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CSC8421 Network Security Oz Assignments
If we talk about the networkcommunication, it becomes the most important part of the human’s life in today’s time.Moreover, become the most important part of the business and industries. All have become dependent upon the network or internet for every small work. For the communication with the use of the internet, the user has to require the use of the IPv4 address and it has exhaustion.With that, the network comes under the attacks of the hackers and new threads are arise into the system.(Ellingwood, 2014)With the attacks, the important data and information are lost or comes under the control of the hacker. The internet services are open to everyone into the world. With the open network, it is easy to hack and attack the network.(Craft, 2011).Moreover, for the security of the system, there is various type of solution have found and the major solution is a firewall. This method is used to reduce the traffic onsever and provide the required traffic only to the server. If we talk about the firewall, it is available for both hardware and software.Moreover, if we compare both then the hardware one I the strongest tool as compare to the software. Because with the use of the hardware device it provides the more strength to the device as compared to the software tool. Some other factors are also available into the which affect the performance of the tool. Both in today’stime, many industries are using the software to protect the network for the use of the unauthorized use of the system (Brown,2014)
All above is the scenario of the internet services and their uses. Now the other solution to protect the network, the user can use the iptables, this tool has mostly used into the Linux system. Many features that are available on the firewall have also provided by this iptables, and other than this some features, which have not supported by this because of the support system that have used with this iptables. It is something related to theuser to configure the list of tables into the systems. After creating the tables now the tables are added to the configuration of the system and then start the use of the system as the filtering the system or the network access according to the rules provided by the Linux system. It can be used for both IPv6 and IPv4 systems and it can be configured and change the setting according to the to the network requirement.
In the report,the details about the iptables, configuration and how this can be implemented to the system and other than this use the various references of the journals and research papers are describedin the report.(Omin, 2017)
This part of the report deals with the various researched were done for the tables and various result and other information which are described in the research papers and journals.
1. Refer to the journal “Implementing iptables using a programmable stateful data plane abstraction” written by the Luca Petrucci. It provides the details about the type of the how the iptables have to implement the system with the use of the programmable data. Different type of tools are used for that are also mentioned in the journal. Other than this in the last, it provides the details about the future work, which can be done over the iptables (Petrucci, 2017)
2. Refer to the journal “Verified iptables Firewall Analysis” written by the Cornelius, it provides the details about the iptables. How this can be used as the system firewall. It defines the firewall work and after that, it provides the related work to the iptables. It provides the details about the network system IPv4, IPv6,and implementation of the iptables. Different type of the network layers explained into the journal (Diekmann, 2016)
3. Refers to the journal “Performance Evaluations of Iptables Firewall Solutions under DDoS attacks”this journal details with the DDoS attacks and the solution of this attacks with the use of the iptables. It provides the details of the different attacks and then provides the details of the DDoS attacks and the iptables used as the firewall system into the network (Šimon, 2015)
4. Refers to the journal “Design and Development of a Framework to mitigate DoS/DDoS Attacks Using Iptables Firewall” it also deals with the DDoS attacks and the DoS attacks by the hacker to get the information of the user.To overcome with the attacks iptables used as a firewall system to protect the user device from the attacks. It provides the details of the designing part of the framework of the system (Chatterjee, 2013)
5. Refers to the journal “Acceleration of IPTABLES Linux Packet Filtering using GPGPU”. It provides the details about the iptables and its use. How the iptables is related to the Linux system and how the system is work to secure the device from the various attacks. Different methods of implementation of the iptables into the device, other than this it provides the details of the effect of this iptables system into the device of the user (Karimi, 2013)
After reading all the research papers and journals that are described above, various type of the functionality of the iptables and methods, whichhave used to implement this system are described.
For describing the details and working of the iptables,let us take an example of the iptables commands.
# iptables –t nat –A PREROUTING –I eth1-p tcp - - dport 80 –j DNAT - - to – destination 192.168.1.3:8080
The above written is the command, which is related to the iptables and this,cannotbe understood by the normal person by just reading the commands, so this command is described below:
Details of the commands
It is used to DNAT the goal.
This command is used to verify the packet of TCP/IP related to the protocols.
This works for the nat tables
This command is used to change the IP address from original to the required.
The commandis the destination of the TCP protocol.
This command is used for the verify the packet that is coming from the network.
It is used for appending the rule in its PREROUTING chain
After reading, the examples now consider the main rules and the techniques that are used to define the iptables.
There are different types of chains that are attached to the hook points, for developing the user can add the sequence of the rules into the hooks point that is present in the tables. All the hooks, which are present in the tables, will be used to define the path or the methods by which they are filtering the data or information that are present in the packets.If all the rules and followed by the packet and then the packet will working according to the rules which were listed in the tables.
The below shown the figure related to the packet traverse system which was present into the network security address, translation scenario.In addition, this can be used as the system for the table nat.
Figure 1Software model for ASF
After that now filtering the packet. The below image shows the process of the filtering the iptables with the use of the hook point.
Figure 2 hook point use
After that, the below image shows the mangling process for the packet processing into the system.
Figure 3 Packet flow and hook point
Refer to the hook point it is the most important thing into the iptables. Because it is used to decide the behavior of the rules into the table. It also sued to decide and separate the processing part of the iptables. Different types of rules are available for which for configure the table and the systems. Some rules are used to blocking the traffic and some used for forwarding the traffic. For that, the tables arecreated to decide the work for the rules. In the below tables, different hooks points are defined along with the work for that packet.
Table 1 HOOK TABEL
Details of the hooks
It is used to allow the system work packets before it will give to the system of thelocal process.
It allows the system to work and use the packet before arriving the network interface.
It allows the system to sue the packets and make the flow into the system, in the flow all the details come from the one interface and leaves to the other interface.
It allows the system to work and use the packet before the leaving the network interface.
It is used to allow the system work packets before it will give to the system of thelocal process.
Tables that have used into theiptables:
In the above part of the report, provide the details of the hook points thatare used in each configuration for the iptables.Alternatively, command line that is used to define the different tools. Other than this the iptables have three different type of built-in tables, all the tables are used to process all the function that provided by the packets. Different type of tables are listed below:
The above tables are followed some pre-defined hook points that are used to configure the iptables. In the below table provide the details of the all the tables.
It is aspecial type of the table, which have some special features and methods, which are used to change the IP packets that are coming from the network traffic. It can be used to set the different type of afunction into the IP packets. Chain for this built table is:FORWARD, INPUT, OUTPUT, POSTROUTING, and PREROUTING
This table is used for the filtering the traffic running on the server, it is the most important part of the system. It can be used to track the dynamically built connections and also used to redirect the connections. It works on the destination of the IP address. The chain follows::OUTPUT, POSTROUTING, and PREROUTING
This is the main part of the processing the configuration. It is used to allow and deny the traffic as per requirement. It also followsthe rules and chains of the table. Chain for this table:FORWARD, INPUT, and OUTPUT
Other than this, now let us see different types of chains that are available into the system. As we consider the chain system, it is the most necessary part into the iptables.Some type of the chains has followed each of the tables that are present into the iptables.These chains are empty for some or all the hook points, the hook points are the predefines points that are described in the above tables. After getting the default chain, now the user can create the other chains with the use these chains for the iptables. The main use of the chain system is that to find out the real working of the IP address and the path, which followed by the system for the iptables. It is used to find out the verifying process of the chains that are present in the system of iptables. There are total two different types of the process available for the chains which have to follow the system these are the DROP and ACCEPT. For the use of the system, the build in theset as the by default accept the argument present into the system. All the other police that are made by the user is the complex in nature and it has the predefined keys have to return and after that, no further changes are available into the system.
After the chain flow now, consider the packet flow of the system, it the importance of the system for the working terms. The movement of the packets is followed by the first step. In this, the packet is moved to the chain after that the chain transfer the packet into the rules of the packets after that follow all the configuration system.If the information present into the packet is not matched to the system then the packet is moved to the next line of the chain. In the next line, also the system does not match any kind of information then the default value action is taken to the packet.
Table 3other network flow of packet
Table 4local network flow of packet
Table 5 packet flow
Table 6packet flow
Now refer to the term target that is used into the iptables, this term is nothing but just as the outcome of the system, the outcomes based on the IP match into the system. There are total four different type of outcomes are available into the system. All the listed and described below:
This is used to send the packet to the required place. This means that the present code is not available into the system.
This is the single output by which the packet is moved for the next operation into the system. After that, this will be stopped for the next steps into the systems.
It is used in the system that is the created by the user itself. It is used to stop the working of the packets and start the movement of the packet if the system matches the address.
It is used to stop the process of the system when the system is not matched into the system.
Application of theiptables:
Different types of the iptables tools are availableto the market. The use of the iptables is the over the server only. It does not use the workstation because the work of the workstation is changing according to the customer demand. Other than this the server is working for the simple type of works.Therefore, for them, the protection is required. Different and important applications of the iptables are described below:
- Port forwarding
- Network address translation
- Packet mangling
- Connection tracking
- Packet filtering
Methods and solutions
This part of the report deals with the methods and others factors that affect the system, it is the cost-efficient method and it can be easily developed into the systems, and the run over the internet serves. This iptables are provided the various system applications tools. Working of the iptables depends upon the operating systems. Woking of this effect over the different operating systems.
The location of iptables depends upon the application that is using to configure the iptables into the systems. The below image showsone of the examples of the iptables installation of the firewall.
Figure 5 test network
If want to understand the Woking of the iptables than having to read and understand the running of the packets over the server. The below flow diagrams show the configuration of the iptables with the use of different type of chain machines.
Figure 6 system ofiptables
1. As refer to the above figure than it will show that the packet comes through the incoming part of the interface and after that goes to the processing part with the help of PREROUTING chain. Before any rules are applied to the packets, the Nat destination is used into the packet. The PREROUTING chain is followed one-to-one mapping into the static destination Nat into the packet.
2. After this process is completed, the packet goes into the routing decision, at that part the decision is taken for considering the details, which are present in the packet. After this the input chain does the next process, this process is only done if there is same IP address present into the IP packets and the local address. After matching the IP address now the packet is transferred forward into the local machine to process the other part as per written into the packet. All the outputs and the other process in the ends go with the help of output chain.
3. Take the condition if the packet is not reached to the destination, at that time the forward chain rule is followed. This is the process sued to check all the packets one by oneafter that put the packet into the required place. After that, the packet will be dropped if the transferring of the machine is not allowed.
4. The output part of the report deals with the crossing the packets which is related to the machines. These are all the packets that are used to replay any kind of query that was generated by the machine itself. After that, all the packets are checked by when the process of the actual IP packet is converted. With this, the packet is reached to the correct order and place.
5. The POSTROUTHING chain is used to check the outgoing packets from the system. Nat is the main function used into this chain system after following all the rules. Other than this it will use for hiding the source.
The iptablesis the mainly used on the server applications. The main function of the application is that to protect sever or the traffic over the internet.This is mainly used to protect the server;this is the mainly used over the internet. As the internet technologies increases, the number of attacks on the internetservers also increase. For protecting the server over the internet server the iptables is used and it the cheapest way to protect the server. Refers to the other devices, software and hardware than all other devices as the quality of the services increases than the cost and the size of the system also increase.Whereas the iptables will be same for all type of services, the demand of this iptables will be anincrease in the futures.
This report provides the details of the iptables and use of the iptables and how well this function is Woking into the system. The main working of the systems is depending upon which type of operating system is used by the organization because it generally worksfor the Linux system. It is cheap as compared to the other devices,other than this in the report different type of chains and hooks are used to deliver the Woking of the system. In the future, the demand of the iptables is increased because of the quality of network security and the and the cheapest into the security devices. The iptables is working as the firewall into the systems.
1. Petrucci, L., Bonola, M., Pontarelli, S., Bianchi, G. and Bifulco, R., 2017, April. Implementing iptables using a programmable stateful data plane abstraction. In Proceedings of the Symposium on SDN Research (pp. 193-194). ACM.
2. Diekmann, C., Michaelis, J., Haslbeck, M. and Carle, G., 2016, May. Verified iptables firewall analysis. In IFIP Networking Conference (IFIP Networking) and Workshops, 2016 (pp. 252-260). IEEE.
3. Šimon, M., Huraj, L. and ?er?anský, M., 2015. Performance evaluations of IPTables firewall solutions under DDoS attacks. Journal of Applied Mathematics, Statistics and Informatics, 11(2), pp.35-45.
4. Xu, J. and Su, W., 2013. Performance evaluations of Cisco ASA and linux IPTables firewall solutions.
5. Chatterjee, K., 2013. Design and Development of a Framework to Mitigate DoS/DDoS Attacks Using IPtables Firewall. International Journal of Computer Science and Telecommunications, 4(3), pp.67-72.
6. Diekmann, C. and Hupel, L., 2016. Iptables-Semantics. Archive of Formal Proofs, 2016.
7. Karimi, K., Ahmadi, A., Ahmadi, M. and Bahrambeigy, B., 2013, December. Acceleration of IPTABLES Linux packet filtering using GPGPU. In Symposium on Computer Science and Software Engineering (CCSE), Tehran, Iran.
8. Ellingwood. J. 2014, How the Iptables Firewall Works. Viewed on 23 October 2017, https://www.digitalocean.com/community/tutorials/how-the-iptables-firewall-works
9. Craft. N. 2011, Linux: 25 Iptables Netfilter Firewall Examples For New SysAdmins. Viewed on 23 October 2017, https://www.cyberciti.biz/tips/linux-iptables-examples.html
10. Brown. K. 2014, The Beginner’s Guide to iptables, the Linux Firewall. Viewed on 23 October 2017 https://www.howtogeek.com/177621/the-beginners-guide-to-iptables-the-linux-firewall/
11. Jithin. 2017, what is iptables? How to manage iptables? Viewed on 23 October 2017, https://www.interserver.net/tips/kb/iptables-manage-iptables/
12. Rackspace. 2015, Introduction to iptables. Viewed on 23 October 2017, https://support.rackspace.com/how-to/introduction-to-iptables/
13. Omin. C. 2017, Iptables: An Introduction, Viewed on 23 October 2017, http://cyberomin.github.io/devops/2017/01/25/iptables.html
14. Smith. H. 2017, An Introduction To Iptables: The Linux Firewall - Part 1. Viewed on 23 October 2017, https://blog.100tb.com/an-introduction-to-iptables-the-linux-firewall-part-1