Our City is the location in Germany to hold DebConf in 2011. We are convinced that Berlin is able to host a very successful and interesting conference. After being held in New York City next year, Berlin for 2011 is a good follow up in Europe. The cities are like antipoles of the old and the new world.
5 Tips for Creating Standard Financial ReportsEasyReports
Well-crafted financial reports serve as vital tools for decision-making and transparency within an organization. By following the undermentioned tips, you can create standardized financial reports that effectively communicate your company's financial health and performance to stakeholders.
Yes of course, you can easily start mining pi network coin today and sell to legit pi vendors in the United States.
Here the telegram contact of my personal vendor.
@Pi_vendor_247
#pi network #pi coins #legit #passive income
#US
Lecture slide titled Fraud Risk Mitigation, Webinar Lecture Delivered at the Society for West African Internal Audit Practitioners (SWAIAP) on Wednesday, November 8, 2023.
Seminar: Gender Board Diversity through Ownership NetworksGRAPE
Seminar on gender diversity spillovers through ownership networks at FAME|GRAPE. Presenting novel research. Studies in economics and management using econometrics methods.
how to swap pi coins to foreign currency withdrawable.DOT TECH
As of my last update, Pi is still in the testing phase and is not tradable on any exchanges.
However, Pi Network has announced plans to launch its Testnet and Mainnet in the future, which may include listing Pi on exchanges.
The current method for selling pi coins involves exchanging them with a pi vendor who purchases pi coins for investment reasons.
If you want to sell your pi coins, reach out to a pi vendor and sell them to anyone looking to sell pi coins from any country around the globe.
Below is the contact information for my personal pi vendor.
Telegram: @Pi_vendor_247
how to sell pi coins in South Korea profitably.DOT TECH
Yes. You can sell your pi network coins in South Korea or any other country, by finding a verified pi merchant
What is a verified pi merchant?
Since pi network is not launched yet on any exchange, the only way you can sell pi coins is by selling to a verified pi merchant, and this is because pi network is not launched yet on any exchange and no pre-sale or ico offerings Is done on pi.
Since there is no pre-sale, the only way exchanges can get pi is by buying from miners. So a pi merchant facilitates these transactions by acting as a bridge for both transactions.
How can i find a pi vendor/merchant?
Well for those who haven't traded with a pi merchant or who don't already have one. I will leave the telegram id of my personal pi merchant who i trade pi with.
Tele gram: @Pi_vendor_247
#pi #sell #nigeria #pinetwork #picoins #sellpi #Nigerian #tradepi #pinetworkcoins #sellmypi
how to sell pi coins effectively (from 50 - 100k pi)DOT TECH
Anywhere in the world, including Africa, America, and Europe, you can sell Pi Network Coins online and receive cash through online payment options.
Pi has not yet been launched on any exchange because we are currently using the confined Mainnet. The planned launch date for Pi is June 28, 2026.
Reselling to investors who want to hold until the mainnet launch in 2026 is currently the sole way to sell.
Consequently, right now. All you need to do is select the right pi network provider.
Who is a pi merchant?
An individual who buys coins from miners on the pi network and resells them to investors hoping to hang onto them until the mainnet is launched is known as a pi merchant.
debuts.
I'll provide you the Telegram username
@Pi_vendor_247
1. Elemental Economics - Introduction to mining.pdfNeal Brewster
After this first you should: Understand the nature of mining; have an awareness of the industry’s boundaries, corporate structure and size; appreciation the complex motivations and objectives of the industries’ various participants; know how mineral reserves are defined and estimated, and how they evolve over time.
The European Unemployment Puzzle: implications from population agingGRAPE
We study the link between the evolving age structure of the working population and unemployment. We build a large new Keynesian OLG model with a realistic age structure, labor market frictions, sticky prices, and aggregate shocks. Once calibrated to the European economy, we quantify the extent to which demographic changes over the last three decades have contributed to the decline of the unemployment rate. Our findings yield important implications for the future evolution of unemployment given the anticipated further aging of the working population in Europe. We also quantify the implications for optimal monetary policy: lowering inflation volatility becomes less costly in terms of GDP and unemployment volatility, which hints that optimal monetary policy may be more hawkish in an aging society. Finally, our results also propose a partial reversal of the European-US unemployment puzzle due to the fact that the share of young workers is expected to remain robust in the US.
Financial Assets: Debit vs Equity Securities.pptxWrito-Finance
financial assets represent claim for future benefit or cash. Financial assets are formed by establishing contracts between participants. These financial assets are used for collection of huge amounts of money for business purposes.
Two major Types: Debt Securities and Equity Securities.
Debt Securities are Also known as fixed-income securities or instruments. The type of assets is formed by establishing contracts between investor and issuer of the asset.
• The first type of Debit securities is BONDS. Bonds are issued by corporations and government (both local and national government).
• The second important type of Debit security is NOTES. Apart from similarities associated with notes and bonds, notes have shorter term maturity.
• The 3rd important type of Debit security is TRESURY BILLS. These securities have short-term ranging from three months, six months, and one year. Issuer of such securities are governments.
• Above discussed debit securities are mostly issued by governments and corporations. CERTIFICATE OF DEPOSITS CDs are issued by Banks and Financial Institutions. Risk factor associated with CDs gets reduced when issued by reputable institutions or Banks.
Following are the risk attached with debt securities: Credit risk, interest rate risk and currency risk
There are no fixed maturity dates in such securities, and asset’s value is determined by company’s performance. There are two major types of equity securities: common stock and preferred stock.
Common Stock: These are simple equity securities and bear no complexities which the preferred stock bears. Holders of such securities or instrument have the voting rights when it comes to select the company’s board of director or the business decisions to be made.
Preferred Stock: Preferred stocks are sometime referred to as hybrid securities, because it contains elements of both debit security and equity security. Preferred stock confers ownership rights to security holder that is why it is equity instrument
<a href="https://www.writofinance.com/equity-securities-features-types-risk/" >Equity securities </a> as a whole is used for capital funding for companies. Companies have multiple expenses to cover. Potential growth of company is required in competitive market. So, these securities are used for capital generation, and then uses it for company’s growth.
Concluding remarks
Both are employed in business. Businesses are often established through debit securities, then what is the need for equity securities. Companies have to cover multiple expenses and expansion of business. They can also use equity instruments for repayment of debits. So, there are multiple uses for securities. As an investor, you need tools for analysis. Investment decisions are made by carefully analyzing the market. For better analysis of the stock market, investors often employ financial analysis of companies.
2. Elemental Economics - Mineral demand.pdfNeal Brewster
After this second you should be able to: Explain the main determinants of demand for any mineral product, and their relative importance; recognise and explain how demand for any product is likely to change with economic activity; recognise and explain the roles of technology and relative prices in influencing demand; be able to explain the differences between the rates of growth of demand for different products.
1. Introduction
Walking down the layers
Into kernelspace
That's it!
Wireless Kernel Tweaking
or how B.A.T.M.A.N. learned to y
Marek Lindner, Simon Wunderlich
December 28, 2007
Marek Lindner, Simon Wunderlich Wireless Kernel Tweaking
2. Introduction
Walking down the layers
Into kernelspace
That's it!
Outline
1 Introduction
what is a (dynamic) routing protocol?
the B.A.T.M.A.N. approach
2 Walking down the layers
layer 3 vs. layer 2
implementation issues
bridging
3 Into kernelspace
what's dierent
interacting with the kernel
4 That's it!
Marek Lindner, Simon Wunderlich Wireless Kernel Tweaking
3. Introduction
Walking down the layers what is a (dynamic) routing protocol?
Into kernelspace the B.A.T.M.A.N. approach
That's it!
Example scenario - 6:00
Marek Lindner, Simon Wunderlich Wireless Kernel Tweaking
4. Introduction
Walking down the layers what is a (dynamic) routing protocol?
Into kernelspace the B.A.T.M.A.N. approach
That's it!
Example scenario - 23:00
Marek Lindner, Simon Wunderlich Wireless Kernel Tweaking
5. Introduction
Walking down the layers what is a (dynamic) routing protocol?
Into kernelspace the B.A.T.M.A.N. approach
That's it!
Example scenario (2)
Marek Lindner, Simon Wunderlich Wireless Kernel Tweaking
6. Introduction
Walking down the layers what is a (dynamic) routing protocol?
Into kernelspace the B.A.T.M.A.N. approach
That's it!
Introduction to B.A.T.M.A.N.
B.A.T.M.A.N. = better approach to mobile adhoc networks
only decide next neighbour, not whole route
topology is not used or known by nodes
routing decisions are distributed by the nodes
designed for lossy networks
routing protocols internal is out of scope, we just assume it
works ;)
Marek Lindner, Simon Wunderlich Wireless Kernel Tweaking
7. Introduction layer 3 vs. layer 2
Walking down the layers implementation issues
Into kernelspace bridging
That's it!
Layer 3 - isn't that enough?
B.A.T.M.A.N. alters routing tables
kernel manages routing of payload trac
this works only for IP, no IPv6, DHCP, IPX ...
users have to make sure that everyone has an unique IP
routing into/outside other networks is quite complex
Marek Lindner, Simon Wunderlich Wireless Kernel Tweaking
8. Introduction layer 3 vs. layer 2
Walking down the layers implementation issues
Into kernelspace bridging
That's it!
Let's try layer 2
write userspace proof-of-concept, then go to kernelspace
instead of IPs, use MAC-addresses as identiers (should
be[TM] unique per design)
we provide a virtual switch-port bat0 to the user
virtual Ethernet interface (TAP), all other nodes are just one
(virtual) hop away
IP, IPv6, DHCP, IPX already works on Ethernet, we have
nothing to do
can be used as bridge over multiple interfaces (e.g. WiFi and
Ethernet)
Marek Lindner, Simon Wunderlich Wireless Kernel Tweaking
9. Introduction layer 3 vs. layer 2
Walking down the layers implementation issues
Into kernelspace bridging
That's it!
Usage
provide a virtual switch-port bat0 to the user
k e r o :/# i f c o n f i g bat0
bat0 L i n k encap : E t h e r n e t HWaddr 0 0 : 1 3 : 3 7 : 9 1 : 4 2 : 3 7
i n e t 6 addr : f e 8 0 : : 2 1 7 : 1 3 f f : f e 3 7 :4237/64 Scope : L i n k
UP BROADCAST RUNNING MULTICAST MTU: 1 4 7 2 M e t r i c : 1
RX p a c k e t s : 0 e r r o r s : 0 dropped : 0 o v e r r u n s : 0 frame : 0
TX p a c k e t s : 4 e r r o r s : 0 dropped : 0 o v e r r u n s : 0 c a r r i e r : 0
c o l l i s i o n s :0 txqueuelen :500
RX b y t e s : 0 ( 0 . 0 B) TX b y t e s : 3 2 8 ( 3 2 8 . 0 B)
participants set IP adresses (etc.) on their bat0 interface
k e r o :/# i f c o n f i g bat0 i n e t 1 9 2 . 1 6 8 . 1 0 . 2 3
k e r o :/# r o u t e add d e f a u l t gw 1 9 2 . 1 6 8 . 1 0 . 2 3
( o r even b e t t e r : )
k e r o :/# d h c l i e n t bat0
Marek Lindner, Simon Wunderlich Wireless Kernel Tweaking
10. Introduction layer 3 vs. layer 2
Walking down the layers implementation issues
Into kernelspace bridging
That's it!
All the layer 2 belong to us!
B.A.T.M.A.N. transports the Ethernet-Frame to the node with
the destination MAC
it does not care about IP-adresses etc, just as your switch
OGMs and payload are encapsulated in our own
Ethernet-Frames (Ethertype 0x0842)
Marek Lindner, Simon Wunderlich Wireless Kernel Tweaking
11. Introduction layer 3 vs. layer 2
Walking down the layers implementation issues
Into kernelspace bridging
That's it!
Implementation
TAP-interface bat0 receives/sends Ethernet-Frames from the
user
we decide which neighbour should receive it, based on the
B.A.T.M.A.N. algorithm
Marek Lindner, Simon Wunderlich Wireless Kernel Tweaking
12. Introduction layer 3 vs. layer 2
Walking down the layers implementation issues
Into kernelspace bridging
That's it!
Bridging support
B.A.T.M.A.N. collects MACs of participants behind the Bridge
These lists are announced via HNA-Messages and ooded to
all B.A.T.M.A.N. nodes
With this, we have a decentralized MAC Translation Table
Marek Lindner, Simon Wunderlich Wireless Kernel Tweaking
13. Introduction layer 3 vs. layer 2
Walking down the layers implementation issues
Into kernelspace bridging
That's it!
Visualization
Nice side eect: with the HNA information, the whole
topology with the nodes behind the APs becomes visible
Marek Lindner, Simon Wunderlich Wireless Kernel Tweaking
14. Introduction layer 3 vs. layer 2
Walking down the layers implementation issues
Into kernelspace bridging
That's it!
Great - and now?
proof-of-concept implementation in the userspace works quite
well
the problem is: performance!
it should also run well on minimal embedded systems (Access
Points, Cell Phones)
typical path is:
select(): wait for a packet
read() it
nd next hop, update tables etc. (pretty fast)
write() it
System Calls for read/write take very long time (switch to
kernel mode and back, copy overhead)
becomes a problem with high bandwidth usage, peak
performance of the NICs can't be reached
Marek Lindner, Simon Wunderlich Wireless Kernel Tweaking
15. Introduction
Walking down the layers what's dierent
Into kernelspace interacting with the kernel
That's it!
Put it into kernelspace
No useless message copy (recycle kernel buers)
no Syscalls and no user/kernel mode switch
kernel works asynchronous and preemptive
asynchronous packet handling possible
Marek Lindner, Simon Wunderlich Wireless Kernel Tweaking
16. Introduction
Walking down the layers what's dierent
Into kernelspace interacting with the kernel
That's it!
Living in the kernelspace
the proc lesystem
# l s / p r o c / n e t /batman−adv /
gateways
interfaces
log
log_level
originators
orig_interval
activating batman-adv
# echo wlan0 / p r o c / n e t /batman−adv / i n t e r f a c e s
deactivating batman-adv
# echo quot;quot; / p r o c / n e t /batman−adv / i n t e r f a c e s
Marek Lindner, Simon Wunderlich Wireless Kernel Tweaking
17. Introduction
Walking down the layers what's dierent
Into kernelspace interacting with the kernel
That's it!
Logging merits special attention
the log level
# c a t / p r o c / n e t /batman−adv / l o g _ l e v e l
[ x ] c r i t i c a l (0)
[ ] warnings (1)
[ ] notices (2)
[ ] batman ( 4 )
[ ] routes (8)
setting the log level
# echo 3 / p r o c / n e t /batman−adv / l o g _ l e v e l
# c a t / p r o c / n e t /batman−adv / l o g _ l e v e l
[ x ] c r i t i c a l (0)
[ x ] warnings (1)
[ x ] notices (2)
[ ] batman ( 4 )
[ ] routes (8)
reading the log
# c a t / p r o c / n e t /batman−adv / l o g
[ 6 2 6 ] B . A .T.M. A .N. Advanced 0.1− a l p h a ( c o m p a b i l i t y v e r s i o n 1)
[ 9 7 1 ] Changing l o g _ l e v e l from : 0 to : 3
Marek Lindner, Simon Wunderlich Wireless Kernel Tweaking
18. Introduction
Walking down the layers what's dierent
Into kernelspace interacting with the kernel
That's it!
Kernel development
don't be scared
the kernel is a big library for all your hacking needs
debugging techniques:
clean programming - think before you insmod
printk - tells you what's up
kernel oops - gives you the stack trace
UML - safer debugging
again: don't panic! :-)
Marek Lindner, Simon Wunderlich Wireless Kernel Tweaking
19. Introduction
Walking down the layers what's dierent
Into kernelspace interacting with the kernel
That's it!
Battool
there is no ICMP on Layer 2
we still want to ping, traceroute etc to debug the network
implement own ICMP protocol into batman-adv protocol
battool provides ping, traceroute and raw packet dump
injects and receives special packets into unix socket
(userspace) or device (kernelspace)
Marek Lindner, Simon Wunderlich Wireless Kernel Tweaking
20. Introduction
Walking down the layers
Into kernelspace
That's it!
Links
http://open-mesh.net/
https://dev.open-mesh.net/batman
Marek Lindner, Simon Wunderlich Wireless Kernel Tweaking
21. Introduction
Walking down the layers
Into kernelspace
That's it!
Thank you!
Marek Lindner, Simon Wunderlich Wireless Kernel Tweaking