Towards Green Frameworks for Digital Forensics Investigation

Transcription

1 Towards Green Frameworks for Digital Forensics Investigation Faculty of Computer Science and Information Technology, University Putra Malaysia. {alid, ramlan, Abstract Despite the fact that digital forensics involves strict procedures and complies with fixed regulations and principles, but as this paper presents, there are plenty of opportunities that can be practically employed in digital forensics to make this science greener. Virtualization can cost effectively reduce the number of workstations running forensic tools in the lab. Cloud computing and consolidating servers and storage devices in green data centers not only facilitate managing and securing services but also decline the number of required network and cooling facilities. Forensic labs can also be optimized with regard to environmental preservation. Using remote protocols and digitalizing paperwork procedures are environmentally helpful practices to accelerate investigation progress as well. Improving electrical power needs of labs and forensic devices is another issue that should be taken into consideration. Employing storage devices with optimal energy usage in digital forensics may highly reduce energy consumption. This paper study established green technologies particularly in information technology field and suggests a framework for implementing compatible techniques in digital forensics in order to reduce greenhouse gas pollutants, limit carbon emissions, and preserve the environment. Keywords: Green forensics, digital forensics, environmental preservation, forensic lab 1. Introduction Recent years have witnessed a global intention of employing environmentally friendly products and technologies. The most prominent computer hardware manufacturers are competing for using environmentally sustainable and the latest energy-efficient technologies in their products. Additionally, many companies and organizations are experiencing implementing green information technology (IT) [1]. Digital forensics, on the other hand, involves meticulous procedures, some deliberately redundant (e.g. duplicating data from digital evidence using different tools and storing several copies of that) to insure the accuracy of the investigation process. Workstations, forensic labs, and even software toolkits used in digital forensics, all, need to meet specific requirements. However a variety of green approaches and efforts might be adapted in digital forensics as well. This paper outlines the opportunities that can be taken for reducing environmental impacts of digital forensics in both forensic labs and crime scenes. It also encompasses challenges that confront with employing common green technologies in digital forensics. The remaining of this paper is organized as follows: Section 2 reviews virtualization and cloud computing, two notorious techniques being employed in green IT. It also delves into environmental conditions and electrical needs of forensics labs. Moreover, the section encompasses effective factors in energy consumption of storage devices. Section 3 proposes a framework for establishing the discussed methods in digital forensic labs. It also suggests some methods and techniques for implementing green digital forensic devices and forensic procedures. Section 4 analyses the proposed approach and the work is finally concluded in section 5. 2 Literature Review This section reviews the current state of the art of elements that affect greening digital forensics. These elements are divided into five perspectives as namely virtualization, cloud computing, environmental conditions of forensic labs, electrical power needs, and storage devices. Journal of Convergence Information Technology(JCIT) Volume 8, Number 2, Jan 2013 doi : /jcit.vol8.issue2.80

2 2.1 Virtualization As stated in Gartner Data Center Conference, virtualization can promote hardware utilization by 5 to 20 times and enables organizations to decrease the number of servers and consequently reduce the power consumption [1]. There are also some technologies can be employed for storage virtualization like IBM SAN Volume Controller (SVC) [2] that presents storage devices of a SAN coupled with a virtual pool as only one logical device [1]. In addition to server virtualization that lowers costs, improves resource utilization, and increases availability, client virtualization can also be employed for the same benefits [1]. In client virtualization, workstation is replaced with a machine that consumes less energy and computing power is moved into data center [1] which is further discussed in the next part. One of the challenges with regard to virtualization is as long as multiple operating systems (OS) and services are running on the same host, any security threat that exploits a vulnerability of one of the running OSs may affect other OSs and services as well. Additionally, if a machine that provides several services, rather than one, goes down, then all services hosted on the machine will be shutting down [3]. Gartner has estimated that, by 2012, 60 percent of virtualized servers will be not as secure as physical machines that they have been replaced with [4]. Liu et al. [5] propose that a different IP is assigned to each virtual machine (VM) running on a machine. Each of VMs should be also separated from the rest using distinct virtual LANs (VLAN) and the only way a VM to connect to another VM should be through layer 3 network devices [5]. Using routers feature firewall for transmitting data between VLANs can minimize the risk of being infected by malicious software (malware) attacking from a VM [5]. Even after applying this method still less network devices such as network interface controllers (NIC), cables, and switches are used [1]. 2.2 Cloud Computing Cloud computing is a model that enables convenient, ubiquitous, and on-demand network access to a shared pool of computing resources like servers and services which can be quickly provisioned and released with least service provider interaction or management effort [6]. In addition to promoting availability, cloud systems optimize and control resource usage (e.g., storage, processing, and bandwidth) by leveraging a measuring capability suitable for the type of service [6]. Cloud computing environments are twofold, termed, public and private [7]. In public cloud computing environment, users communicate with servers using the Internet while private cloud computing environment is isolated from the outside world by means like firewall and only authorized users and connections are allowed to have access to resources [7]. The common specification of two types is rather than equipping numerous workstations, strong servers with optimized configuration are run and managed. There are three types of cloud computing services as follows: (1) storage as a service, (2) processing as a service, and (3) software as a service [7]. In storage as a service as its name suggests, user stores their data in the cloud while in processing as a service user outsources intensive tasks to cloud [7]. Software as a service involves both of these services and allows user to put all their tasks to cloud [7]. Baliga et al. [7] compared these types with regard to transport, storage, and processing which their results is presented in Table 1. Table 1. High Energy Consumption in Cloud Computing with Regard to Cloud s Type and Three Factors Factor Software as Storage as a Service Service Processing as a Service Transport High frame rates High download rate Never Storage Never Low download rate - Processing Few users per server High download rate Medium to high encoding per week

3 Server virtualization, client virtualization, storage virtualization, and also cloud computing make all servers be placed in data centers. The most energy per square foot is consumed in data centers of organization which mostly come from two parts namely, servers and cooling system [1]. Lamb [1] defines green data center as a repository used for storing, managing, and disseminating data in which computer systems and other corresponding mechanisms like lighting and electrical are optimized to maximize energy efficiency and thereby minimize environmental impact. Power Usage Effectiveness (PUE) and Data Center Infrastructure Efficiency (DCiE) are two metrics used for determining the energy efficiency of data centers, although they do not cover the whole scope of data center [1]. Equations (1) and (2), respectively, demonstrate how PUE and DCiE are calculated [8, 9]. It should be noted that the total facility power includes all facilities employed for supporting the IT load. Total Facility Power PUE (1) IT Equipment Power IT Equipment Power DCiE (2) Total Facility Power 2.3 Environmental Conditions of the Lab There are requirements specified for building and developing a digital forensic lab. These requirements and standards are stated in ASCLD/LAB and ISO/IEC One of the standards that the ASCLD/LAB requires for a laboratory to have is to provide a comfortable working environment for the employees [10]. It is a must to follow these standards as stated. However, there is no environmental consideration stated for developing a digital forensic lab. Some issues have been highlighted in regarding to the environmental concerns and also in order to satisfy the lab requirements. One of the issues here is the cooling system in a lab. Cooling system is important for digital forensic labs because of temperature balance and air movement. Cooling system consists of air conditioners. In order to prevent the workstations and servers in the lab from overheat and also to maintain a balance of temperature in the lab, air conditioners are used [1]. However, high amounts of energy are consumed by air conditioners and provide no green solution or green promoting. To save the cost of the electricity used by digital forensic lab, cooling fans or a good ventilation system is installed and can decline the waste of energy [1]. Unlike normal chemical lab that requires extensive ventilation and air condition which consume more energy, digital forensic lab s heating, ventilation, and air conditioning (HVAC) systems can be designed to look alike of a normal office that has a low-velocity air handling system, resulting in substantial energy savings [11]. A digital forensic lab needs a good lighting system to help the examiner to concentrate in their investigation especially for the video examination. Lighting control can enhance the focus ability with different light quality sources as well as the need for dimmable lighting [11]. In general, normal lighting bulbs and tubes usually consume more energy than needed to light up. It is advice that digital forensic lab should use energy saving light bulbs or light tubes. A proper energy saving lighting bulbs and tubes have the certification from the Energy Star program that promotes in protecting the environment and save money [25]. So, to provide a better lighting around the surrounding area in the lab which also consume less energy as well as produce less heat, energy saving light bulbs is used [12]. Using energy recovery as an energy code for digital forensic lab is a way to promotes green initiative. These labs capture heats that are produced by the lab exhaust to preheat the air outside of the lab, thus preventing energy wastage [12]. This reduces the release of energy waste as well as reducing the energy consumption in the lab. 2.4 Electrical Power Needs One of the big concerns related to the digital forensic lab and green computing is the need for power supply. A digital forensic lab consumes a huge amount of electricity because of the workstations, servers, lightning and cooling system and other electrical equipments. There are some effective

4 methods to be employed to decrease the environmental damages cause by the huge consumption of electricity. Computers belonged in organizations are stated to have been used fully only for four hours. Aside from the four hours, these computers have been left idled for the rest of the working hours and are still consuming electricity [13]. To lower the electricity usage in the organizations, it is stated that it is better to use a different type of computer. This particular type of computer can offer not only low power consumption usage but can also offer a better speed performance than the normal computers [13]. For windows-based computers that have low power consumption are offered by companies such as Intel and Hewlett-Packard (HP). While switch on, the computer can be set to go into low-power state after a short period of time of not using it. Also by setting, the computer can automatically shut itself down after awhile [14]. Organizations may have administrators or IT technical staffs to do remote shut down for the computers after working hours or perhaps, schedule automatic shut down at a certain time [15]. It is believed that generally a computer uses roughly of watt of power to operate in an hour depending on its activity by the user. In that one hour, there is at least of carbon dioxide (CO2) emissions per hour (gr). For every one KWh of electricity used, there is a 650gr of CO2 emissions [16]. Power supply units (PSU) are the units that convert the AC and supplies Direct Current (DC) that is needed to power the computers and servers with its components. Normal power supply unit is not energy efficient and there is an amount of energy waste as heat. 80 PLUS promotes efficiency in energy consumption in the power supply units. It performance specification requires the power supplies in computers and servers to be 80% or greater energy efficient at 20%, 50% and 100% of rated load with true power factor of 0.9 or greater [17]. Table 2 shows how a power supply unit will be certified according to the percentage of rated load and the internal non-redundant. It also shown that an efficient power supply unit which only wastes 20% or less energy as heat can help in reducing electricity consumption as compare to the less efficient power supply unit [17]. There is a report of news which entailed that increasing the heat in the data center of the crime lab can saves energy and promotes green initiative in the lab. It also reduces the electricity cost by roughly 15% [18]. Another solution for providing electricity and at the same time to go green, renewable energy is the answer. Renewable energy comes from natural environment such as sunlight, wind and tides. The examples of renewable energy that can be used as power supply to the digital forensic lab are the solar energy, hydropower or the wind-generating-power. By the use of photovoltaic panels to absorb the sunlight, electricity can be harvested from solar energy [13]. Table PLUS Certification of Computer Power Supplies 80 PLUS Certification 115V Internal Non-Redundant 230V Internal Redundant % of Rated Load 20% 50% 100% 20% 50% 100% 80 PLUS 80% 80% 80% N/A 80 PLUS Bronze 82% 85% 82% 81% 85% 81% 80 PLUS Silver 85% 88% 85% 85% 89% 85% 80 PLUS Gold 87% 90% 87% 88% 92% 88% 80 PLUS Platinum 90% 92% 89% 90% 94% 91% 2.5 Storage Devices Hard disk drives (HDD) are the most frequently used device being employed for storing data and HDD with high capacity typically use higher energy. There are models of HDDs in the market that use less energy and makes less heat. For instance, a Western Digital HDD consumes 5 watts less than a normal HDD [13]. Furthermore, storage technologies like NAND flash memory based SSD (Solid State Disk) in comparison with traditional HDDs waste less energy and at the same time provide more reliable services [19]. Additionally, there are technologies which optimize power usage. MAID (Massive Array of Idle Disk) is a good example that switches off idle HDDs [19, 20]. Using tapes instead of hard disks for making backups is more optimal as tapes have more storage volume at the lowest cost [1]. As mentioned previously, storage field can be optimized by using storage virtualization. Overall,

5 centralizing reduces the number of required HDDs and consequently it enhances the efficiency of storage devices with regard to energy consumption [1]. 3 Proposed Approach Our proposed framework is composed of six parts as follows: Virtualization and consolidation The concern of environmental conditions of digital forensic labs Electrical needs of the digital forensic labs and its equipments Storage devices Forensics devices Green procedures that can be adapted by the employees in the digital forensic lab 3.1 Virtualization and Consolidation As a matter of fact in digital forensics, investigator has to deal with a variety of software programs and tools. In addition to different OS that may be required to be employed in each investigation, many software forensic tools need specific OSs. Also installing multiple forensic tools with similar functionality (e.g. mobile phone forensics tools) on the same OS is deprecated [21]. The most elegant way to deal with these issues is employing virtual machines (VM) using products like VMware [22] and Microsoft Virtual PC [23]. By virtualizing, multiple OSs and several forensic tools can be installed and run on the same workstation. It should be also taken into consideration some digital forensic tools may not be able to work properly on virtual environments. In order to strengthen the security of each OS and fulfill requirements of forensic labs like isolating LAN from external networks such as the Internet, each VM should have its own IP address and be assigned to a separate VLAN. Therefore, all packets between virtual OSs have to pass via routers feature firewall functionality. Employing private cloud computing with optimal and at the same time powerful severs that provide services to multiple forensic investigators and allow them to use the resources remotely from workstations consuming low energy can significantly reduce the energy consumption. It also consolidates services and data and as a result it eases managing and securing them. Moreover, the required digital forensics facilities like hard disk write protection tools are declined as they can be installed only on servers rather than all workstations. However there are issues that should be taken into account. As Table 1 demonstrates, in cloud computing energy consumption is dependent upon cloud type as well as the number of users. For instance, Software as Service is suitable to be used in forensic labs that have large number users. There are also some forensic devices specifically developed to centralize storing and managing forensic data. Forensic Network [24] is an exemplar of this kind of devices. It is a file server operates as a central storage service of forensic images. Taking images and processing are done by clients and Forensic Network hosts images and investigation case works [24]. Thus several investigators can concurrently access to cases and images files from their workstations without needing to copy and duplicate information [24]. As long as employing either virtualization or cloud computing will result in consolidating and placing fundamental servers in data centers, improvement in cooling efficiency of data centers can conserve a considerable amount of energy. Furthermore, metrics like PUE and DCiE can be employed for finding the efficiency of data centers regarding optimal energy consumption. 3.2 Environmental Conditions of the Lab As stated before, the standards and requirements needed for having a digital forensic laboratory must be followed and satisfied. This does not mean that there is no consideration for environmental conditions to be fulfilled for each of the requirements. The heating, ventilation and air conditioning systems of a digital forensic lab can be designed similar of a normal office that requires low-velocity air system. Low-velocity air system consumes less amount of energy. Ventilation system can be

6 installed for the digital forensic lab rather than using air conditioners, thus resulting in reducing the green house effect. Air movements are promoted by the use of ventilation system which can also keep the lab from being stuffy and hot. Servers and workstations in the lab can be prevented from overheat in the lab. Unlike air conditioning system, the usage of energy is lesser and there of no promoting of energy wastage by the ventilation system. Furthermore, to help in reducing the energy consumption of the lab, an energy saving lightning system should be installed. However, it is time consuming and quite costly to install these green bulbs or tubes in the lab. The Energy Star certified light bulbs and light tubes are proved to save energy and money. It can show that it really consumes less watt to light up and minimum release of energy wastage known as heat. Good lightning effect like the daylight which makes the lab a comfortable environment is maintained by these energy saving bulbs and tubes. Other than less energy consumption, these bulbs and tubes have a longer span of life then the normal ones. To maintain the energy consumption at a certain level and also to reduce the waste of energy on the digital forensic lab, energy recovery can be employed. By promoting the use of energy waste from the lab exhaust, energy recovery is a plan to these wastes for other purposes. 3.3 Electrical Needs A huge amount of power supply is and can be consumed by one digital forensic lab to run the equipments inside the lab. By employing windows-based workstations which have the option to go for low-power state and will eventually automatically shut down after being left unused for a certain period of time can help in reducing the usage of electricity in the lab. Intel and HP can provide these workstations for the lab. A few administrators should be employed by the lab to perform a checking and remotely do computers shut down that are left switch on after the working hours. Energy consumption can be reduced by switching off the unused workstations. It is recommended for digital forensic labs to get certified for 80 PLUS certification. It is not only to prove that digital forensic lab can be energy efficient but it definitely can promote green computing. By getting certified, any size of a digital forensic lab can roughly know how much energy cost that can be saved annually. It is possible for the digital forensic lab to slightly increase the heat of the servers room to reduce the electricity consumption and also reduces the cost of the electricity. It is recommended for the digital forensic lab to have a tool to monitor the usage of the electricity by the servers. There are many available tools and software that can manage the energy consumption of servers. A free cooling tool known as Power Configuration Efficiency Estimator is developed for calculating and estimating how much does the energy cost and can be saved by using the outside air to circulate the servers room [26]. It is advisable that digital forensic lab should adapt low energy consumption equipments such as computers and HDDs. Although the consumption of energy has been lessen, it will have a better performance than the normal energy consuming equipments. To handle the power supply more wisely for the digital forensic lab is to install and have a renewable energy system. It is suitable for a digital forensic lab to have a solar power system to provide electricity to the lab since sunlight is the most available renewable energy anywhere. Digital forensic lab that is located in a windy area can employ wind power system where the electricity is harvested with the help of the wind. Not only renewable energy cost lesser than normal power supply, it promotes green solution to the environment. 3.4 Storage Devices Duplicating data stored on digital evidence and keeping several copies of them is an important stage in any digital forensics investigations. Therefore, using appropriate storage devices that consume less energy like modern HDDs and NAND flash memories can significantly reduce the overall power consumption in digital forensic investigations. Workstations especially those connected to cloud computing environments do not need to have HDDs with high capacity since HDDs with higher capacity consume more energy. Optimizing energy consumption using technologies like MAID is helpful for those servers of forensic lab that need large disk arrays. Moreover, backup servers should store data on tapes.

7 3.5 Forensic Devices To the best authors knowledge electrical energy is almost the only power supply of existing forensic devices. Consequently replacing energy sources of these devices with renewable energy sources can effectively reduce environmental impacts. Additionally, as far as possible instead of using hazardous materials, recyclable ones should be employed. Batteries are an exemplar of these materials. Equipping digital forensic devices like data acquisition tools with remote functionality can speed up the investigation process and at the same time it reduces unnecessary traveling. Many manual paperwork tasks such as chain of custody forms can be digitalized using mobile applications run on tablets or smartphones that are already carried by investigators. Digital signature, automatically calculating hash strings, recording date and time etc. all can be easily included in these applications. 3.6 Green Procedures In digital forensic lab, it is a common practice for the employees to print out forensic reports and other materials. However, in order to promote green digital forensics, it is highly recommended for the employees in the lab to adapt a digital-like resource such as sending the forensic reports through , instead of printing out a hardcopy of it. This does not only promotes the less usage of papers but also provides initiatives to go green in the employees of the lab. When it is necessary to use papers for printing, it is advisable that the both sides of the papers are use. A set of new regulation that required the employees to switch off the computers when it is not in use can be enacted in the digital forensic lab. The new regulation should not only involve switching off computers but also includes other equipments such as air conditions, air ventilations, lightning system, scanners, and etc. The new regulation can reduce carbon s footprint of the lab and reduce energy consumption in the lab. Thus, it can cut the cost of electricity of the lab. Training should be provided to the employees in the lab to increase the awareness of going green and the benefits of being green. The employees in the digital forensic lab should be known of the consequences that can be done the amount of CO2 released by the lab into the environment. 4. Analysis of Proposed Framework Virtualization can reduce the number of workstations, NICs, cables, etc. that are needed to be installed in forensic labs. It is also a secure approach especially if each VM is separated from other VMs using different IP addresses and VLANs. Moreover, virtualization prevents potential conflicts between forensic software tools since two tools with similar functionality can be installed on two different VMs. However as mentioned earlier there are forensic tools that are not capable of being run in virtual environments. Cloud computing, is another effective way for reducing energy consumption by consolidating servers and data. It makes managing, securing, and maintaining servers easier. Since servers are consolidated in data centers rather than being distributed in different parts of organization s building, optimizing cooling systems and the structure of data center can noticeable decline energy consumption. However cloud computing may not be always an optimal way for greening digital forensics. While medium to large forensic labs can economically and environmentally take advantages of that, but in small forensic labs with fewer users the cost of the implementing cloud computing environment should be thoroughly considered. There are many ways to promote green solution in the digital forensic lab. This can be done by employing a well planned ventilation system for air movement and cooling, lightning system and energy recovery plan. In a long term run, a huge amount of released carbon s footprint can be reduced significantly in the lab as these systems consume less energy. Consuming less energy means promoting less burning of bio-fuel that produces carbon s footprint. Not only it does reduce carbon s footprint of the lab, it also reduces energy cost and prevent energy wasting. Proper ventilation system and lightning system can provides comfort to the examiners in the digital forensic lab as well as promoting better concentration and focus in performing their jobs. By using computers and HDDs that have low power consumption than the normal ones, the electricity usage in the lab should be reduced also. It is noted that these low power consuming equipment can perform

8 better than the normal ones. Thus, this will not affect the quality work of a digital forensic examiner for worse but for better quality. Since the low power consumption computers can perform in a better speed, there is possibility that the time duration of an examiner to investigate digital evidences can be shorten. This can results in increasing of productivity in the digital forensic lab. Storage devices are essential devices used in each digital forensics whether in crime scene or forensic lab. Using proper devices is very effective in decreasing energy consumption. Another effective solution for making digital forensics much greener is to make use of renewable energies as power supply for digital forensics lab and forensics devices. It also helps in reducing the emission of green house gas, which is CO2. CO2 gas is the main emission when burning of any bio-fuel and oil for energy supply. Although installing a renewable power system can be quite costly such as a solar power system, but in a long run term, renewable energy can proves reducing cost of energy, minimum wasting of energy and most of all, no carbon s footprints. It is very clean and friendly to the environment unlike the burning of fuel. Equipping mobile forensic devices with remote access and using secure protocols for transmitting data may reduce travelling of investigators. Instead of using papers for recording investigation process tablets can be used to facilitate investigation progress. It also enables investigators to remotely connect to forensic devices and transmit data. Applications run on tablets, smartphone, or mobile forensic devices can use hashing algorithms for validating data in each transmission. Adaptation to greener new procedures in the digital forensic lab would take certain duration of time. The green procedures should be done step by step in a time for the employees in the lab to adapt and use to it. The effects of employing green procedures may not be immediately seen but in a certain period of time, however they eventually result in outstanding outcomes. Green procedures can help in reducing the spending of the lab to buy papers and such. It even encourages the employees in the lab to fully utilize the facilities that are provided in the lab properly. The examples of the facilities in the lab are computers, internet and telephones. 5 Conclusion and Future Work Virtualization is an elegant solution for decreasing the number of workstations and accordingly declining energy consumption. Cloud computing and consolidating servers and services, all, are, appropriate for medium to large forensic labs. However, there are factors like licensing that needed to be taken into consideration. Environmental conditions should be considered in digital forensic labs as it is important to promote green resolutions. It does not matter what size or type of the digital forensic lab is, as in a long term run, it can slowly adapting to these environmental conditions to reduce carbon s footprint. The proposed framework in the paper may not be the best but in the future, there is always a better solution that can be adapted into the digital forensic lab for the purpose of being environment friendly and also promoting the idea of going green. To run every equipments inside the digital forensic lab, huge amount of power is important to power up these equipments. Because of this, the lab is very dependent on the power supply. To reduce the huge energy consumption of the lab, low power consumption computers and HDDs is highly recommended to use. Switching off unused equipments in the lab can promotes lesser energy consumption. There will always be a better product that consumes lesser energy than the previous product in the market. These new products can be used in the forensic lab to further promote of less energy consumption. To further promote the green solution in digital forensic lab, renewable energy system can be employed which has absolute no energy wasting and no emissions of green house gas. There should be more encouragement of the renewable energy usage for the digital forensic lab as it can also reduce the energy cost of the lab. Techniques that can be employed to make hardware forensic tools remotely available will be encompassed in the future for use. It is discussed in this paper that digital forensics is highly relying on storage devices and when suitable consumption of energy is use, it can therefore reduces the energy consumption. Furthermore, digital forensic investigation can become greener by changing the power supply of forensic equipments from normal electricity to renewable energy. Another suggestion to reduce carbon s footprint is to adapting green procedures in the digital forensic lab. Certain duration of time is needed for the employees in digital forensic lab to become accustomed to the new procedures. But, outstanding results can be seen after that period of time which reduces greenhouse effect and promoting green digital forensics. It may help in reducing costs of electricity of the lab. The green procedures that were proposed for the framework can still be revised for a better adaption in the future in the digital forensic lab. Improving

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