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SYSTEM SECURITY - Coggle Diagram

- - - - Ciphertext Attack Another name for a dictionary attack where a hacker has a list of possible passwords which are tried one at a time.
    - - A substitution cipher using a single alphabet. Eg: Caesar Cipher
        
        An example of ancient cryptography, said to have been used by Julius Caesar. A Caesar cipher is a mono-alphabetic substitution cipher in which the alphabet in the plain text is shifted by a fixed number.
      - Frequency analysis Block 2 part4 sec:1.1
        
        Frequency analysis is the study of the count and distribution of the letters in a text, typically the ciphertext. Analysing the frequencies helps in cryptanalysis for decrypting substitution-based ciphers.
      - A substitution cipher using a multiple substitution alphabets. Eg: Vigenère cipher
    - - The first known evidence of use of cryptography (in some form) dates back to an inscription carved around 1900 BC. Julius Caesar, around 100 BC, was known to use a form of substitution cipher to convey secret messages to his army generals posted at the battlefront; hence, it is often referred to as the ‘Caesar cipher’. The activity below explores the history of code-breaking and the origins of cryptography.
    - - The cryptographic system, you will recall, involves four components:
        
        Cryptographic system that uses cryptographic methods to secure a system or device.
        
        section 8.1 block 2 part4 A key space , or key space, is the set of all valid, possible, distinct keys of a cryptosystem. Simply put, it is the total number of possible values of keys in a cryptographic algorithm. For example, a 32-bit key would have a key space of 4,294,967,296.
      - 1,the plaintext
      - the algorithm (encryption, decryption, hash generation)
      - a key or salt
      - 4.the ciphertext.
      - ATTACK SURFACE
      - CRYPTANALYLIC An attack that uses cryptanalysis, that is, attempting to recover plaintext without the knowledge of the key used to produce the ciphertext, which the attacker has access to.An attack that uses cryptanalysis, that is, attempting to recover plaintext without the knowledge of the key used to produce the ciphertext, which the attacker has access to.
        
        Differential cryptanalysis attack involves using pairs of plaintext and corresponding ciphertext to derive a secret key that encrypted them. It uses a set of ciphertext and related plaintext that are encrypted with the same key and attempts to decipher the key.
        
        A differential and a linear attack used together.
        
        Cryptanalysis based on finding related approximations to the action of a cipher. The probabilistic linear relations (called linear approximations) between parity bits of the plaintext, the ciphertext, and the secret key are studied in the process of guessing the different bits of the secret key
        
        A parity check is the process that ensures accurate data transmission during communication. A parity bit is appended to the original data bits to create an even or odd number of bits of a value 0 or 1, typically, value 1.
    - - Salt is a unique, random string of characters known only to the process generating the hash of a plaintext such as a password. Typically, this ‘salt’ is placed in front of the plaintext or each password. The same salt has to be used when verifying the hash of an input string from the user, as in the case of a password, during authentication.
      - Salting is effective only if the salts are truly random and long enough.
    - - A cryptanalytic method that uses an exhaustive approach to recover a key. It attempts to use every possible key or password combination until one that works is found.
      - DoS (Denial of Service)An attack which consists of a high level of requests over a network which flood the target machine or network such it can not provide responses or fails entirely
    - - An attempt to break into a password protected system by systematically attempting entry using a list of well-known words or phrases. The attempt is exhaustive and the attacker could even try using all words in a dictionary, sometimes with additional characters added to the word.
    - - A rainbow attack or a rainbow table attack involves the use of a rainbow hash table to guess the passwords stored in a database system. A rainbow table is a precomputed table for caching the output of cryptographic hash functions, usually for cracking password hashes.
      - A rainbow attack or a rainbow table attack involves the use of a rainbow hash table to guess the passwords stored in a database system. A rainbow table is a precomputed table for caching the output of cryptographic hash functions, usually for cracking password hashes.
        
        BLOCK 2 PART 4 SEC 4
    - - COA The attacker can only monitor the encrypted communication and therefore has access only to ciphertext, but not the corresponding plaintexts.
      - KPA An attacker has access to the ciphertext and its corresponding plaintext. The objective is to guess the secret key or to engineer a cipher which would decrypt any ciphertext in that system.
      - CPA A scenario in which the attacker has the ability to choose plaintexts and to view their corresponding ciphertexts.
      - CCA A cryptanalyst gathers information by choosing a ciphertext and attempts to obtain its decryption. There is no knowledge of the key used for the decryption. This type of attack is applicable to public-key cryptosystems.
      - CKA A key is known in part or in full and the cryptanalyst attempts to understand the structural property of the cipher to be able to compromise the capability of the entire system that uses the cipher.
    - - Distinguishing algorithm Distinguishing the output of the encryption (ciphertext) from a random permutation of bits
      - Information deduction Gaining some information about plaintexts or ciphertext that was not previously known
      - Local deduction Discovering the original plaintext of a specific ciphertext
      - Global deduction Finding a functionally equivalent algorithm for encryption and decryption that does not require knowledge of the secret key
      - Total break Deducing and recovering the secret key
    - - ACTIVE
        
        , information is monitored, modified and re-introduced into the stored information or traffic between the communicating parties. Both the confidentiality and integrity of the information are lost. Typical examples of such attacks are masquerading, replay and repudiation.
      - PASSIVE
        
        information is accessed and monitored, but it is not modified – the integrity of the information remains while its confidentiality is lost. Such attacks are categorised under the interception attack vector (see ‘Interception’ in Block 2 Part 1).
        
        PROBING ATTACK(P.A) An invasive attack that directly accesses the internal wires and connections of a targeted device to extract/tap sensitive information. It is an invasive method to observe the physical silicon implementation of a chip or an on-board device.
        
        Side channel attacks(SCA) monitor patterns in the information exhaust that computers constantly give off as EMR – the electric emissions from a computer's monitor or hard drive. The emissions vary depending on what information is being processed, what is displayed on the screen or being read by the drive's magnetic head.
      - Reverse engineering attack involves analysing a hardware, software, or a hybrid implementation of a cryptographic algorithm, which is unknown to the attacker and to discover its function.
    - - PHYSICAL EVASION TACTIICS
        
        A non-invasive attack does not invade the device physically in any manner. Its objective is to collect as much information from being physically close to the device and manipulating the inputs to the device, such as power and clock signal, to see the variations in the output, if any.
        
        A semi-invasive attack limits the invasion to the packaging of the device and does not infiltrate it to access parts of the circuitry.
        
        An invasive attack requires physical manipulations of semiconductors. In comparison to non-invasive and semi-invasive attacks, this is the most powerful attack class, but also the most expensive (Skorobogatov, 2005). One well-known type of invasive attack is ‘micro-probing’. Micro-probing involves attaching microscopic needles to the internal wiring of a chip; these can be used to either extract internal secrets that are not intended to leave the chip or induce faults.
      - There are four types of implementation attack (see Figure 2.31): fault attack (FA), probing attack (PA), reverse engineering attack (REA) and side-channel attack (SCA).
        
        Induce faults in a cryptographic circuit, typically voltage, clock glitches, varying the temperature around the device, vibration, infrared light, and wrong input data so that it behaves abnormally and/or delivers incorrect results. These results could reveal some information about the secret key.
    - - BIRTHDAY ATTACK A type of cryptographic attack, which exploits the mathematics behind the birthday problem in probability theory. The birthday problem, also known as the Birthday Paradox, states that in a random group of 23 people, there is about a 50 percent chance that two people have the same birthday.
      - Meet-in-the-middle is a known plaintext attack that can greatly reduce the number of brute-force permutations required to decrypt text that has been encrypted by more than one key. This attack targets the cryptographic function and brute force technique is applied to both plaintext and ciphertext block.
      - REPLAY ATTACK An attack on a communication session in which an intruder repeats or replays a message that they had previously recorded (but not necessarily understood).
      - RELATED-KEY ATTACK
        
        Any form of cryptanalysis where the attacker can observe the operation of a cipher under several different keys whose values are initially unknown, but where some mathematical relationship connecting the keys is known to the attacker.
      - KDF A key derivation function is used to generate one or more cryptographic keys from a private (secret) input value.
      - Rubber hose attack is extracting secrets from people by use of torture or coercion. Other means are governmental and corporate influence over other sub-entities.
  - - - D.E.S.
        
        A symmetric block cipher with a key length of 112 or 168 bits. An extension of the original Digital Encryption Standard (DES).
      - A symmetric block cipher with a key length of 546 bits. This is no longer used (deprecated).
        
        R.S.A
        
        An asymmetric encryption method named after its three inventors: Ronald Rivest, Adi Shamir and Leonard Adleman.
        
        A method for generating a hash – now deprecated (out of date).
      - TRIPLE DES or 3DES.
        
        D.E.S , which used a relatively short 56-bit key. Fifty-six bits encodes any number between 0 and 256 (which is approximately 72,057,594,040,000,000 or 7.206 x 10 16 or 72 quadrillion). The first successful Brute-Force Attack (BFA) on DES was reported in 1997 (Curtin and Dolske, 1998), with the cipher being completely withdrawn as a US Federal standard some years later.
        
        3 Digital Encryption Standard (3DES) by comparison has a key length of either 112 or 168 bits depending on which version is used, and is consequently more secure. There are three options for implementation:
        
        Option 1 (168 bit) uses three different 56-bit DES keys to repeatedly encrypt data. This is considered the most secure form of 3DES.
        
        Option 2 (112 bit) uses two 56-bit DES keys. Three rounds of encryption are performed using the first key, then the second key and then the first key again.
        
        Option 3 (56 bit) is a single 56-bit DES key that is used to perform three rounds of encryption. The end result is the same as applying DES encryption to the data. Option 3 was included in the 3DES specification purely for compatibility purposes with systems implementing DES that could not use larger keys.
    - - A block cipher divides the plaintext into fixed lengths of bits; examples are 3DES and AES.
      - A stream cipher encrypts one bit or one byte at a time. Stream ciphers are faster than block ciphers and, in general, more efficient for streaming video or audio; examples are Rivest Cipher 4 (RC4) and Software-optimised Encryption Algorithm (SEAL).
      - Initialisation vector iv A value required in the generation of a block or stream cipher. This value should not be easily predicted.
      - NONCE An arbitrary mathematical value which is used in various cryptographical algorithms.
        
        An arbitrary mathematical value which is used in various cryptographical algorithms.
  - - - Non-repudiation can be provided through the careful use of different encryption algorithms, together with digital signatures and certificates, as you will see later. Non-repudiation can be applied both to the sender of a message (so that they can’t deny that they sent it) and also to the receiver (so that they can’t deny that they have received it) – like signing for a parcel on delivery.
    - - DIGITAL SIGNATURE A method of authenticating the authorship of a message.
      - DIGITAL CERTIFICATE Proof of ownership of a public key.
        
        PUBLIC KEYS A person’s public key in an asymmetrical cryptography system is available to anyone. It is related to the person’s private key but neither can be easily derived from the other.
        
        Certificate authority
        A trusted institution who will authenticate the ownership of a public key.
        
        Public Key Infrastructure (PKI)
        A system whereby public keys can be authenticated and distributed by a trusted institution.
  - - - Plaintext is unencrypted information that can be read directly by humans or a machine (this study material is an example of plaintext). Plaintext is a historical term, pre-dating computers, when encryption was used only for hard-copy text; nowadays it is associated with many formats, including music, movies and computer programs.
      - Ciphertext is encrypted information.
      - A cipher or cryptographic algorithm is the mathematics responsible for turning plaintext into ciphertext and reverting ciphertext to plaintext (you might also see the word ‘code’ used – there is a technical difference between the two but it need not concern us now).
      - Encryption is the process of converting plaintext to ciphertext (occasionally you may see it called ‘encipherment’).
      - Decryption is the process of reverting ciphertext to plaintext (occasionally referred to as ‘decipherment’).
      - A cryptographic key is a value that is used to control the output from an encryption (or decryption) process for a given plaintext. A key is a string of bits and is of a specific size, depending on the cipher.
      - An encryption key is a type of cryptographic key and is a piece of information used in combination with an algorithm (a ‘cipher’) to transform plaintext into ciphertext. (A decryption key would be used to reverse the process.)
      - Symmetric cryptography is a cryptographic scheme in which both the encryption and decryption processes use the same cryptographic key.
      - Asymmetric cryptography is a cryptographic scheme in which the encryption and decryption processes use different cryptographic keys.
  - - - The Blowfish system was designed by Bruce Schneier in 1993 and uses a 64-bit block size with a variable-length key (up to 256 bits). Another system, Twofish, is derived from it. Twofish has a larger, 128-bit block size.
  - - - The Heartbleed Bug is a serious vulnerability in the popular OpenSSL cryptographic software library. This vulnerability enables compromise of information encrypted by the SSL/TLS encryption algorithm that is used to secure the Internet.
  - - - A system used to protect data on a virtual private network.
        
        Tunnel information phases =HAGLE
        
        H – hashing algorithm
        
        A – authentication method
        
        G – groups (which Diffie–Hellman group to use)
        
        L – lifetime
        
        E – encryption method
    - - A secure connection between two devices over a network in which the IP address is hidden and the data is encrypted.
    - - AH Information added to an IP packet to provide a means to check for data integrity and data.
      - SPI Part of the Authentication Header (AH) or Encapsulating Security Payload (ESP) this contains information about security associations.
      - ESP Like Authentication Header (AH) this provides data origin authentication, integrity, and an anti-replay service. In addition, it provides confidentiality in the form of encryption. The integrity protection is optional. Unlike AH, ESP only provides authentication for the payload.
        
        ESP encryption protocols include AES and 3DES.
  - - - The first part of the digital envelope is
        {X, n, Bf, {H(n, Bf)}KF(pr)}Ke
- - - - DISADVANTAGES OF MAC
        
        These issues make pure MAC systems complex to develop and maintain, which is reflected in their high administration and maintenance costs.
    - - ADVANTAGES
        
        Rather than requiring administrators to configure permissions for individual users, RBAC allows organisations to create a single set of transactions for all users in a role. Users are automatically assigned the correct transactions as soon as they assume a role. If the role itself evolves, every user in the role automatically has access to the most up-to-date transactions.
        
        RBAC also avoids potential security risks caused by users retaining permissions after leaving a role. Under RBAC, as a user moves between roles, they automatically lose permissions associated with the transactions from their old role and receive a new set of permissions for their new role.
        
        Under RBAC it is not possible to grant a user permission outside of a role. Users cannot receive additional (potentially dangerous) permissions without the creation of a new role – a process that should be strictly controlled and documented.
      - DISADVANTAGES There are some disadvantages of RBAC. Perhaps the most significant is the expense of identifying roles and transactions within an organisation. For small organisations, the processes of identifying, creating and maintaining roles is likely to be more labour-intensive than assigning individual permissions under DAC.
        A second disadvantage is known as ‘role explosion’, where, in order to give fine-grained access controls to users working on slightly different tasks, administrators create an ever-larger number of roles. Left unchecked, role explosion may even result in every user being allocated to a different role – effectively removing one of the advantages of RBAC over DAC! Where role explosion is likely, it may be necessary to abandon strict RBAC and create a smaller number of roles whose users have access to transactions not needed for their specific role within the organisation. This obviously creates a new security risk but reduces the complexity of administering roles themselves.
  - - - In a DAC system, objects are associated with so-called permissions:
      - read (often abbreviated to r) allows you to open a file, but not to make changes
      - write (often abbreviated to w) allows you to make changes to a file
      - execute (often abbreviated to x) allows you to run a program.
    - - ACLs have the advantage of being relatively simple to describe and implement, which perhaps explains their longevity. They are especially well-suited to computer systems where users are responsible for their own security and share little data with other users. They also work well on computer systems with a small number of long-term users.
      - DISADVANTAGES OF DAC
        
        An ACL cannot, on its own, keep track of which resources have been used by individual users.
        
        ACLs can be cumbersome to modify in systems where there are a large number of users or where new users are constantly joining and old users are leaving.
        
        DAC is not well-suited to situations in which a user needs access to a resource for a limited period of time, after which they must be excluded. It is possible to give people new permissions, but it is then necessary to remove those permissions or risk a breach in security. An example might be where a user joins a team for a short period of time to complete a task before returning to their original role. Role-Based Access Control (RBAC), discussed next, is one solution to this issue.
        
        Checking that every user and every resource in a computer system always has the correct permissions is a complex and time-consuming task, even on small systems – a modern PC may have several million files on the disk before it is even used for the first time!
  - - - Step 1: A subject makes an access request, which is intercepted by the Policy Enforcement Point (PEP).
      - Step 2: The PEP forwards this request to a context handler, which is responsible for determining how any applicable authorisation policies should be used to make an access control decision.
      - Step 3: The context handler sends the request to the Policy Decision Point (PDP) (3a), which determines which policies apply (3b) and which associated contextual attribute values are needed to evaluate these policies.
      - Steps 4–5: The PDP requests the attribute values from the context handler, which in turn sends a request to the Policy Information Point (PIP) to retrieve the attribute values. The PIP queries the subjects, resources and environment to evaluate the attributes and returns these values via the context handler to the PDP.
      - Step 6: The PDP responds to the context handler, based on the evaluation of the authorisation policies. This response includes both the access control decision and any obligations that need to be enforced.
      - Step 7: The context handler forwards this response to the PEP, which enforces the access control decision and permits or rejects access to the system resource.
  - - - Understanding high-level principles of security control and server hardening is important as these are applicable across different systems and organisational contexts as well as having some longevity. While the specific details of how to establish security – for example, using Windows Defender to scan – will change, the more general principle of periodic scanning or checking the integrity of a system will remain as good practice for some time.
      - CYBOK
      - Read the paper
      - NIST
      - Sometimes taken as synonymous with server hardening but often take to be encompassing further components such as networking, routers, backup devices, etc.
      - SERVER HARDENING ACTIVITIES BLOCK 2 PART 6 SEC 4.2
        
        USING LINUX COMMANDS MAN
  - - - How does yum work?
        Yum works by keeping track of what is installed and maintaining a list of software repositories on the internet, known as ‘repos’. When yum is used to update or install software it checks the list of installed packages and their versions against those in the repos. If a package is not up to date it is listed as a candidate for replacement.
        
        YUM PERFORMS A RANGE OF SERVICES.
        
        maintaining a list of the software and versions installed on the system
        
        enabling new software to be installed
        
        enabling installed software to be deleted
        
        upgrading application and system software
        
        maintaining a list of repos.
        
        To use yum to determine what updates would be relevant to security, enter:
        
        yum –security check-update
        
        To perform the update, enter:
        
        yum –security update
        
        yum repolist
        
        rpm -Uvh <repo>
        
        yum-config-manager --add-repo <repo_url>
        
        To check if any part of the OS is out of date, enter:
        sudo yum check-update
        
        sudo yum update
        
        sudo yum upgrade
        
        The yum update process has a set of 5 stages:
        
        Using the local list of packages, compare the versions installed to those available in the known repos on the internet.
        
        Confirm with the user that the packages listed should be updated.
        
        Install the updates. This can take quite some time.
        
        Verify that the changed packages are complete – as there is usually a range of dependencies between packages – and working.
        
        Produce a brief report of the updates.
    - - The default most privileged user account with access to all resources including all user accounts, files and configuration settings.
        
        Activity 2.33
        
        Netalabs #8
        
        Activity 2.34
        
        Netalabs #9
    - - Activity [2.36] Netalabs #12 (https://learn2.open.ac.uk/mod/oucontent/olink.php?id=2064617&targetdoc=NetLabs+resources)
        
        CREATING A PASSWORD POLICY Windows has a security approach based on ‘Group Policy Objects’. Group policies control the operations of accounts, applications and Windows itself. As you have seen in Linux, it is usual to establish a password policy. Now you can see how to do this in Windows. So, in this task, you will create new group policies to specify password rules.
        
        Activity 2.38 Netalabs #13
      - Blocking ports
        
        Activity 2.37
    - - Activity 2.39 Link Title
  - - - Sometimes equated with BIOS but sometimes thought of as the hardware read-only memory that holds BIOS to boot a machine. There are also firmware instances such as in network and video cards. There are other types of programme which are stored in firmware for other types of device.
      - BASIC INPUT AND OUTPUT SYSTEM
        
        The basic input and output system is the program used to start the system up and load the operating system (OS) when it is powered on. It also manages the connections between the OS and attached devices.
      - UNIFIED EXTENSIBLE FIRMWARE INTERFACE (UEFI)
        
        Similar to Basic Input-Output System (BIOS) but with extended capabilities where initialisation information is stored in a file such that it can be updated more easily, larger discs can be supported and booting is faster and more secure.
      - MBR
        
        A Master Boot Record (MBR) consists of a program and information stored on the first sector of a main hard disk that identifies how and where the operating system is located so that it can be loaded into the computer's memory. It also includes information about disc partitions.
        
        This code loads the OS kernel and then control passes to the OS.
        
        bios protection guidelines
        
        READ Activity 2.40
- - - - AUTHORISATION RULES
        
        subject: entity attempting an operation on an asset
        
        object: the asset on which the operation is being performed
        
        action: the operation that the subject is attempting to perform on the object
        
        permission: whether the request to perform the operation is allowed or denied.
        
        Mandatory Access Control (MAC)
        
        Discretionary Access Control (DAC)
        
        Role-Based Access Control (RBAC).
  - - - Two common approaches to 2FA are shown in Figure 2.40. The first stage of each approach is commonly a username and password but the second stage differs. In the left-hand screenshot, the user is asked to supply a small number of characters from a second password or from a series of digits the user knows. In the right-hand screenshot, the user is asked to supply a one-time password, which is sent to the user via another channel, such as their mobile phone.
  - - - Any process for identifying usage of system resources.
      - The functional process of a system that enables tracing a set of actions on a system, of an entity (typically a user of the system), uniquely to that specific entity. Such processes are part of the operating systems functions in a computer system.
      - This is sometimes called accounting.
  - - - The data collection components of an accountability mechanism record the information needed to answer the questions posed by the accountability requirements. Data could be collected by different components of the system independently, with some coordination of these data collection tasks where needed.
    - - GrayLog: a log management tool that provides a centralised store of system logs that different components can feed into. It allows administrators to create customised dashboards to visualise security event data generated by a system. It is highly scalable, with the ability to manage large volumes of log data.
      - Nagios: another tool capable of building centralised logs and providing search capabilities for extracting useful insights from the logs.
      - LOGalyze: provides log consolidation and analysis capabilities, collecting data from multiple servers, applications and network devices. It also provides tools to perform automated analysis to check if a system is compliant with regulations such as those associated with the Health Information Portability and Accountability Act (HIPAA) in the US.
      - ELK: derives its name from a combination of tools – Elasticsearch, Logstash and Kibana, each of which provides different capabilities to support the log management and accountability needs of a system. Logstash collects log data, Elasticsearch provides a high-performance search capability across large collections of log data and Kibana provides tools for extracting and visualising log data for different purposes.
- - - - CONTEXT OF INFORMATION SECURITY
        
        Assets are tangible/intangible things of value: Value could imply its cash value or its importance as a system function. A system is an asset, as is the data, software and hardware that comprise the system.
        
        Assets are targeted by threats: A threat could be the threat of theft or the threat of impeding, distorting or stopping a system or a system function. The estimated threat-level differs based on the context. For example, the threat of theft is high in urban areas and low in rural areas, and the threat of theft is high for the computer system peripherals compared to theft of computer internals such as the hard-disk.
        
        Assets could be attacked by exploiting a vulnerability: If they are not protected (secured), they will succumb to it. For example, if the peripherals are not secured physically, they can be stolen or misplaced; if applications are not written with security in mind, they can be manipulated to malfunction. An exploit is an unauthorised access to an asset that is part of the system.
        
        Assets could contain a vulnerability: Attackers will ‘exploit’ the vulnerability, if there is one. In the context of software and applications, the vulnerabilities are often unnoticed programming or logic errors that are exploited by malicious attackers whose intent is to impede, distort or stop a function of the system.
        
        A security mechanism responds to an attack: The security mechanisms help the system to ensure that its security objectives are achieved by taking steps that will respond to an attack. For example, at the application layer, a multi-factor authentication mechanism helps the system to
- - - - replay attack in which malicious third parties intercept communications and retransmit them in an attempt to impersonate a legitimate user.
- - - - ISO/IEC 27002 Code of controls for information security controls
      - ISO/IEC 27003 ISMS implementation guidelines
      - ISO/IEC 27004 Monitoring, measurement, analysis and evaluation of information security management
      - ISO/IEC 27005 Information security risk management
      - ISO/IEC 27006 Guidelines for audit and certification of ISMS (accreditation agencies)
      - ISO/IEC 27007 Guidelines for ISMS audits
      - ISO/IEC 27008 Guidelines for auditors on information security controls
      - ISO/IEC 27001 Requirements of ISMS
    - - Implementing ISO 27001 helps businesses to:
      - improve risk management
      - provide a normalised interoperability between organisations, or groups within organisations
      - demonstrate good security practices resulting in a competitive advantage
      - win business with companies in regulated sectors
      - fulfil regulatory compliance (GDPR) and pre-requisites for large contracts
      - establish market reputation for secure practices
      - avoid financial losses and regulatory penalties arising from security breaches.
- - - - A simple operating system architecture which places all elements (hardware access, applications etc) within a single trust environment such that once authorised a user has unrestricted access.
      - TRUST BOUNDARIES
        
        A security measure which limits access to some system component, hardware or software, to those who can authorise for such access.
    - - This operating system model separates breaks the system down into several trust zones, a central kernel and user applications which are managed by the kernel.
    - - This operating system model breaks the system down into components such as applications, file store, networking, drivers, etc and provides each with a trust boundary, connected using inter-process communication and accessed with authentication.
    - - A cloud technology term used to denote a single user account or project account which is managed by the hypervisor which insures appropriate use of resources and that the account is kept secure and isolated from others.