It is long known attackers may use forged source IP address to conceal their real locations. To capture the spoofers, a number of IP traceback mechanisms have been proposed. However, due to the challenges of deployment, there has been not a widely adopted IP traceback solution, at least at the Internet level. As a result, the mist on the locations of spoofers has never been dissipated till now.
This paper proposes passive IP traceback (PIT) that bypasses the deployment difficulties of IP traceback techniques. PIT investigates Internet Control Message Protocol error messages (named path backscatter) triggered by spoofing traffic, and tracks the spoofers based on public available information (e.g., topology). In this way, PIT can find the spoofers without any deployment requirement.
This paper illustrates the causes, collection, and the statistical results on path backscatter, demonstrates the processes and effectiveness of PIT, and shows the captured locations of spoofers through applying PIT on the path backscatter data set.
These results
can help further reveal IP spoofing, which has been studied for long but never
well understood. Though PIT cannot work in all the spoofing attacks, it may be
the most useful mechanism to trace spoofers before an Internet-level traceback
system has been deployed in real.
1.2 INTRODUCTION
IP spoofing, which means attackers launching attacks with forged source IP addresses, has been recognized as a serious security problem on the Internet for long. By using addresses that are assigned to others or not assigned at all, attackers can avoid exposing their real locations, or enhance the effect of attacking, or launch reflection based attacks. A number of notorious attacks rely on IP spoofing, including SYN flooding, SMURF, DNS amplification etc. A DNS amplification attack which severely degraded the service of a Top Level Domain (TLD) name server is reported in though there has been a popular conventional wisdom that DoS attacks are launched from botnets and spoofing is no longer critical, the report of ARBOR on NANOG 50th meeting shows spoofing is still significant in observed DoS attacks. Indeed, based on the captured backscatter messages from UCSD Network Telescopes, spoofing activities are still frequently observed.
To capture the origins of IP spoofing traffic is of great importance. As long as the real locations of spoofers are not disclosed, they cannot be deterred from launching further attacks. Even just approaching the spoofers, for example, determining the ASes or networks they reside in, attackers can be located in a smaller area, and filters can be placed closer to the attacker before attacking traffic get aggregated. The last but not the least, identifying the origins of spoofing traffic can help build a reputation system for ASes, which would be helpful to push the corresponding ISPs to verify IP source address.
Instead of proposing another IP traceback mechanism with improved tracking capability, we propose a novel solution, named Passive IP Traceback (PIT), to bypass the challenges in deployment. Routers may fail to forward an IP spoofing packet due to various reasons, e.g., TTL exceeding. In such cases, the routers may generate an ICMP error message (named path backscatter) and send the message to the spoofed source address. Because the routers can be close to the spoofers, the path backscatter messages may potentially disclose the locations of the spoofers. PIT exploits these path backscatter messages to find the location of the spoofers. With the locations of the spoofers known, the victim can seek help from the corresponding ISP to filter out the attacking packets, or take other counterattacks. PIT is especially useful for the victims in reflection based spoofing attacks, e.g., DNS amplification attacks. The victims can find the locations of the spoofers directly from the attacking traffic.
In this article, at first we illustrate the generation, types, collection, and the security issues of path backscatter messages in section III. Then in section IV, we present PIT, which tracks the location of the spoofers based on path backscatter messages together with the topology and routing information. We discuss how to apply PIT when both topology and routing are known, or only topology is known, or neither are known respectively. We also present two effective algorithms to apply PIT in large scale networks. In the following section, at first we show the statistical results on path backscatter messages. Then we evaluate the two key mechanisms of PIT which work without routing information. At last, we give the tracking result when applying PIT on the path backscatter message dataset: a number of ASes in which spoofers are found.
Our work has the following contributions:
1) This is the first article known which
deeply investigates path backscatter messages. These messages are valuable to
help understand spoofing activities. Though Moore et al. [8] has exploited
backscatter messages, which are generated by the targets of spoofing messages, to
study Denial of Services (DoS), path backscatter messages, which are sent by
intermediate devices rather than the targets, have not been used in traceback. 2)
A practical and effective IP traceback solution based on path backscatter
messages, i.e., PIT, is proposed. PIT bypasses the deployment difficulties of
existing IP traceback mechanisms and actually is already in force. Though given
the limitation that path backscatter messages are not generated with stable
possibility, PIT cannot work in all the attacks, but it does work in a number
of spoofing activities. At least it may be the most useful traceback mechanism
before an AS-level traceback system has been deployed in real. 3) Through
applying PIT on the path backscatter dataset, a number of locations of spoofers
are captured and presented. Though this is not a complete list, it is the first
known list disclosing the locations of spoofers.
1.3 LITRATURE SURVEY
DEFENSE AGAINST SPOOFED IP TRAFFIC USING HOP-COUNT FILTERING
PUBLICATION: IEEE/ACM Trans. Netw., vol. 15, no. 1, pp. 40–53, Feb. 2007.
AUTHORS: H. Wang, C. Jin, and K. G. Shin
EXPLANATION:
IP spoofing has often
been exploited by Distributed Denial of Service (DDoS) attacks to: 1)conceal
flooding sources and dilute localities in flooding traffic, and 2)coax
legitimate hosts into becoming reflectors, redirecting and amplifying flooding
traffic. Thus, the ability to filter spoofed IP packets near victim servers is
essential to their own protection and prevention of becoming involuntary DoS
reflectors. Although an attacker can forge any field in the IP header, he
cannot falsify the number of hops an IP packet takes to reach its destination.
More importantly, since the hop-count values are diverse, an attacker cannot
randomly spoof IP addresses while maintaining consistent hop-counts. On the
other hand, an Internet server can easily infer the hop-count information from
the Time-to-Live (TTL) field of the IP header. Using a mapping between IP
addresses and their hop-counts, the server can distinguish spoofed IP packets
from legitimate ones. Based on this observation, we present a novel filtering
technique, called Hop-Count Filtering (HCF)-which builds an accurate
IP-to-hop-count (IP2HC) mapping table-to detect and discard spoofed IP packets.
HCF is easy to deploy, as it does not require any support from the underlying
network. Through analysis using network measurement data, we show that HCF can
identify close to 90% of spoofed IP packets, and then discard them with little
collateral damage. We implement and evaluate HCF in the Linux kernel,
demonstrating its effectiveness with experimental measurements
DYNAMIC PROBABILISTIC PACKET MARKING FOR EFFICIENT IP TRACEBACK
PUBLICATION: Comput. Netw., vol. 51, no. 3, pp. 866–882, 2007.
AUTHORS: J. Liu, Z.-J. Lee, and Y.-C. Chung
EXPLANATION:
Recently, denial-of-service
(DoS) attack has become a pressing problem due to the lack of an efficient
method to locate the real attackers and ease of launching an attack with
readily available source codes on the Internet. Traceback is a subtle scheme to
tackle DoS attacks. Probabilistic packet marking (PPM) is a new way for
practical IP traceback. Although PPM enables a victim to pinpoint the
attacker’s origin to within 2–5 equally possible sites, it has been shown that
PPM suffers from uncertainty under spoofed marking attack. Furthermore, the
uncertainty factor can be amplified significantly under distributed DoS attack,
which may diminish the effectiveness of PPM. In this work, we present a new
approach, called dynamic probabilistic packet marking (DPPM), to further
improve the effectiveness of PPM. Instead of using a fixed marking probability,
we propose to deduce the traveling distance of a packet and then choose a
proper marking probability. DPPM may completely remove uncertainty and enable
victims to precisely pinpoint the attacking origin even under spoofed marking
DoS attacks. DPPM supports incremental deployment. Formal analysis indicates
that DPPM outperforms PPM in most aspects.
FLEXIBLE DETERMINISTIC PACKET MARKING: AN IP TRACEBACK SYSTEM TO FIND THE REAL SOURCE OF ATTACKS
PUBLICATION: EEE Trans. Parallel Distrib. Syst., vol. 20, no. 4, pp. 567–580, Apr. 2009.
AUTHORS: Y. Xiang, W. Zhou, and M. Guo
EXPLANATION:
IP traceback is the
enabling technology to control Internet crime. In this paper we present a novel
and practical IP traceback system called Flexible Deterministic Packet Marking
(FDPM) which provides a defense system with the ability to find out the real
sources of attacking packets that traverse through the network. While a number
of other traceback schemes exist, FDPM provides innovative features to trace
the source of IP packets and can obtain better tracing capability than others.
In particular, FDPM adopts a flexible mark length strategy to make it
compatible to different network environments; it also adaptively changes its
marking rate according to the load of the participating router by a flexible
flow-based marking scheme. Evaluations on both simulation and real system
implementation demonstrate that FDPM requires a moderately small number of
packets to complete the traceback process; add little additional load to
routers and can trace a large number of sources in one traceback process with
low false positive rates. The built-in overload prevention mechanism makes this
system capable of achieving a satisfactory traceback result even when the
router is heavily loaded. It has been used to not only trace DDoS attacking
packets but also enhance filtering attacking traffic.
CHAPTER 2
2.0 SYSTEM ANALYSIS
2.1 EXISTING SYSTEM:
Existing methods of the IP marking approach is that routers probabilistically write some encoding of partial path information into the packets during forwarding. A basic technique, the edge sampling algorithm, is to write edge information into the packets. This scheme reserves two static fields of the size of IP address, start and end, and a static distance field in each packet. Each router updates these fields as follows. Each router marks the packet with a probability. When the router decides to mark the packet, it writes its own IP address into the start field and writes zero into the distance field. Otherwise, if the distance field is already zero which indicates its previous router marked the packet, it writes its own IP address into the end field, thus represents the edge between itself and the previous routers.
Previous router doesn’t mark the packet,
then it always increments the distance field. Thus the distance field in the
packet indicates the number of routers the packet has traversed from the router
which marked the packet to the victim. The distance field should be updated
using a saturating addition, meaning that the distance field is not allowed to
wrap. The mandatory increment of the distance field is used to avoid spoofing
by an attacker. Using such a scheme, any packet written by the attacker will
have distance field greater than or equal to the length of the real attack path
a router false positive if it is in the reconstructed attack graph but not in
the real attack graph. Similarly we call a router false negative if it is in
the true attack graph but not in the reconstructed attack graph. We call a
solution to the IP traceback problem robust if it has very low rate of false
negatives and false positives.
2.1.1 DISADVANTAGES:
- Existing approach has a very high computation overhead for the victim to reconstruct the attack paths, and gives a large number of false positives when the denial-of-service attack originates from multiple attackers.
- Existing approach can require days of computation to reconstruct the attack paths and give thousands of false positives even when there are only 25 distributed attackers. This approach is also vulnerable to compromised routers.
- If a router is compromised, it can forge markings from other uncompromised routers and hence lead the reconstruction to wrong results. Even worse, the victim will not be able to tell a router is compromised just from the information in the packets it receives problem.
2.2 PROPOSED SYSTEM:
We propose a novel solution, named Passive IP Traceback (PIT), to bypass the challenges in deployment. Routers may fail to forward an IP spoofing packet due to various reasons, e.g., TTL exceeding. In such cases, the routers may generate an ICMP error message (named path backscatter) and send the message to the spoofed source address. Because the routers can be close to the spoofers, the path backscatter messages may potentially disclose the locations of the spoofers. PIT exploits these path backscatter messages to find the location of the spoofers. With the locations of the spoofers known, the victim can seek help from the corresponding ISP to filter out the attacking packets, or take other counterattacks. PIT is especially useful for the victims in reflection based spoofing attacks, e.g., DNS amplification attacks. The victims can find the locations of the spoofers directly from the attacking traffic.
We present PIT, which tracks the
location of the spoofers based on path backscatter messages together with the
topology and routing information. We discuss how to apply PIT when both
topology and routing are known, or only topology is known, or neither are known
respectively. We also present two effective algorithms to apply PIT in large
scale networks. In the following section, at first we show the statistical
results on path backscatter messages. Then we evaluate the two key mechanisms
of PIT which work without routing information. At last, we give the tracking
result when applying PIT on the path backscatter message dataset: a number of
ASes in which spoofers are found.
2.2.1 ADVANTAGES:
1) This is the first article known which deeply investigates path backscatter messages. These messages are valuable to help understand spoofing activities has exploited backscatter messages, which are generated by the targets of spoofing messages, to study Denial of Services (DoS), path backscatter messages, which are sent by intermediate devices rather than the targets, have not been used in traceback.
2) A practical and effective IP traceback solution based on path backscatter messages, i.e., PIT, is proposed. PIT bypasses the deployment difficulties of existing IP traceback mechanisms and actually is already in force. Though given the limitation that path backscatter messages are not generated with stable possibility, PIT cannot work in all the attacks, but it does work in a number of spoofing activities. At least it may be the most useful traceback mechanism before an AS-level traceback system has been deployed in real.
3) Through applying PIT on the path backscatter
dataset, a number of locations of spoofers are captured and presented. Though
this is not a complete list, it is the first known list disclosing the
locations of spoofers.
2.3 HARDWARE & SOFTWARE REQUIREMENTS:
2.3.1 HARDWARE REQUIREMENT:
v Processor – Pentium –IV
- Speed –
1.1 GHz
- RAM – 256 MB (min)
- Hard Disk – 20 GB
- Floppy Drive – 1.44 MB
- Key Board – Standard Windows Keyboard
- Mouse – Two or Three Button Mouse
- Monitor – SVGA
2.3.2 SOFTWARE REQUIREMENTS:
- Operating System : Windows XP or Win7
- Front End : JAVA JDK 1.7
- Document : MS-Office 2007
CHAPTER 3
3.0 SYSTEM DESIGN:
Data Flow Diagram / Use Case Diagram / Flow Diagram:
- The DFD is also called as bubble chart. It is a simple graphical formalism that can be used to represent a system in terms of the input data to the system, various processing carried out on these data, and the output data is generated by the system
- The data flow diagram (DFD) is one of the most important modeling tools. It is used to model the system components. These components are the system process, the data used by the process, an external entity that interacts with the system and the information flows in the system.
- DFD shows how the information moves through the system and how it is modified by a series of transformations. It is a graphical technique that depicts information flow and the transformations that are applied as data moves from input to output.
- DFD is also known as bubble chart. A DFD may be used to represent a system at any level of abstraction. DFD may be partitioned into levels that represent increasing information flow and functional detail.
NOTATION:
SOURCE OR DESTINATION OF DATA:
External sources or destinations, which may be people or organizations or other entities
DATA SOURCE:
Here the data referenced by a process is stored and retrieved.
PROCESS:
People, procedures or devices that produce data’s in the physical component is not identified.
DATA FLOW:
Data moves in a specific direction from an origin to
a destination. The data flow is a “packet” of data.
There are several common modeling rules when creating DFDs:
- All processes must have at least one data flow in and one data flow out.
- All processes should modify the incoming data, producing new forms of outgoing data.
- Each data store must be involved with at least one data flow.
- Each external entity must be involved with at least one data flow.
- A data flow must be attached to at least one process.
3.1 ARCHITECTURE DIAGRAM
3.2 DATAFLOW DIAGRAM:
LEVEL 1
| Base station |
| View request |
| Router check the node |
| Message send via router |
LEVEL 2
| Node |
| Exists |
| Send request |
| Receive message |
| Check IP Address & check verification node |
| Clear Spoofing Attacks |
LEVEL 3
| Router |
| IP Address |
| Router check the each node |
| Check verification same/diff node to each data |
| Response to node |
| Detect Spoofing Origin and send message to original node |
3.2.1 UML DIAGRAMS:
3.2.2 USE CASE DIAGRAM:
| Base station |
| Router |
| Create message |
| View request |
| Message send via router |
| Router check each node |
| Check verification same/diff node to each data |
| Response to client |
| Detect spoofing origin |
| Send message |
| Node |
| Send request |
3.2.3 CLASS DIAGRAM:
| Node |
| IP Adress |
| Send request |
| View message () |
| Base station |
| IP Address |
| View request |
| Send message via router |
| Socket connection () () |
| Send message () () |
| Router |
| IP Address |
| Router check the each node |
| Detectsppofing() () |
| Receive message () |
| Response to nde |
| Send message() () |
3.2.4 SEQUENCE DIAGRAM:
| Connection established |
| Send encoded data |
| Check verification |
| Form routing |
| Routing Finished |
| Detect Spoofing |
| Connection terminate |
| Source |
| Base station |
| Destination |
| Establish communication |
| Connection established |
| Receiving Ack |
| Data received |
| Routing Success |
3.2. ACTIVITY DIAGRAM:
| Node |
| Router |
| Check |
| Check verification same/diff node to each data |
| Router check the each node |
| Clear jamming and send message to node |
| Response to client |
| Yes Start msg receive |
| No |
| IP Address & View request |
| IP Address |
| Send request |
| Message Received |
| Base station |
| Message send via router |
| Router check the node |
CHAPTER 4
4.0 IMPLEMENTATION:
4.1 ALGORITHM
We designed an algorithm specified in
Fig. 6. This algorithm first finds a shortest path from r to od.
From the second vertex along the path, it checks if the removal of the vertex
can break r and od. Whenever such a vertex c is found,
removing the vertex from G, and the set containing all the verticals
which are still connected with r is just the suspect set.
4.2 MODULES:
NETWORK SECURITY:
DENIAL OF SERVICE (DOS):
PATH BACKSCATTER:
IP SPOOFING METHOD:
IP
TRACEBACK METHOD:
4.3 MODULE DESCRIPTION:
NETWORK SECURITY:
Network-accessible resources may be deployed in a network as surveillance and early-warning tools, as the detection of attackers are not normally accessed for legitimate purposes. Techniques used by the attackers that attempt to compromise these decoy resources are studied during and after an attack to keep an eye on new exploitation techniques. Such analysis may be used to further tighten security of the actual network being protected by the data’s. Data forwarding can also direct an attacker’s attention away from legitimate servers. A user encourages attackers to spend their time and energy on the decoy server while distracting their attention from the data on the real server. Similar to a server, a user is a network set up with intentional vulnerabilities. Its purpose is also to invite attacks so that the attacker’s methods can be studied and that information can be used to increase network security.
DENIAL OF SERVICE (DOS):
In computing, a denial-of-service (DoS) attack is an attempt to make a machine or network resource unavailable to its intended users, such as to temporarily or indefinitely interrupt or suspend services of a host connected to the Internet. A distributed denial-of-service (DDoS) is where the attack source is more than one, often thousands of, unique IP addresses. It is analogous to a group of people crowding the entry door or gate to a shop or business, and not letting legitimate parties enter into the shop or business, disrupting normal operations.
Criminal perpetrators of DoS attacks often target sites or services hosted on high-profile web servers such as banks, credit card payment gateways; but motives of revenge, blackmail or activism can be behind other attacks. A denial-of-service attack is characterized by an explicit attempt by attackers to prevent legitimate users of a service from using that service. There are two general forms of DoS attacks: those that crash services and those that flood services.
The most serious attacks are distributed and in many or most cases involve forging of IP sender addresses (IP address spoofing) so that the location of the attacking machines cannot easily be identified, nor can filtering be done based on the source address.
PATH BACKSCATTER:
We presented a preliminary statistical
result on path backscatter messages and discussed it is possible to trace
spoofers based on the messages. However, the generation and collection of path
backscatter messages are not well investigated, and the traceback mechanisms
are not designed. In this article, we make a thorough analysis on path
backscatter messages, present the traceback mechanisms and give the traceback
results. 2. Each message contains the source address of the reflecting device,
and the IP header of the original packet. Thus, from each path backscatter, we
can get 1) the IP address of the reflecting device which is on the path from
the attacker to the destination of the spoofing packet; 2) the IP address of
the original destination of the spoofing packet. The original IP header also
contains other valuable information, e.g., the remaining TTL of the spoofing
packet. Note that due to some network devices may perform address rewrite
(e.g., NAT), the original source address and the destination address may be
different.
IP SPOOFING METHOD:
Our tracking mechanisms actually have two limitations. The first is the network topology and mapping from addresses of r and od must be known. The second is the tracking is actually performed based on loose assumptions on paths. Thus, only when path backscatter messages are from very special vertex, i.e., stub AS, the spoofer can be accurately located. In this section, we discuss how to break these limitations through using other information contained in path backscatter messages.
We found there are three special types of path backscatter messages which are more useful for tracing spoofers:
1) The path backscatter messages whose original hop count is 0 or 1. Such messages are generated 1 or 2 hops from the spoofers. Very possibly they are from the gateway of the spoofer.
2) The path backscatter messages whose type is ‘Redirect’. Such messages must be from a gateway of the spoofer.
3) The path backscatter messages whose
original destination is a private address or unallocated address. Such messages
are typically generated by the first DFZ router on the path from the spoofer to
the original destination, e.g., the egress router of the AS in which the
spoofer resides. Though such path backscatter messages are generated in very
special cases, they are not rare. Especially, there are a large number of path
backscatter messages whose original destination is a private address.
IP TRACEBACK METHOD:
PIT is very different from any existing traceback mechanism. The main difference is the generation of path backscatter message is not of a certain probability. Thus, we separate the evaluation into 3 parts: the first is the statistical results on path backscatter messages; the second is the evaluation on the traceback mechanisms presented in considering uncertainness of path backscatter generation, since effectiveness of the mechanisms is actually determined by the structure features of the networks; the last is the result of performing the traceback mechanisms on the path backscatter message dataset.
In this article, we proposed Passive IP Traceback (PIT) which tracks spoofers based on path backscatter messages and public available information. We illustrate causes, collection, and statistical results on path backscatter. We specified how to apply PIT when the topology and routing are both known, or the routing is unknown, or neither of them are known. We presented two effective algorithms to apply PIT in large scale networks and proofed their correctness. We demonstrated the effectiveness of PIT based on deduction and simulation. We showed the captured locations of spoofers through applying PIT on the path backscatter dataset. These results can help further reveal IP spoofing, which has been studied for long but never well understood.
CHAPTER 5
5.0 SYSTEM STUDY:
5.1 FEASIBILITY STUDY:
The feasibility of the project is analyzed in this phase and business proposal is put forth with a very general plan for the project and some cost estimates. During system analysis the feasibility study of the proposed system is to be carried out. This is to ensure that the proposed system is not a burden to the company. For feasibility analysis, some understanding of the major requirements for the system is essential.
Three key considerations involved in the feasibility analysis are
- ECONOMICAL FEASIBILITY
- TECHNICAL FEASIBILITY
- SOCIAL FEASIBILITY
5.1.1 ECONOMICAL FEASIBILITY:
This study is carried out to check the economic impact that the system will have on the organization. The amount of fund that the company can pour into the research and development of the system is limited. The expenditures must be justified. Thus the developed system as well within the budget and this was achieved because most of the technologies used are freely available. Only the customized products had to be purchased.
5.1.2 TECHNICAL FEASIBILITY
This study is carried out to check the technical feasibility, that is, the technical requirements of the system. Any system developed must not have a high demand on the available technical resources. This will lead to high demands on the available technical resources. This will lead to high demands being placed on the client. The developed system must have a modest requirement, as only minimal or null changes are required for implementing this system.
5.1.3 SOCIAL FEASIBILITY:
The aspect of study is to check the level of acceptance of the system by the user. This includes the process of training the user to use the system efficiently. The user must not feel threatened by the system, instead must accept it as a necessity. The level of acceptance by the users solely depends on the methods that are employed to educate the user about the system and to make him familiar with it. His level of confidence must be raised so that he is also able to make some constructive criticism, which is welcomed, as he is the final user of the system.
5.2 SYSTEM TESTING:
Testing is a process of checking whether the developed system is working according to the original objectives and requirements. It is a set of activities that can be planned in advance and conducted systematically. Testing is vital to the success of the system. System testing makes a logical assumption that if all the parts of the system are correct, the global will be successfully achieved. In adequate testing if not testing leads to errors that may not appear even many months.
This creates two problems, the time lag between the cause and the appearance of the problem and the effect of the system errors on the files and records within the system. A small system error can conceivably explode into a much larger Problem. Effective testing early in the purpose translates directly into long term cost savings from a reduced number of errors. Another reason for system testing is its utility, as a user-oriented vehicle before implementation. The best programs are worthless if it produces the correct outputs.
5.2.1 UNIT TESTING:
| Description | Expected result |
| Test for application window properties. | All the properties of the windows are to be properly aligned and displayed. |
| Test for mouse operations. | All the mouse operations like click, drag, etc. must perform the necessary operations without any exceptions. |
A program represents the
logical elements of a system. For a program to run satisfactorily, it must
compile and test data correctly and tie in properly with other programs.
Achieving an error free program is the responsibility of the programmer.
Program testing checks
for two types
of errors: syntax
and logical. Syntax error is a
program statement that violates one or more rules of the language in which it
is written. An improperly defined field dimension or omitted keywords are
common syntax errors. These errors are shown through error message generated by
the computer. For Logic errors the programmer must examine the output
carefully.
5.1.2 FUNCTIONAL TESTING:
Functional testing of an application is used to prove the application delivers correct results, using enough inputs to give an adequate level of confidence that will work correctly for all sets of inputs. The functional testing will need to prove that the application works for each client type and that personalization function work correctly.When a program is tested, the actual output is compared with the expected output. When there is a discrepancy the sequence of instructions must be traced to determine the problem. The process is facilitated by breaking the program into self-contained portions, each of which can be checked at certain key points. The idea is to compare program values against desk-calculated values to isolate the problems.
| Description | Expected result |
| Test for all modules. | All peers should communicate in the group. |
| Test for various peer in a distributed network framework as it display all users available in the group. | The result after execution should give the accurate result. |
5.1. 3 NON-FUNCTIONAL TESTING:
The Non Functional software testing encompasses a rich spectrum of testing strategies, describing the expected results for every test case. It uses symbolic analysis techniques. This testing used to check that an application will work in the operational environment. Non-functional testing includes:
- Load testing
- Performance testing
- Usability testing
- Reliability testing
- Security testing
5.1.4 LOAD TESTING:
An important tool for implementing system tests is a Load generator. A Load generator is essential for testing quality requirements such as performance and stress. A load can be a real load, that is, the system can be put under test to real usage by having actual telephone users connected to it. They will generate test input data for system test.
| Description | Expected result |
| It is necessary to ascertain that the application behaves correctly under loads when ‘Server busy’ response is received. | Should designate another active node as a Server. |
5.1.5 PERFORMANCE TESTING:
Performance tests are utilized in order to determine the widely defined performance of the software system such as execution time associated with various parts of the code, response time and device utilization. The intent of this testing is to identify weak points of the software system and quantify its shortcomings.
| Description | Expected result |
| This is required to assure that an application perforce adequately, having the capability to handle many peers, delivering its results in expected time and using an acceptable level of resource and it is an aspect of operational management. | Should handle large input values, and produce accurate result in a expected time. |
5.1.6 RELIABILITY TESTING:
The software reliability is the ability of a system or component to perform its required functions under stated conditions for a specified period of time and it is being ensured in this testing. Reliability can be expressed as the ability of the software to reveal defects under testing conditions, according to the specified requirements. It the portability that a software system will operate without failure under given conditions for a given time interval and it focuses on the behavior of the software element. It forms a part of the software quality control team.
| Description | Expected result |
| This is to check that the server is rugged and reliable and can handle the failure of any of the components involved in provide the application. | In case of failure of the server an alternate server should take over the job. |
5.1.7 SECURITY TESTING:
Security testing evaluates system characteristics that relate to the availability, integrity and confidentiality of the system data and services. Users/Clients should be encouraged to make sure their security needs are very clearly known at requirements time, so that the security issues can be addressed by the designers and testers.
| Description | Expected result |
| Checking that the user identification is authenticated. | In case failure it should not be connected in the framework. |
| Check whether group keys in a tree are shared by all peers. | The peers should know group key in the same group. |
5.1.8 WHITE BOX TESTING:
White box testing, sometimes called glass-box testing is a test case design method that uses the control structure of the procedural design to derive test cases. Using white box testing method, the software engineer can derive test cases. The White box testing focuses on the inner structure of the software structure to be tested.
| Description | Expected result |
| Exercise all logical decisions on their true and false sides. | All the logical decisions must be valid. |
| Execute all loops at their boundaries and within their operational bounds. | All the loops must be finite. |
| Exercise internal data structures to ensure their validity. | All the data structures must be valid. |
5.1.9 BLACK BOX TESTING:
Black box testing, also called behavioral testing, focuses on the functional requirements of the software. That is, black testing enables the software engineer to derive sets of input conditions that will fully exercise all functional requirements for a program. Black box testing is not alternative to white box techniques. Rather it is a complementary approach that is likely to uncover a different class of errors than white box methods. Black box testing attempts to find errors which focuses on inputs, outputs, and principle function of a software module. The starting point of the black box testing is either a specification or code. The contents of the box are hidden and the stimulated software should produce the desired results.
| Description | Expected result |
| To check for incorrect or missing functions. | All the functions must be valid. |
| To check for interface errors. | The entire interface must function normally. |
| To check for errors in a data structures or external data base access. | The database updation and retrieval must be done. |
| To check for initialization and termination errors. | All the functions and data structures must be initialized properly and terminated normally. |
All
the above system testing strategies are carried out in as the development,
documentation and institutionalization of the proposed goals and related
policies is essential.
CHAPTER 6
6.0 SOFTWARE DESCRIPTION:
6.1 JAVA TECHNOLOGY:
Java technology is both a programming language and a platform.
The Java Programming Language
The Java programming language is a high-level language that can be characterized by all of the following buzzwords:
- Simple
- Architecture neutral
- Object oriented
- Portable
- Distributed
- High performance
- Interpreted
- Multithreaded
- Robust
- Dynamic
- Secure
With most programming languages, you either compile or interpret a program so that you can run it on your computer. The Java programming language is unusual in that a program is both compiled and interpreted. With the compiler, first you translate a program into an intermediate language called Java byte codes —the platform-independent codes interpreted by the interpreter on the Java platform. The interpreter parses and runs each Java byte code instruction on the computer. Compilation happens just once; interpretation occurs each time the program is executed. The following figure illustrates how this works.
You can think of Java byte codes as the machine code instructions for the Java Virtual Machine (Java VM). Every Java interpreter, whether it’s a development tool or a Web browser that can run applets, is an implementation of the Java VM. Java byte codes help make “write once, run anywhere” possible. You can compile your program into byte codes on any platform that has a Java compiler. The byte codes can then be run on any implementation of the Java VM. That means that as long as a computer has a Java VM, the same program written in the Java programming language can run on Windows 2000, a Solaris workstation, or on an iMac.
6.2 THE JAVA PLATFORM:
A platform is the hardware or software environment in which a program runs. We’ve already mentioned some of the most popular platforms like Windows 2000, Linux, Solaris, and MacOS. Most platforms can be described as a combination of the operating system and hardware. The Java platform differs from most other platforms in that it’s a software-only platform that runs on top of other hardware-based platforms.
The Java platform has two components:
- The Java Virtual Machine (Java VM)
- The Java Application Programming Interface (Java API)
You’ve already been introduced to the Java VM. It’s the base for the Java platform and is ported onto various hardware-based platforms.
The Java API is a large collection of ready-made software components that provide many useful capabilities, such as graphical user interface (GUI) widgets. The Java API is grouped into libraries of related classes and interfaces; these libraries are known as packages. The next section, What Can Java Technology Do? Highlights what functionality some of the packages in the Java API provide.
The following figure depicts a program that’s running on the Java platform. As the figure shows, the Java API and the virtual machine insulate the program from the hardware.
Native code is code that after you compile it, the compiled code runs on a specific hardware platform. As a platform-independent environment, the Java platform can be a bit slower than native code. However, smart compilers, well-tuned interpreters, and just-in-time byte code compilers can bring performance close to that of native code without threatening portability.
6.3 WHAT CAN JAVA TECHNOLOGY DO?
The most common types of programs written in the Java programming language are applets and applications. If you’ve surfed the Web, you’re probably already familiar with applets. An applet is a program that adheres to certain conventions that allow it to run within a Java-enabled browser.
However, the Java programming language is not just for writing cute, entertaining applets for the Web. The general-purpose, high-level Java programming language is also a powerful software platform. Using the generous API, you can write many types of programs.
An application is a standalone program that runs directly on the Java platform. A special kind of application known as a server serves and supports clients on a network. Examples of servers are Web servers, proxy servers, mail servers, and print servers. Another specialized program is a servlet.
A servlet can almost be thought of as an applet that runs on the server side. Java Servlets are a popular choice for building interactive web applications, replacing the use of CGI scripts. Servlets are similar to applets in that they are runtime extensions of applications. Instead of working in browsers, though, servlets run within Java Web servers, configuring or tailoring the server.
How does the API support all these kinds of programs? It does so with packages of software components that provides a wide range of functionality. Every full implementation of the Java platform gives you the following features:
- The essentials: Objects, strings, threads, numbers, input and output, data structures, system properties, date and time, and so on.
- Applets: The set of conventions used by applets.
- Networking: URLs, TCP (Transmission Control Protocol), UDP (User Data gram Protocol) sockets, and IP (Internet Protocol) addresses.
- Internationalization: Help for writing programs that can be localized for users worldwide. Programs can automatically adapt to specific locales and be displayed in the appropriate language.
- Security: Both low level and high level, including electronic signatures, public and private key management, access control, and certificates.
- Software components: Known as JavaBeansTM, can plug into existing component architectures.
- Object serialization: Allows lightweight persistence and communication via Remote Method Invocation (RMI).
- Java Database Connectivity (JDBCTM): Provides uniform access to a wide range of relational databases.
The Java platform also has APIs for 2D and 3D graphics, accessibility, servers, collaboration, telephony, speech, animation, and more. The following figure depicts what is included in the Java 2 SDK.
6.4 HOW WILL JAVA TECHNOLOGY CHANGE MY LIFE?
We can’t promise you fame, fortune, or even a job if you learn the Java programming language. Still, it is likely to make your programs better and requires less effort than other languages. We believe that Java technology will help you do the following:
- Get started quickly: Although the Java programming language is a powerful object-oriented language, it’s easy to learn, especially for programmers already familiar with C or C++.
- Write less code: Comparisons of program metrics (class counts, method counts, and so on) suggest that a program written in the Java programming language can be four times smaller than the same program in C++.
- Write better code: The Java programming language encourages good coding practices, and its garbage collection helps you avoid memory leaks. Its object orientation, its JavaBeans component architecture, and its wide-ranging, easily extendible API let you reuse other people’s tested code and introduce fewer bugs.
- Develop programs more quickly: Your development time may be as much as twice as fast versus writing the same program in C++. Why? You write fewer lines of code and it is a simpler programming language than C++.
- Avoid platform dependencies with 100% Pure Java: You can keep your program portable by avoiding the use of libraries written in other languages. The 100% Pure JavaTM Product Certification Program has a repository of historical process manuals, white papers, brochures, and similar materials online.
- Write once, run anywhere: Because 100% Pure Java programs are compiled into machine-independent byte codes, they run consistently on any Java platform.
- Distribute software more easily: You can upgrade applets easily from a central server. Applets take advantage of the feature of allowing new classes to be loaded “on the fly,” without recompiling the entire program.
6.5 ODBC:
Microsoft Open Database Connectivity (ODBC) is a standard programming interface for application developers and database systems providers. Before ODBC became a de facto standard for Windows programs to interface with database systems, programmers had to use proprietary languages for each database they wanted to connect to. Now, ODBC has made the choice of the database system almost irrelevant from a coding perspective, which is as it should be. Application developers have much more important things to worry about than the syntax that is needed to port their program from one database to another when business needs suddenly change.
Through the ODBC Administrator in Control Panel, you can specify the particular database that is associated with a data source that an ODBC application program is written to use. Think of an ODBC data source as a door with a name on it. Each door will lead you to a particular database. For example, the data source named Sales Figures might be a SQL Server database, whereas the Accounts Payable data source could refer to an Access database. The physical database referred to by a data source can reside anywhere on the LAN.
The ODBC system files are not installed on your system by Windows 95. Rather, they are installed when you setup a separate database application, such as SQL Server Client or Visual Basic 4.0. When the ODBC icon is installed in Control Panel, it uses a file called ODBCINST.DLL. It is also possible to administer your ODBC data sources through a stand-alone program called ODBCADM.EXE. There is a 16-bit and a 32-bit version of this program and each maintains a separate list of ODBC data sources.
From a programming perspective, the beauty of ODBC is that the application can be written to use the same set of function calls to interface with any data source, regardless of the database vendor. The source code of the application doesn’t change whether it talks to Oracle or SQL Server. We only mention these two as an example. There are ODBC drivers available for several dozen popular database systems. Even Excel spreadsheets and plain text files can be turned into data sources. The operating system uses the Registry information written by ODBC Administrator to determine which low-level ODBC drivers are needed to talk to the data source (such as the interface to Oracle or SQL Server). The loading of the ODBC drivers is transparent to the ODBC application program. In a client/server environment, the ODBC API even handles many of the network issues for the application programmer.
The advantages
of this scheme are so numerous that you are probably thinking there must be
some catch. The only disadvantage of ODBC is that it isn’t as efficient as
talking directly to the native database interface. ODBC has had many detractors
make the charge that it is too slow. Microsoft has always claimed that the
critical factor in performance is the quality of the driver software that is
used. In our humble opinion, this is true. The availability of good ODBC
drivers has improved a great deal recently. And anyway, the criticism about
performance is somewhat analogous to those who said that compilers would never
match the speed of pure assembly language. Maybe not, but the compiler (or
ODBC) gives you the opportunity to write cleaner programs, which means you
finish sooner. Meanwhile, computers get faster every year.
6.6 JDBC:
In an effort to set an independent database standard API for Java; Sun Microsystems developed Java Database Connectivity, or JDBC. JDBC offers a generic SQL database access mechanism that provides a consistent interface to a variety of RDBMSs. This consistent interface is achieved through the use of “plug-in” database connectivity modules, or drivers. If a database vendor wishes to have JDBC support, he or she must provide the driver for each platform that the database and Java run on.
To gain a wider acceptance of JDBC, Sun based JDBC’s framework on ODBC. As you discovered earlier in this chapter, ODBC has widespread support on a variety of platforms. Basing JDBC on ODBC will allow vendors to bring JDBC drivers to market much faster than developing a completely new connectivity solution.
JDBC was announced in March of 1996. It was released for a 90 day public review that ended June 8, 1996. Because of user input, the final JDBC v1.0 specification was released soon after.
The remainder of this section will cover enough information about JDBC for you to know what it is about and how to use it effectively. This is by no means a complete overview of JDBC. That would fill an entire book.
6.7 JDBC Goals:
Few software packages are designed without goals in mind. JDBC is one that, because of its many goals, drove the development of the API. These goals, in conjunction with early reviewer feedback, have finalized the JDBC class library into a solid framework for building database applications in Java.
The goals that were set for JDBC are important. They will give you some insight as to why certain classes and functionalities behave the way they do. The eight design goals for JDBC are as follows:
SQL Level API
The designers felt that their main goal was to define a SQL interface for Java. Although not the lowest database interface level possible, it is at a low enough level for higher-level tools and APIs to be created. Conversely, it is at a high enough level for application programmers to use it confidently. Attaining this goal allows for future tool vendors to “generate” JDBC code and to hide many of JDBC’s complexities from the end user.
SQL Conformance
SQL syntax varies as you move from database vendor to database vendor. In an effort to support a wide variety of vendors, JDBC will allow any query statement to be passed through it to the underlying database driver. This allows the connectivity module to handle non-standard functionality in a manner that is suitable for its users.
JDBC must be implemental on top of common database interfaces
The JDBC SQL API must “sit” on top of other common SQL level APIs. This goal allows JDBC to use existing ODBC level drivers by the use of a software interface. This interface would translate JDBC calls to ODBC and vice versa.
- Provide a Java interface that is consistent with the rest of the Java system
Because of Java’s acceptance in the user community thus far, the designers feel that they should not stray from the current design of the core Java system.
- Keep it simple
This goal probably appears in all software design goal listings. JDBC is no exception. Sun felt that the design of JDBC should be very simple, allowing for only one method of completing a task per mechanism. Allowing duplicate functionality only serves to confuse the users of the API.
- Use strong, static typing wherever possible
Strong typing allows for more error checking to be done at compile time; also, less error appear at runtime.
- Keep the common cases simple
Because more often than not, the usual SQL calls
used by the programmer are simple SELECT’s,
INSERT’s,
DELETE’s
and UPDATE’s,
these queries should be simple to perform with JDBC. However, more complex SQL
statements should also be possible.
Finally we decided to precede the implementation using Java Networking.
And for dynamically updating the cache table we go for MS Access database.
Java ha two things: a programming language and a platform.
Java is a high-level programming language that is all of the following
Simple Architecture-neutral
Object-oriented Portable
Distributed High-performance
Interpreted Multithreaded
Robust Dynamic Secure
Java is also unusual in that each Java program is both compiled and interpreted. With a compile you translate a Java program into an intermediate language called Java byte codes the platform-independent code instruction is passed and run on the computer.
Compilation happens just once; interpretation occurs each time the program is executed. The figure illustrates how this works.
| Java Program |
| Compilers |
| Interpreter |
| My Program |
6.7 NETWORKING TCP/IP STACK:
The TCP/IP stack is shorter than the OSI one:
TCP is a connection-oriented protocol; UDP (User Datagram Protocol) is a connectionless protocol.
IP datagram’s:
The IP layer provides a connectionless and unreliable delivery system. It considers each datagram independently of the others. Any association between datagram must be supplied by the higher layers. The IP layer supplies a checksum that includes its own header. The header includes the source and destination addresses. The IP layer handles routing through an Internet. It is also responsible for breaking up large datagram into smaller ones for transmission and reassembling them at the other end.
UDP:
UDP is also connectionless and unreliable. What it adds to IP is a checksum for the contents of the datagram and port numbers. These are used to give a client/server model – see later.
TCP:
TCP supplies logic to give a reliable connection-oriented protocol above IP. It provides a virtual circuit that two processes can use to communicate.
Internet addresses
In order to use a service, you must be able to find it. The Internet uses an address scheme for machines so that they can be located. The address is a 32 bit integer which gives the IP address.
Network address:
Class A uses 8 bits for the network address with 24 bits left over for other addressing. Class B uses 16 bit network addressing. Class C uses 24 bit network addressing and class D uses all 32.
Subnet address:
Internally, the UNIX network is divided into sub networks. Building 11 is currently on one sub network and uses 10-bit addressing, allowing 1024 different hosts.
Host address:
8 bits are finally used for host addresses within our subnet. This places a limit of 256 machines that can be on the subnet.
Total address:
The 32 bit address is usually written as 4 integers separated by dots.
Port addresses
A service exists on a host, and is identified by its port. This is a 16 bit number. To send a message to a server, you send it to the port for that service of the host that it is running on. This is not location transparency! Certain of these ports are “well known”.
Sockets:
A socket is a data structure maintained by the system
to handle network connections. A socket is created using the call socket. It returns an integer that is like a file
descriptor. In fact, under Windows, this handle can be used with Read File and Write File
functions.
#include <sys/types.h>
#include <sys/socket.h>
int socket(int family, int type, int protocol);
Here “family” will be AF_INET for IP communications, protocol will be zero, and type will depend on whether TCP or UDP is used. Two
processes wishing to communicate over a network create a socket each. These are
similar to two ends of a pipe – but the actual pipe does not yet exist.
6.8 JFREE CHART:
JFreeChart is a free 100% Java chart library that makes it easy for developers to display professional quality charts in their applications. JFreeChart’s extensive feature set includes:
A consistent and well-documented API, supporting a wide range of chart types;
A flexible design that is easy to extend, and targets both server-side and client-side applications;
Support for many output types, including Swing components, image files (including PNG and JPEG), and vector graphics file formats (including PDF, EPS and SVG);
JFreeChart is “open source” or, more specifically, free software. It is distributed under the terms of the GNU Lesser General Public Licence (LGPL), which permits use in proprietary applications.
6.8.1. Map Visualizations:
Charts showing values that relate to geographical areas. Some examples include: (a) population density in each state of the United States, (b) income per capita for each country in Europe, (c) life expectancy in each country of the world. The tasks in this project include: Sourcing freely redistributable vector outlines for the countries of the world, states/provinces in particular countries (USA in particular, but also other areas);
Creating an appropriate dataset interface (plus
default implementation), a rendered, and integrating this with the existing
XYPlot class in JFreeChart; Testing, documenting, testing some more,
documenting some more.
6.8.2. Time Series Chart Interactivity
Implement a new (to JFreeChart) feature for interactive time series charts — to display a separate control that shows a small version of ALL the time series data, with a sliding “view” rectangle that allows you to select the subset of the time series data to display in the main chart.
6.8.3. Dashboards
There is currently a lot of interest in dashboard displays. Create a flexible dashboard mechanism that supports a subset of JFreeChart chart types (dials, pies, thermometers, bars, and lines/time series) that can be delivered easily via both Java Web Start and an applet.
6.8.4. Property Editors
The property editor mechanism in JFreeChart only
handles a small subset of the properties that can be set for charts. Extend (or
reimplement) this mechanism to provide greater end-user control over the
appearance of the charts.
CHAPTER 7
7.0 APPENDIX
7.1 SAMPLE SCREEN SHOTS:
7.2
SAMPLE SOURCE CODE:
CHAPTER 8
8.1 CONCLUSION:
We try to dissipate the mist on the the locations of spoofers based on investigating the path backscatter messages. In this article, we proposed Passive IP Traceback (PIT) which tracks spoofers based on path backscatter messages and public available information. We illustrate causes, collection, and statistical results on path backscatter. We specified how to apply PIT when the topology and routing are both known, or the routing is unknown, or neither of them are known.
We presented two effective algorithms to
apply PIT in large scale networks and proofed their correctness. We
demonstrated the effectiveness of PIT based on deduction and simulation. We
showed the captured locations of spoofers through applying PIT on the path
backscatter dataset. These results can help further reveal IP spoofing, which
has been studied for long but never well understood.