The security issues in cloud computing
Abstract
The cyber security field consists of many sections that create the cyber space collectively. One such component is cloud computing. Cloud computing takes a very significant part in the cyber space in the present. Therefore, discussing the cloud computing issues is very important. The objective of this report is to address some of the most critical issues in cloud computing. In order to complete that objective, first cloud computing and the fundamental nature of cloud computing issues are introduced. Then, the evolution of cloud computing and cloud computing issues are discussed by mainly focusing on Virtualization security issues and Data storage and computing security issues. The report also covers the future development of the cloud computing issues along with the counter measures. As discussed in the paper, cloud computing is and will continue to grow to be used due to the many benefits it offers. Therefore, it is important to focus on improving the cloud computing security.
Key terms: cloud computing issues, virtualization security issues, data storage and computing security issues
1. Introduction
Cloud computing can be known as providing various services that people can use throughout internet. The users can access information which is found without physical contact in the cloud or a virtual space that is why this method is named as cloud computing. It provides many resources like servers, networks, storage, applications, software and services. Nowadays people and businesses use cloud computing for many reasons including increased productivity, cost cutting, speed and efficiency and performance. Cloud services provide users the ability to store files and applications on remote servers. When it is needed, users can access that data through internet. It means users can access in any place. Cloud computing permits the user to work remotely. Because of this people who use cloud computing can access their data, work, and applications in whichever device which users can connect internet, any place in the world. Cloud computing provides many services with multiple functions including: Emails, generate and trial apps, analyze data, storage, backup, and withdraw data, audio and video streaming, on demand software delivery. Cloud computing is using many different organizations within a vast range. There are many different clouds. The first is Private cloud, and here cloud infrastructure is supported by a single entity containing various users (e.g., business units) for exclusive use. It can be owned, controlled and managed by, or some combination of the company, a third party and may reside on or off site. The second is Community cloud, where cloud infrastructure is provided for absolute use by a common user group of organizations with mutual interests (e.g., project, compliance). It may be owned, controlled, and run by one or several community groups, a third party, or any composition thereof, and it can prevail on or off premises. The third is Public cloud and the cloud infrastructure is given to the general public for free use. It can be owned, controlled, and functioned by, or some composition of, any type of organization. It inhabits at the premises of the cloud provider. The fourth is Hybrid cloud here the cloud infrastructure comprise of two or more independent cloud infrastructures (private, group or public) which remain specific units but are connected together by systemised or proprietary technology that allows data and portability of applications (e.g. cloud bursting for load balancing between cloud). [1]
Cloud computing is associated with complicated technology unlike a single piece of technology. It is a system mainly consisting of three services, software-as-a-service (SaaS), infrastructure-as-a-service (IaaS), and platform-as-a-service (PaaS). SaaS stands for Software-as-a-service and includes granting license of a software application to customers. The issuing of these licenses can be done through either model of pay-as-yougo or on-demand (e.g. Microsoft Office’s 365). IaaS stands for Infrastructure-as-aservice and this provides a technique for the services of storage and delivery between OS and servers using IP-based connectivity which is done as a part of an on-demand service. The benefit for clients is that they can acquire software or servers through outsourced, on demand service instead of buying those (e.g. IBM Cloud and Microsoft Azure). PaaS stands for Platform-as-a-service and it is known as the most complicated out of the three levels of cloud-based computing. PaaS is similar to some extent to SaaS, the main dissimilarity is that PaaS is a platform to design software supplied through internet (e.g. Force.com and Heroku) opposed to delivering software online. [2] People have many benefits by using cloud computing. Cloud-based software provides many different services with benefits for companies. It includes the ability to use software through a native app or a browse from any device. Consequently, users may move their files and settings to a different device without any trouble. Cloud computing not only provides accessing files on many devices. Rather than that, users are enabled to check their emails on any device and if needed users can store files (e.g. Dropbox and Google drive). Cloud computing services are useful for backing up files, important data, music files, and photographs as well. Those files and stuff are available when the hard drive gets crashed. Also cloud computing causes huge cost saving for the huge businesses. Before cloud computing become a good solution, companies required to purchase, build, maintain, high cost information management technology and infrastructure. But, after cloud computing became popular it enabled users to complete their tasks online easily. The cloud structure helps the users to save storage space on their computers. It also provides quicker updates through the products available via the web instead of the conventional, material methods like discs or flash drives (Adobe users can access applications in its Creative Suite through an Internet-based subscription. This provides the benefits of downloading new versions and fixes to their programs easily). Aside from all the benefits discussed above, cloud computing also has the fair share of its own risks. These risks mainly include cloud computing security issues. To increase the benefits of cloud computing, it is important identify the issues in cloud computing and to develop counter measures.
2. Evolution of the cloud security issues
Cloud computing is not a very new concept of technology. Cloud computing has developed step by step including Grid computing, Utility computing, Application Service Provision, and Software as a Service etc. Providing computing resource through a global network started in the sixties as concept. First the idea of the cloud computing concept by John McCarthy emerged around 1961. It was a brilliant idea but to activate the cloud-computing concept the technology was not ready. After some decades the idea of the cloud computing emerged in nineties. In 1999, Salesforce.com used a simple website to provide applications to users, in 2002, Amazon started to deliver many services through the Amazon web services, in 2009, computing enterprise applications were provided by Google Apps, and in 2009, Microsoft started the cloud services. As in the examples, cloud computing has become a mainstream in today world. Along with the development in the cloud computing the security issues also increased. There are many different types of security issues associated with the cloud computing. Those cloud security issues are not only affecting the cloud computing service providers. It also affects the cloud computing users as well. [3] The figure 2.1 below shows the increasing popularity of using cloud computing between 2008 and 2020, which makes it clear that usage of cloud computing is a rapidly growing trend.
Figure 2.1 Total size of the public cloud computing market from 2008 to 2020
Cloud computing services are very useful for users and the companies. Nowadays it is a very popular computing method all around the world. But, cloud computing has many security issues. There are five categories of cloud computing issues, namely, security policies, user-oriented security, data storage security, application security, and network security. Among these cloud security issues categories User-oriented security issues and The issues of data storage protection impact users more and more and are of greatest importance. This can be categorized in the following categories: data storage and computer protection problems, protection problems for virtualization, Internet and web security problems, network problems, problems with access control, software security issues, trustee management issues and enforcement concerns and legal aspects. [4] The following Figure 2.2 indicates that the highest-ranking issue among cloud computing concerns is issues concerning protection, which decide how security problems in cloud computing will be handled.
Figure 2.2 Rated issues on cloud / on demand model
Among the security issues regarding cloud computing, protection problems for virtualization and Data storage and computer protection problems can be considered most critical issues. Those managed to evolve with the advancement of cloud computing and are still present even with the modern technology. When the protection problems for virtualization is considered, virtualization can be known as the method which enables several Virtual Machines (guest machines) to operate on a solitary physical machine (host machine) and share the physical machine resources. This allows a single server to host a large number of guest virtual machines, operating system, and applications short of the added expense and complications arising from running such various physical machines separately. There are various ways for virtualization to take place. This could be application based, device based, virtualization of storage, virtualization of desktops, or virtualization of networks. It can also be hypervisor-based or non-hypervisor-based. Cloud computing is an extensible resource pooling framework with the aid of virtualization. Security is the biggest challenge any company faces during the conversion and deployment of their cloud infrastructure system. However, virtualization associated with many issues like issues with the guest, issues with the host OS, issues with the hypervisor, issues with the management interface, and issues with the networks. [5]
First is issues with the guest. There are two states that the guest image may exist in cloud infrastructure, either active or inactive. Although active guests have a broader area of attack, inactive guest images are still major security issues. The security vulnerabilities are not patching to inactive dormant virtual machines. One attacker can exploit these vulnerabilities and can gain control of the virtual machines. Although, the guest image has been inactive for some time, but it can still have confidential data like keys that could cause data breach. Active virtual machines have the entire attack surface, with some conventional virtualization technology issues, available for each physical computing process. An active virtual machine can be targeted from the internet, like every other physical device. Adjacent guest virtual machines can attack during cross-VM attacks, and because they share the same hardware it can have a more negative impact. Often, guest can benefit from the vulnerable situation to increase their privilege of controlling other virtual machines. [6] The second is Issues with the host OS. Every guest virtual machine run atop the host. However, if the host gets compromised, no guest part will be protected, so it is a very important job to protect the host. Nevertheless, securing the host is not so easy as the cloud service providers pay extra effort to harden the host, but there is always a risk of unfounded new security hole that can cause failure. An assailant using a Guest virtual machine will take advantage of vulnerabilities and increase their host control advantages, and if a host is controlled by an attacker, it may control all guest virtual machines above. Often, this kind of attack is called a host attack guest. Denial of Service attack is also a popular attack threatening the server to avoid responding to lawful requests by swamping bad requests. Local Denial of Service is used in the cloud network that certain virtual machine guests can do by grabbing all available resources and destroying all other virtual machines. Guest virtual machine can also use the unreported backdoor in the I/O system. It is known as information leakage, to access unprivileged details. And it can cause for malicious action by attacker. Along with local guest virtual machine, any other internet hacker may also aim the host operating system like every other physical computing device connected to the internet. [6]
The third is Issues with the Hypervisor. The hypervisor is software that acts as a manager of the virtual machine, lying between the virtual machines and the hardware. As it possesses the authority to control all the virtual machines operating on the physical network, damaging the hardware could cause notable harm to the entire cloud and cause significant harm to the entire cloud infrastructure. Virtual machine escape is a big attack on the hypervisor. In this hack, the attacker gets means to execute code to bypass the OS protection layer and begin to communicate straight with the hypervisor. In the cloud infrastructure, hypervisors gain a change at runtime at certain events to prevent downtime. Backdoor or rootkit can be introduced into the hypervisor during this change, and it can be used to manipulate the whole system. White box attacks are exceedingly rare cloud systems, but because of rogue system administrators and employees, those pose significant security issues because they can take advantage of their privileges to inject malicious below. [6]
The fourth is Issues with the Management Interface. The management interface is used in the cloud infrastructure to manipulate, maintain, and monitor guest virtual machines. As described above, the management interface location leans on the virtualization type utilized in the system. Guest virtual machines may jeopardize the management interface that can result in leakage of information and arbitrary code execution. Cloud systems where the web-based management interfaces are available to easily manipulate and display the virtual machines opens web-based attack surfaces. [6] The fifth is Issues with the Networks. Network virtualization operates well inside the cloud, so it provides many attack-surfaces in the cloud infrastructure. Virtual networks have different attack surfaces found on each software system (e.g. buffer overflow, integer overflow, etc.) which resulted because they are software-based. Compared to physical networks, software-based networks have less protection, so it is not hard to exploit and create network traffic that can cause major loss. Although several virtual defense solutions exist, traditional security issues still remain, such as the vulnerability of software-based systems. The networks can be threatened during virtual machine migration, which can cause data leakage and raise the question of the safety of the image of the virtual machine. There are several virtual networks that can be exploited by the entire cloud infrastructure and cause severe problems. As described above Virtualization issue is a very critical issue in cloud computing. It is a cloud infrastructure based issue. [6]
Data storage and computer protection problems. Data is an important aspect of cloud computing. Data stored in the cloud is secluded in an unreadable manner to the customers. Customers are unwilling to reveal the personal information or are always scared of losing the data, negative outcomes which may come up during controlling and processing. Therefore, the data must be unchanged during computation, restricted at every stage of processing and permanently stored for updating. The user does not know what happens to the data either in remote storage or in third party storage after storage in the cloud. The data owner is unaware of the cloud storage location, security infrastructure and cloud protection procedures. Quality of service is the essential aspect of cloud storage. A cloud storage provider requires proven methods and procedures to store data in the cloud efficiently and reliably. Safety and their solutions related to data storage, stable computing, availability of data and services, security mechanisms, cloud data recycling, and a variety of malware. To build a comfortable atmosphere, users need a system that saves data regularly, easily and safely in the cloud. [4]
Data storage. Losing control in the data storage is a significant problem in the cloud computing, because it does not have complete control of the data and is more difficult to verify originality of data and confidentiality. The cloud computer consumer is divided between data, servers and storage. A storage pool that can save data is provided by cloud computing. The server pool site is disclosed, and the provider of cloud service monitors and maintains it. The virtual level abstraction makes it difficult to locate the storage server’s real site. The user allows control to some extent only on the virtual machines. Data storage features such as multi-tenancy and virtualization give the attacker more opportunities to execute the hacking. Cloud data centers are used to store user data. Most major players have very low competitive cost of offering cloud storage. The circulated data is extremely excessive and is stored at various locations. The reliability of the electrical source and effective cooling secure the data is readily accessible. Cloud space can be reused efficiently with the aid of correct space allocation procedure. The data excessiveness supplies a procedure where data is backed up to another cloud server for to make sure that the data are easily accessible. If a data center is entirely ill functioning, backup data server can be used. In different countries Google and Amazon run various data centers. These companies store the data with a multi-placement feature. It also may trigger fresh security risks and legal issues, because worldwide stored data has different policies. [8] Stable computing. Most security service aim is to enforce the Software-as-a-Service application front end interface that comes at times the customer requests to web service or an HTML page. These applications may be changed or modified with behavioral pattern. When an application is called a specific application or service, a service tree can be created, the request is simply switched along the required services. Because of misconfiguration and malicious servers, a computing infrastructure that computes huge data sets in expanded system may produce the unexpected, wrong, and corrupt consequences. It is difficult to get and reliable and correct computing server. [8] Availabilities of data and services. The cloud’s physical and virtual resources are readily available. Structural modifications are needed in application and infrastructure level to achieve easy accessibility and adjustability of services and data. Running application that is alive with many servers can be one solution. But this causes Denial of service attack. Another problem with cloud computing is the availability of hardware. One fault may direct to fragmentary or total system break down, as a result of such system failure, impacting the quality of data and services. The lack of physical facilities will cause cloud unavailability that hamper the whole online work circle and trigger hazard. [9] Cryptography. The cloud information and data are secured using cryptographic mechanisms. It is a main idea for cloud security. It transforms the plain text data into another cipher text type. Poor application of the algorithm or the use of weak key encryption raises attack probability. For cryptography, the frequent attack is brute force attack, matching every feasible key for a known range with the encryption key. Another problem with passwords is that people build common words, such as their email passwords or the name of their partner. When easy to guess the security key data breaches can occur. Likewise, encryption issue is a huge problem in cloud computing. Cloud data recycling. It was a smart idea to reclaim the cloud space until the data was fully used and sent to disposal. However, it can be assured that the previous user’s data will not be available to the next customer. The procedure of cleansing or discarding data is called sanitization. Revived data are accessible to users like delivered way after sanitization. Data sanitization is an important activity in the distributed system to correctly dump of the data and pick the data that is given to the disposal. Data leakages and data loss may occur if the data are not properly sanitized. That is how cloud data recycling issue affected to the users. Data backup. Another critical thing in cloud computing is recovery of data from the cloud. A standard data backup process is required to ensure the data availability. This data backup process is conducted on the side of the service provider and allows data to recover in the an HTML page. These applications may be changed or modified with behavioral pattern. When an application is called a specific application or service, a service tree can be created, the request is simply switched along the required services. Because of misconfiguration and malicious servers, a computing infrastructure that computes huge data sets in expanded system may produce the unexpected, wrong, and corrupt consequences. It is difficult to get and reliable and correct computing server. [8] Availabilities of data and services. The cloud’s physical and virtual resources are readily available. Structural modifications are needed in application and infrastructure level to achieve easy accessibility and adjustability of services and data. Running application that is alive with many servers can be one solution. But this causes Denial of service attack. Another problem with cloud computing is the availability of hardware. One fault may direct to fragmentary or total system break down, as a result of such system failure, impacting the quality of data and services. The lack of physical facilities will cause cloud unavailability that hamper the whole online work circle and trigger hazard. [9] Cryptography. The cloud information and data are secured using cryptographic mechanisms. It is a main idea for cloud security. It transforms the plain text data into another cipher text type. Poor application of the algorithm or the use of weak key encryption raises attack probability. For cryptography, the frequent attack is brute force attack, matching every feasible key for a known range with the encryption key. Another problem with passwords is that people build common words, such as their email passwords or the name of their partner. When easy to guess the security key data breaches can occur. Likewise, encryption issue is a huge problem in cloud computing. Cloud data recycling. It was a smart idea to reclaim the cloud space until the data was fully used and sent to disposal. However, it can be assured that the previous user’s data will not be available to the next customer. The procedure of cleansing or discarding data is called sanitization. Revived data are accessible to users like delivered way after sanitization. Data sanitization is an important activity in the distributed system to correctly dump of the data and pick the data that is given to the disposal. Data leakages and data loss may occur if the data are not properly sanitized. That is how cloud data recycling issue affected to the users. Data backup. Another critical thing in cloud computing is recovery of data from the cloud. A standard data backup process is required to ensure the data availability. This data backup process is conducted on the side of the service provider and allows data to recover in the event of natural or unnatural hazards. Backup storage can be compromised by the frequent hackings such as unauthorized access and data tempering. So, people often find this form of threat to the data backup period. Data recovery. Cloud computing has functionality of resource pooling and elasticity. This component offers cloud capabilities for the requested user to manage dynamic and on demand resources. Since of this feature data recovery and confidentiality can be violated. It could be likely that the resources allocated to a requested user are transferred to someone else later. The hacker will use data recovery technique and locate the data from early users. It can cause many significant harms to the confidential user data.
Privacy and integrity. Though cloud computing has a computing network model that offers cost-effective and systematic infrastructure services. The task maintaining infrastructure does not have collaboration of users. This allows for the different security problems. That can direct to increased security risks in terms of data privacy and confidentiality in the cloud, the number of users and applications is growing. In the shared environment, malicious users collect user information which can breach the user’s privacy and integrity, but non-malicious users can also violate the data. Malware is very dangerous to cloud computers, since cloud data can be los or corrupted. Anti-virus agents are assigned to secure from those malwares. When the malware enters the network, antivirus agents must check the signature of the malware and if a coincidental match of signature occurs , but the possibility of a similar thing happening is rare, then the malware injects in to the network and it may remove the data, manipulate the data or do something with the data. If the anti-virus agent could not detect the malware it may cause very serious problems. Malware will spread to all files that are associated with the file to which it attached. As discussed above Data storage and computing security issue major problem affected to the users in cloud computing. [4]
3. Future developments in the area
When we focus on future development of cloud security issues, we mainly focus on two major sections. The two major sections are future development of cloud computing and future development of security issues in cloud computing. The first is Future development of cloud computing: Cloud computing’s market growth has assesed significantly to the rising carbon emission from ICTs, posing a concern about the energy-efficient and green existence of cloud computing. According to a prediction, carbon emissions are rising at a three times faster rate between 2002 and 2020, that currently amounts to 7.8 billion tons per year. Multiple studies indicate that cloud storage is a green technology, while there are several reports showing that cloud computing and data centers are contributing to significant co2 rises in the environment. Cloud framework has many features that render cloud computing much greener, but numerous technical efforts are still needed to make it possible. The first such effort is, Technology should be built at various levels (algorithm, compiler, OS and application) to improve system energy efficiency. Resources should be allocated to the application based on the necessary level of output in order to maximize energy versus consumption offs. The second is, to achieve green cloud computing, cloud providers need to consider and calculate existing data center capacity, server capacity usage, cooling requirements, and cooling designs in order to achieve maximum performance. Therefore, consumption of the energy of all the elements and resources of cloud computing software is calculated. The third is, all important factors such as network, memory cooling and CPU should be taken into accounts at the data center to design holistic resource scheduling solutions. The fourth is, it is the collective duty of both customers and suppliers to ensure that the changes triggered by the new technologies do not endanger the health of human society. Cloud companies need to deploy their data centers near renewable energy resources if they want to optimize the use of green energy. And the fifth is, cloud computing’s energy demands need to be reduced, as this cloud provider wants to take some essential measures to use renewable resources. In future development of cloud computing there are important trends like Quantum computing, Automation, and Open source development to get cloud computing to a better place. [10]
The second is Future development of security issues in cloud computing. As explained above in the paper we have various types of security concerns. In the future development of the security issues of cloud computing it need be reduced issues and more secure in the future. As mentioned earlier the virtualization issue and the data storage and computing security issues are the modern and critical issues in cloud computing. So, we must focus on the future development of those cloud issues. The first is protection problems for virtualization: First, for a good future development of virtualization in cloud computing should avoid from virtualization issues. For that, we must focus on some countermeasures. The first is Hardening the hypervisor and Virtual machine. Frequently, as explained earlier, hackers take advantages of error or vulnerabilities in the hypervisors, so it is necessary to strengthen the hypervisor. Proper firewall and antivirus configuration are necessary for the exposed terminals to prevent black box attacks. Hypervisor manage all the guest virtual machines, therefore it must be at top of the security management list of priorities. The second is secure programing. Cloud service providers and sellers must stick to safe programming methods and conduct tough trialing to prevent errors and vulnerabilities because this can result serious harm. The third is Securing the network. The protected network is necessary to evade leakage of information, execution of arbitrary code, redirection of network traffic and stability of virtual machines. Network should be protected using the secure communication channel such as SSL and IPsec. [6] The second issue is Data storage and computer protection problems. For the data storage future development, we need to avoid from the data storage issues: better security for resident data, File Assured Deletion scheme for data security, and using secure cloud protocol for secure storage are the better solutions for the cloud security issues. With almost half of the world now online and more users added each day as communications networks expand, it is fair that demand for the cloud storage will continue to grow. This means that more companies will be providing those services with new features in the future. [11] Future cloud storages will come up with these features. More trust, the risk of someone else using or losing the information has been shown to be largely unfounded enough times that trust between business and private individuals is rising. Data lost cost will be reduced, this means the data loss risk will reduce in the future development in the cloud storage. Data encryption and security will continue to improve, some of cloud storage’s main concerns is the hackers’ ability for accessing large quantities of information that can be used for unauthorized purposes. Although there is still a danger that a hacker might get around safety measures, programs have continued to reduce this danger. Better methods of encryption and protection features based on custom software designs mean data is safer than it is on home PC. Data storage providers retain staff experts who are constantly tracking networks and servers to ensure the protection and privacy of your files, and customized cloud storage. [12]
4. Conclusion
This report on cloud computing security issues mainly focuses on the objective of discussing the highest of critical, modern security issues in cloud computing. Cloud computing can be known as using a network of remote servers anchored on the internet to store, manage and process data, rather than a local server or a personal computer, according to the dictionary. Cloud computing has gained increasing popularity over time due to its many benefits. The way it offers software, infrastructure and platforms as services has helped to save a lot of expenses of using computer technology. Cloud computing also has many security issues as it provides space for storage of data of many users, and all the processes and other activities are conducted by a main host computer where the user cannot see or be certain of where the data has stored and processes are conducted. There are many such security issues regarding cloud computing. Some of those issues have managed to evolve along with the development of cloud computing making them very critical. The virtualization security issues, and data storage and computing security issues are selected in this report to discuss the evolution of the cloud computing issues as those were highlighted as the some of the modern and critical issues. Those issues are discussed thoroughly in this report. The future development of these cloud computing issues is discussed in this report paying special attention on counter measures as well. It is crucial to discuss the future development of cloud computing and the regarding security issues considering the increasing popularity it is gaining. It can be predicted that the near future will require a high level of cloud computing services. Addressing those issues and developing counter measures can contribute to the future development of cloud computing. Cloud computing may be considered as a huge part of present and future cyber space, which explains the significance of the study done in this report.
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