Domain 3 Flashcards
1
Q
____ have the concept of the user owns the file. E.g., windows, you own the file, you own the spreadsheet. When you own it, you can change permissions of the file and of the data (send it to someone, etc.)
A
Discretionary access control (DAC)
2
Q
____ is a system enforced access control based on a subjects clearance and an objects labels. Users of files cannot change attributes of the files
A
Mandatory access control (MAC)
Subjects (person) have clearances and objects (file or piece of paper) have labels such as secret, top secret, etc.
Subjects cannot share objects with other subjects who lack proper clearance, or “write down” objects to lower classification level
Rule read down and write up only; no read-up
An example of MAC is Bell-La-Padula
This is expensive and difficult to implement
Focused on CONFIDENTIALITY
3
Q
The modes of operation (types of subjects and objects) contained in a MAC system are:
A
Total of 4 modes that should consider least privilege and need to know:
1) Dedicated - system contains objects of one classification label only (e.g., secret only). All subjects must possess clearance equal to or greater than the label of the objects
2) System High - system contains objects of mixed labels (e.g., confidential and secret). All subjects must possess clearance equal to the systems highest object label.
3) Compartmented - Objects are placed into “compartments” and require a formal need to know to access (which is system enforced). All subjects have the necessary clearance and a need to know for certain information only.
4) Multilevel - stores objects of differing sensitivity labels and allows system access by subjects with differing clearances.
4
Q
Bell-La-Padula (BLP) is:
A
A security model that is a mandatory access control and focuses on CONFIDENTIALITY and does NOT address integrity
Data flows UP
- Simple security property: no read up
Star - Property (star property): no write down
- Strong * Property (strong star property) - no read down and no write up - stuck in the middle
5
Q
BIBA is:
A
A security model that is focused on INTEGRITY
- Simple integrity property - user cannot read data to a lower integrity level
- Integrity star property - a user cannot write data of a higher integrity level
Rules with the word integrity is related to BIBA
Data flows down from most trusted to less trusted
6
Q
A lattice model is:
A
A model that requires that every subject and every object be labeled with one of a number of security designations. Access is granted based on the comparison of those labels; a user of a certain designation can only access resources of the same designation or lower.
Lattices allow further granularity in granting access, allowing technical enforcement of compartments.
Lattice deals with confidentiality
7
Q
Clark-Wilson model is:
A
A security model that deals with integrity and is the “real world” application of BIBA
Authorized users cannot make unauthorized changes and unauthorized users cannot make changes.
Ensures both internal and external consistency (which means you have integrity internal (database) and external (physical count) - database number matches reality)
Does all this through
1) well-formed transactions - think about all the steps that are logged when you order an ipad (order is logged, ipad is scanned, shipping label is created, etc.)
2) separation of duties.
You must access objects via programs. These programs have specific limitations which limits the capabilities of the subject.
TIP - the hyphen in clark-wilson reminds us of separation of duties
8
Q
State Machine is:
A
A mathematical security model. Like a lattice - different but its math. Enumerate all the states of the system (top secret, confidential, etc.). Verify no read-up is always true. Simulate every action a user can take on a system and all the states and afterwards check if anyone ever read up. If we enumerate all the states, and secret never read up, the system is secure.
9
Q
A research model is:
A
Used to research the best security posture possible for automated information systems.
Noninterference: you cannot infer something is going on in the system. high level actions do not determine low level user visibility. Think the pentagon pizza story
Information flow: similar to BLP, objects are labeled based on security classes in the form of a lattice. Information objects represented can flow in either direction
10
Q
Chinese wall model (aka Brewer Nash) is:
A
Made to deal with conflict of interest. No information flow is allowed that could cause information leakage that could lead to a conflict of interest
COI (conflict of interest) groups is the answer on the exam - conflict of interest-
11
Q
____ consists of the security-relevant parts of a system that include: access control mechanism, reference monitor, the kernel and protective mechanisms.
A
Trusted Computing Base (TCB)
For terms of analysis, assume that the components are properly implemented and secure. Assume the TCB is secure
12
Q
The ____ mediates subjects access to objects and is responsible for enforcement of system security policies
A
Reference monitor
This is always enabled and cannot be bypassed.
Runs in ring 0
must ensure it is doing its job
13
Q
Domain / Object domain in the context of security models is:
A
A set of objects that have the same security requirements (e.g., top secret, kernel, ring 0, confidential, etc.).
Ways to separate domains can be through:
- Execution rings
- Base address registers
- Segmentation descriptors
14
Q
What are three security evaluation models
A
1) Orange Book (Trusted computer security evaluation criteria - TCSEC)
2) ITSEC (international attempt)
3) The common criteria and ISO 27002
15
Q
What are the main components of the Trusted Computer Security Evaluation Criteria (TCSEC) Orange Book?
A
This is part of the rainbow series and it covers operating systems, applications and computer related products which are classified into one of four categories / classes to describe their key principles which are 1) functionality (how well it operates), 2) effectiveness (how secure is it) and 3) assurance (can we verify and prove its secure).
The classes are:
A - Verified Protection (everything B is and more - MAC+)
B - Mandatory Protection (MAC)
C - Discretionary Protection (DAC systems)
D - Minimal Protection ( this is nothing - laptop in front of you)
Maybe 1-2 questions in the exam but focus on ABCD and then common criteria instead
16
Q
ITSEC is:
A
First international attempt at a similar function as the orange book.
Target of evaluation - system you are evaluating
Functionality - how well is the system operating
Effectiveness - how secure is it
Dont spend too much time on this for the exam - focus on common criteria
F1 - F10:
- F1 is least assurance level and F10 is the most - can play the high low game on the exam. 10 is the best, 1 is the lowest
Assurance Levels:
- F1 - F5 = mirror functionality of the orange book
- F6 - high integrity requirements
- F7 - high availability
- F8 - high integrity for communication
- F9 - high confidentiality
- F10 - high confidentiality and integrity for data networks
17
Q
The common criteria is:
A
A security evaluation model that is created by ISO and an international attempt. It has 7 evaluation assurance levels (EAL) that go lowest to highest)
EAL 1 - functionally tested
EAL 2 - structurally tested
EAL 3 - methodically tested and checked
EAL 4 - methodically tested and checked
EAL 5 - semi-formally designed and tested
EAL 6 - Semi-formally verified, designed and tested
EAL 7 - Formally verified, designed and tested
Terms:
- Target of evaluation - TOE - the system or product that is being evaluated
- Security Target - ST - the documentation describing the TOE, including the security requirements and operational environment
- Protection profile (PP) - an independent set of security requirements and objectives for a specific category of products or systems (firewalls, IDS)
- Evaluation assurance level - evaluation score of the tested product or system
18
Q
The computer bus links which devices
A
CPU, RAM and disk with the network, DVD, keyboard/mouse and display
19
Q
___ is the brains of the computer and contains specialized regions that perform different functions. It is composed of at least two parts:
A
the CPU which is composed of at least 2 parts:
1) The control unit - coordinates system activities during execution of code. manages the flow of execution in a program and decides which instructions to process next, fetching them from memory, executing them and storing the results. During execution, the control unit call supon the ALU
2) the arithmetic log unit (ALU) - data transfer operations, arithmetic operations, data editing and decision making. performs whatever arithmetic and logical operations the program calls for - crunches numbers and adds
Registers - primary storage memory unit - stores instructions and data for current programs in use - holds data
20
Q
The fetch-decode-execute cycle is:
A
Sometimes known as the fetch and execute cycle but is three phases - fetch, decode and execute.
Fetch decode without pipeline and with pipeline
- fetch = get the instruction (add these two numbers)
- decode = I understand the instruction - what you want me to do (ok I know what you want and I will add the two numbers
- execute = do the instruction (add the two numbers)
- store = save in register after execution and move on (get the result of the two added numbers) - considered part of the execution phase
pipeline loads something up and does multiple things at the same time - it becomes 4x faster
pipeline is CPU and is a hardware thing
21
Q
What are the 2 basic types of instruction sets (CPU design):
A
An instruction set is a set of low-level instructions a CPU knows how to execute.
1) Complex-instruction-set-computer (CISC) - performs many operations per instruction and a wide variety of instructions - offers programmers a lot of flexibility with relatively little effort - X86
- this is one longer command
- most laptops and desktops are CISC
2) Reduced-instruction-set-computer (RISC) - simpler instructions using fewer cycles - pare things down to their basics and concentrate on making a small instruction set as efficient as possible. This boosts performance, but places more burden on the programmer. - ARM
- this is multiple commands
- most cell phones are RISC
Interrupt - stop the CPU from doing what it inteded to do and interrupt CPU execution
22
Q
1) ____ executes multiple tasks concurrently on ONE CPU and is also a heavy weight process (HWP)
2) ____ allows multiple threads concurrently on on CPU and is also a light weight process (LWP)
3) ____ executes multiple tasks concurrently on multiple CPUs
A
1) Multi-tasking: can process more than one user program at the same time on one CPU. A task is a heavy weight process where each process has its own copy of memory. all load their own copy of something. Processes do not share anything
2) Multithreading: light weight process where each thread uses shared memory for shared libraries (save RAM) - you point to a shared process. threads share RAM and memory
3) Multiprocessing: the computer has more than one CPU and it can execute instructions in parallel
- — Symmetrical multiprocessing system - they support more than on processor and CPUs share the processing of system processes equally
- — Asymmetrical Multiprocessing systems - one processor will take care of the system processes and other processors will run the applications
23
Q
Memory protection techniques:
1) ____ Prevents one process from affecting the confidentiality, integrity, or availability of another
2) ____ randomizes addresses used by programs, which makes jumping code injected via buffer overflows more difficult
3) ____ marks pages of the stack non-executable
A
1) Process isolation and is a memory protection technique - I cannot read you memory
2) Address space Layout Randomization (ASLR): random addresses used by program. previously, memory locations were highly predictable, allowing an attacker to predict where their injected shellcode would be placed in memory and allowing them to jump it and execute.
3) Non eXecutable stack: e.g., Linux NX, Microsoft data execution prevention (DEP) - you can write but you cannot execute - its an XOR - or you can execute but you cannot write
24
Q
What is virtual memory?
A
Virtual memory is a set of memory addresses managed by the OS that doesn’t correspond directly to physical memory. To the CPU, virtual memory looks like physical memory. It can hold both programs and data, but gives the OS the choice of where to store the data.
Virtual memory maps the virtual address space into the chosen physical address space. When the system needs to access a memory address, the OS can translate the virtual address into a physical one and fetch the data from the correct location. Because virtual memory hides the actual storage location from the hardware, the OS is free to store the data wherever it likes, including a mass storage device, such as a hard drive. This lets the system address a larger amount of memory than it actually contains. The OS uses the main memory as a cache to hold the most recently or most frequently accessed data, whereas the rest of the data is stored on the hard drive or the disk.
threads also use virtual addresses
25
What is Paging and Page Fault?
Paging occurs when the OS copies virtual memory from disk to main memory or vice-versa.
Page fault is an exception that results in paging - it is when the process realizes the data is in disk and needs to be called to main memory to be used which prompts paging - e.g., you dont use a word document for a while. when you go to open it you notice it takes a second or two to load - this is because the document went to disk and is being called back to main memory. There was a page fault which prompted paging to occur
Swaps are similar to paging but swap is one big swap all at once
Locked memory prevents data from being paged
26
What is memory addressing?
The theoretical ability to store and retrieve data in memory is useless without the ability to tell the memory system where to store or fetch the data. Each byte in memory is assigned a unique address that distinguishes it from the other bytes.
27
What are the ways a CPU can address memory?
1) Direct addressing - simplest form of addressing. The system knows the exact location of data in memory and requests the data by passing the actual address to the memory subsystem
2) Indirect addressing - The first location contains an address (a pointer) to another location that holds the data
3) Register direct addressing - the CPU contains tiny memory areas known as registers. Registers are temporary storage for the task the CPU works on at that instant. To operate on values from main memory, the values must first be loaded into a register. Register direct addressing is slightly different from the other types of addressing in that it never refers to main memory. It simply refers to a specific register that already contains the required data
4) Register indirect addressing - In this addressing mode, the system looks in the specified register for the data's address in main memory
5) Indexed addressing - Uses a memory location, plus an offset (called an index register). For example, the address may contain an array and the index register references an element of the array (go here plus this)
28
What is the operating system?
The OS is the heart of the computer and is loaded by a boot program. It controls everything that happens with the hardware and brings the hardware to life
The mainframe boot process is called Initial Program Load (IPL)
The OS does:
1) program execution
2) system access
3) error detection
4) accounting
Process States are:
1) run
2) wait
3) ready
4) sleep
5) interrupt
29
What are the OS states?
1) User - layer in the operating system where user applications run
2) Privileged - protected area of the operating system (or kernel) responsible for memory, process, disk and task management.
30
What is the kernel of the OS?
The kernel is the essential nucleus of the OS, the core that provides basic services for all other parts. A kernel can be contrasted with a shell, the outermost part of an OS that interacts with user commands. Typically, a kernel includes an interrupt handler that handles all requests that compete for the kernels' services, a scheduler that determines which programs share the kernel's processing time in what order, a virtual memory manager, and a supervisor that gives use of the computer to each process when it is scheduled.
Applications can request kernel service through system calls. When the kernel is executing on a CPU, the system is operating in privileged mode. This means it can interface directly with other parts of the OS and view all the internal data structures.
When user applications run in user mode, they rely on the system call interface to request services from the kernel.
Because the code that makes up the kernel is needed continuously, it is loaded into protected memory so that it will not be overlaid with other less frequently used parts of the OS. In a VM system, the kernel would never be swapped out to the disk and would remain in physical RAM at all times.
31
How can you protect you OS? What are the mechanisms?
1) Layering - organization of functions into separate components, each of which interacts with the others in a sequential way. Each layer will interface only with the layer above it and the layer below it and should work independently. If one layer in the system fails, it should not affect the other layers.
2) Abstraction - the process of finding commonality in different objects, and then exploiting it to make the objects simpler to manage. The ultimate goal is to reduce complexity and to hide the inner workings of the system. A good example of this is when you hit the save button in word. You dont know all the detail in the background of what is happening to save the file. All you see is the file was saved - you dont want to see the inards of saving. Example - you turn on a sink and water comes out, you dont want to know how the water gets out, just that it works. Simplification.
32
What are the layers of the ring layer protection?
1) Ring 0 = OS Kernel
2) Ring 1 = Operating System components that are not part of the kernel
3) Ring 2 = I/O drivers and utilities
4) Ring 3 = Applications and programs
Note that most systems only use Ring 0 and Ring 3 - if all rings were used, you would have to go to each ring for a system call which would cause latency and slow down the program. Example if when you hit the save button, its easier to go from ring 3 to ring 0 vs. go through every ring to save the file. Grinds away and does every step.
Ring 3 = least secure
Ring 0 = most secure
33
The ____ is a dedicated hardware chip that stores encryption keys.
Pull the disk from the motherboard but without the TPM chip, it wont work, even if you have username and password.
Key use is full disk encryption - if you pull the drive form the laptop and dont have the TPM chip, you cannot decode the data
34
What is virtualization?
Think Cloud...
Virtualization takes an application, desktop, or server and provides virtualized hardware. There is no direct hardware access as all access is via virtualized hardware created by the virtualization software.
the hy[pervisor runs on the host, controlling the virtual machines and their access to the real hardware.The hypervisor is the key to the security. Attacks on virtualization usually target the hypervisor.
Benefits of virtualization - lower hardware costs, cooling and electricity costs, simplified administration (easier patching, backups, etc.), server consolidation, create system snapshots and restore later, clone systems, simpler system testing, simpler BCP
The hardware server is called the host and runs multiple virutalized operating systems (called virtual machine or guests).
VDI - think NYL desktop - Virtual Desktop Infrastructure
VPS - virtual private server (VPS) - virtual machine hosted by a third-party internet hosting company. Offer full VM OS access - you own it. This is similar as putting your own physical server in a co-location, facility, the owner has full control of the server OS.
P2V - physical to virtual - change a physical host to a virtual machine
35
What are the two types of virutalization?
1) Full virtualization - runs unmodified applications or operating systems designed to run directly on computer hardware
2) Para-virtualization - runs specially modified applications or operating systems
36
How do you secure virtualization?
* Still need to patch and harden
* Must properly segment the network
Specific requirements for virtualization:
- protect the hypervisor
- protect the special host
37
What is VM Escape
It is the risk of a successful attach from:
1) virtual machine to host operating system
2) virtual machine to another virtual machine
The attack is against the hypervisor or virtual devices controlled by the hypervisor - all virtual machines and potentially the host itself, are at risk.
This is a risk if you co-mingle VM with different security requirements on the same hypervisor - consider having a different hypervisor for each network.
Basically, the VM gives you access to not just your RAM but other RAM - you can copy on or off to all hypervisor ram, run code on the hypervisor, and therefore, can disrupt other systems and anything on the hypervisor even if you shouldnt have accesss to it. You escape out of your VM to others through the hypervisor and copy data or write code.
You should disable drag, drop, and copy and paste and turn off as many virtual devices as you can.
PATCH your hypervisor routinely!
38
What is a database?
What is a database management system?
1) A collection of related data intended for sharing by multiple users
2) DBMS - stores data and provides operations on the database, such as create, delete, update and search. It also provides security and integrity controls
39
What are two common database language types and functions?
1) Data definition language (DDL) - defines database schema
| 2) Data manipulation language (DML) - examines and manipulates contents of a database
40
Database systems also have serious security issues for CIA. How do you prevent some of those security issues? (mainly integrity)
1) Ensure users do not attempt to access the same data at the same time - control this through use of locks that are imposed on rows or fields in the database. Or use a deadlock. This handles the issue of concurrency (2 people entering into the same cell)
2) Semantic Integrity - wrong data type. ensures that data types, logical values, uniqueness constraints and operations are enforced. Keep track of what type of data is entered and only valid types are accepted. (e.g., if you are recording number of sick days, you cannot have a letter in the field, it should be a number.
3) Entity Integrity - cannot have duplicate keys- ensures each entry has a unique primary key that is not null
4) Referential Integrity - Prevents users from entering inconsistent data - The data must be able to refer back somewhere. All foreign keys must point to an existing primary key or there can be a serious integrity problem.
5) Commit - executed when the changes you make to a record are submitted to the database. As long as the commit is not completed, the information is temporarily stored and not saved
- --- 2-phase commit: vote first before committing (distributed databases). Someone made a change on server a and someone else made a change on server b - server a asks if you are good with this, if server b says no I am not, they roll back to the snapshot
- --- rollback if commit is unsuccessful - when you return to a previous known good state and revert to a specific checkpoint if a problem had arisen
- --- Database returns to its previous state
6) Checkpoint & Database Journal - If a system fails, there is a return to the point before failure. Roll back to the checkpoint and replay the database journal. Checkpoint is not live. So you roll-back to the most recent snapshot, and then you replay the journal which has the log of every change. Restore to a checkpoint and then replay the journal which is every time and therefore you restore integrity
41
What is a data warehouse?
Brings together structured data from disparate data sources. Key goal is to allow for complex queries to be performed in a manager that will not negatively impact an online data store intended for immediate access needs.
42
What is data mining?
Detecting abnormal patterns in large datasets
- --- intrusion detection
- --- fraud detection
- --- auditing the database
think when your bank calls you if you make a purchase out of the country. This is an example of the data mining identifying an abnormal pattern and alerting you
43
What are some security issues with database vulnerabilities and threats?
1) Inference - pentagon pizza story - user deducts information of higher sensitivity from lower sensitivity information.
- --- controls - (1) content dependent access rules (you asked for 5 phone numbers so go away) - (2) Enforced during query processing
2) Aggregation - user has aright to only certain data items in a larger collection of items. The user obtains knowledge that he or she does not have a right to about the larger collection of data.
- --- I will download the whole phone book. You can ask for some peoples extensions, however, if you ask for each extension one by one you can eventually aggregate the whole collection and have the whole collection which you shouldn't have access to.
44
What are the two types of fault tolerance? (redundancy mechanisms)
1) Active-active: All databases are taking transactions simultaneously with synced data. If one computer fails the user does not notice the difference. The failed computer will get fixed while the other computer maintains the availability.
2) Active-passive (shadow) - you have 2 databases with synced data. One takes transactions and one does not. Primary goes down, the secondary stands up
45
What is an applet?
A small Java program downloaded by users who visit web pages. They provide more functionality and a richer experience to users. They are common on dynamic websites or sites that have animated or interactive functions. They are restricted from accessing the local file system or the network. Due to some of the difficulties in delivering applets to a variety of different browsers, a lot of developers have switched to server side Java programs instead. these programs are called ServLets. A remote code also runs on a client which introduces additional risks.
46
What is Java?
Java is a programming language. Is is:
- Object-oriented
- Platform independent - generates bytecode which is interpreted into machine code by Java Virtual Machine (JVM) and can be run cross-platform which is not specific to a processor. You can write one application and run it on Linux, Windows, Mac, etc. Each platform has its own JVM but the JVM runs the same bytecode. You can write one app and be done.
How do you maintain security?
- Sandbox - an application that runs your browser is executed in what is similar to a VM. It does not have the capability to perform functions outside of this box. It protects against malicious applets.
47
What is activeX?
When a user connects to a web page that has an embedded control, the browser's Authenticode technology will verify the signature with the Certificate Authority (CA) that has signed the control to verify it has not been modified. It then downloads the control. Internet Explorer does not allow untrusted or unsigned controls to execute.
Relies on the use of a digital signature that can be disabled by the end-user.
Used a lot to distribute valid patches or updates to users.
It is an object-oriented programming technology and tool.
It can be run anywhere in the ActiveX network, is equivalent to a Java applet and can be created with several languages.
48
OWASP stands for:
Open Web Application Security Project - focused on web application security risks
49
What is clickjacking?
tricks a user into clicking on a malicious link or taking harmful action by putting an innocuous window on top of another one. A window that appears benign is placed over a window that is malicious.
The usr only sees the top window and doesnt realize there is another window below it.
Also called UI redressing.
50
What are cookies?
Cookies are used to store information related to an HTTP session (unique session ID). They can be used to maintain a session state (e.g., active) which identifies a user whilst in the middle of using the applications. A secure session ID should be at least 128 bits in length and random.
The two types of cookies are:
1) Session cookies - in memory and deleted upon browser exit
2) Persistent - saved to disk and may be used long-term.
Cookies can be altered by a user. Secure cookies are transmitted via SSL/TLS only. You can intercept SSL/TLS.
51
What is cross-site scripting? XSS (includes XSRF)
Reflects a scrip via a trusted website that launches an attack on web server clients and commonly uses JavaScript. It is based on a lack of input validation and/or output encoding by websites.
e.g., you can input malicious javascript code into a a blog because there is no input validation into the blog site.
The common goal is to steal cookies (Cross-Site Request Forgery)
Protection - same origin policy - if a site gives me a cookie, only that site can ask for it back.
Protection - input validation:
- --- blacklisting - ban specific characters. Say whats banned and accept the rest
- --- whitelisting - say what you allow and reject the rest (superior to blacklisting)
52
What is a SQL Injection?
Structured Query Language (SQL) is a database language.
Goal of SQL injection is to achieve read/write access to the data tier, via the presentation and logic tier. The attacker sends SQL commands via the web server. This requires poor input validation, allowing characters such as sing quote.
Basically - in an input field, instead of a last name lets say, you enter a SQL code and command the database to spit back information you shouldnt have access to. Can also command the computer to do malicious things like delete the records or manipulate the data.
53
What are thin clients?
Things like citrix - minimizes the complexity on a personal computer, using a universal client such as a browser.
It gets all its apps from the network. Does not download apps directly to the computer itself. Must be connected to the network to get things like web server and mail server and word.
The central server distributes applications and data
They represent a movement back to a centralized model. This removes the need to install specific applications on end systems. The browser is usually already installed.
They lower the TCO of end systems. Applications and data are stored centrally, served out to clients via the browser. Patching and backups are simpler.
However, thin clients are sold by a separate vendor from the OS vendor. The patches are custom from the thin client vendor but come after the OS vendor patch. Original patch from the OS usually cannot be installed on the thin client. There is usually a lag between the thin client vendor and the OS vendor.
54
What are the challenges with mobile device management - configuration management?
There is a need to manage additional devices beyond the typical corporate standard. Management platforms used for laptops/desktops usually will not also support the three most common mobile operating systems (iOS, android, blackberry). Alternate mobile device management suites exist specifically for managing confirmation of smartphones.
Protection:
- encryption
- remote wipe
- backup of data
- unlock code should be required
mobile device management (MDM) systems are better through the use of containers
55
What are some controls you should add for laptop security?
1) full disk encryption
2) patching
3) backups
4) host based security
5) Full tunnel - VPN
56
Internet of Things is:
Internet-connected embedded devices - thermostats, appliances, light bulbs, etc.
Risks
- default credentials are common
- enterprise management tools are lacking
- patching can be difficult
- legacy SCADA protocols are cleartext - no built in security
Hacking into online devices and internet accessible SCADA systems can be searched through SHODAN, a search engine that exposes online devices (e.g., webcams, routers, iphones, etc.)
57
What is a SCADA system
Supervisory Control and Data Acquisition - these are used for industrial applications such as:
- elevators, prison doors, pipelines, heating, electrical grid.
They are pretty insecure because they never used to be connected to the internet. When they were connected, they were not secured as they should be
Key Terms:
- Supervisory system - gathers data and sends commands
- Remote Terminal Unit (RTU) - connects devices to the SCADA network and converts analog data to digital. collects the onsite information and sends it to a central location with the help of the communication element.
- Human Machine Interface (HMI - presents data to the operator. display the information received in an easy to understand graphical way and also archive all the data received.
58
What is centralized vs decentralized vs distributed data?
Centralized - all data is maintained in one place - central data center - all data is in the middle
Decentralized - remote offices maintain/access data locally or centrally - each location has its own local server or the centralized server but can never access another store. servers in each place. no store access another stores servers
Distributed - remote offices maintain / access data locally, other offices or centrally - need to have integrity and the more places you put data the more attack surface there is so make sure to secure that.
- --- Requirements
- portability - ensures that an app easily adapts to different platforms with little effort. Apps that connect to different platforms should connect to these platforms in a unified manner, regardless the type of platform (Linux, unix, etc.). ; interoperability; transparency; extensibility; robustness and security; accommodation of standards; meet users functional requirements
- --- Benefits - mobility; lower cost of infrastructure; system downtime; savings resulting from communication costs; more control over local data
- --- Disadvantages - not always clear how to ensure and maintain all of these entry points at all times; ensure the remote host is not already compromised and cannot be used as a gateway into the corporate infrastructure; larger attache surface
59
The study of secure communications is ____
The study of rendering messages indecipherable except to the intended recipients is ____
The study of code breaking and analysis of cryptographic algorithms and messages is ____
A cryptographic protocol developed from fundamental cryptographic techniques is ____
1) Cryptology - encompasses both cryptography and cryptanalysis and is the generic term for the study of both of them.
2) Cryptography - scientists called cryptographers create the encryption algorithms.
3) Crytpanalysis - those who dedicate their lives to breaking ciphers.
4) Cryptosystem
60
Some key terms for Cryptography are:
1) Plaintext - message in its original form
2) Ciphertext - message in its encrypted form
3) Encryption - creation of ciphertext from plaintext
4) Decryption - transforming ciphertext back into plaintext
5) Ciphers - cryptographic algorithms - the mathematical formula
6) Work factor - effort required to break, rather than decrypt, ciphertext yielding plaintext
61
What is entropy?
It is the amount of disorder (randomness) per bit. A fair coin flip of 50/50 has one bit of entropy.
It is very important for cryptography especially as applied to password and passphrase strength.
The 50/50 element is a 1 or a 0 - so for a 128 bit encryption, there is a 1 or a 0 for 128 bits which makes up the whole key and should be random and different every time.
62
What is Exclusive Or (XOR)?
It is a cipher text which is created by combining a key with plaintext via XOR. The plain text and the key will be compared to determine the ciphertext which are all made up of 1's and 0's. If the plain text and the key (the bits) are the same number (1 or 0) the ciphertext will be 0 (false). If they plain text and key (the bits) are different numbers (1 or 0) the ciphertext will be 1 (true).
If you then apply the key to the ciphertext, it will convert back to the plain text
```
Example:
plaintext = 0110100
key = 1001101
-------------------------------------
ciphertext = 1111001
```
63
What are confusion and diffusion?
Confusion = destroys patterns connecting the key to the ciphertext - substitution provides confusion
Diffusion = destroys patterns connecting the plaintext to the ciphertext - permutation provides diffusion
64
What are rotation substitution ciphers and what are examples?
Rotation substitution ciphers use a one-to-one substitution of characters, so its also easy to break
You rotate the alphabet by x characters
Examples:
1) Caesar Cipher = ROT-3 - rotate the alphabet by 3 characters so A-->D and B --> E, etc.
2) ROT-13 = rotates the alphabet by 13 so A--> N. A second round of ROT-13 brings the alphabet back to its original position.
65
What is arbitrary subsitution?
Swap one letter for another. Replaces one arbitrary letter for another. For example: A-->J , B-->S.
Also known as mono-alphabetic arbitrary substitution
This may be defeated via frequency analysis. There are more common letters in the alphabet so you will see frequency of letters and begin to guess what those letters are
66
What is a polyalphabetic cipher?
user of multiple substitution ciphers. A matrix of 26 alphabets.
Because of the use of multiple alphabets, frequency analysis is countered.
67
What is permutation?
Permutation provides diffusion by diffusing the contents of the plaintext into the ciphertext. It does this by rearranging (permutating) the order
For example - BEAD --> ADEB
Modern day ciphers use both substitution and permutation
68
What is a one-time pad?
A potentially unbreakable cryptosystem. It is unbreakable if:
1) the key is truly random and the randomness is difficult
2) The key is used only once
3) The pads are kept secure
There are two identical pads created where each page contains a matching key. The keys must be random and must be at least as long as the plaintext. A 1,000 byte plaintext requires a 1,000 byte key. Therefore, the ciphertext will also be 1,000 bytes.
69
What are the two general ways to encrypt data?
1) Block cipher = break the data into blocks and encrypt each block
2) Stream cipher = encrypt the entire stream on a bit-by-bit basis
70
What are the goals of cryptography?
1) Confidentiality - by encrypting
2) Data Integrity - data is not altered and if it is we will know. make it possible to prove that the message has not been tampered with and that this message is exactly the same as the one that Alice sent to Bob - use hashing and digital signature
3) Authentication - Prove the identity claim and who the user is. If Alice walks up to Bob and hands him a message, he positively knows that the message is from Alice. Alice might require the cryptosystem to provide an equivalent service for her. Bob must hand deliver messages to her - use asymmetric encryption (public and private key) and a digital signature
4) Non-repudiation - Marriage of data integrity and authentication. You cannot deny you sent something. system should be able to prove that Alice and only Alice sent the message and that it has not been falsified or subsequently altered. In essence, this is a requirement that both authentication and integrity are provable. Both authentication and integrity must be in place to provide non-repudiation. Cannot alter that data or be someone else.
71
What is symmetric key encryption?
Symmetric cryptosystems use a single key for both encryption and decryption. The key must also be a shared secret between sender and receiver.
Faster and stronger than asymmetric but no way to securely share the key
They are:
1) strong and fast
2) not technical
3) requires secure key distribution channel such as pre-shared secret, asymmetric encryption, diffie hellman key exchange
72
What is asymmetric key encryption?
Also known as public-key encryption. Use of two keys - one private and one public. Do not have to pre-share a secret.
slower and weaker compared to symmetric but does not require sharing a key
The primary use of public key cryptography is to provide the exchange or symmetric keys, authentication and non-repudiation
They are:
1) slow
2) trusted channel
3) public keys widely distributed within digital certificates
4) technical non-repudiation via digital signatures
5) private key cannot be derived from public key
6) message encrypted with one key can only be decrypted with the partner key
7) the private key must not be shared
73
What is a hash function (aka message digest)?
One way encryption using an algorithm and no key. This is encryption.
It transforms plaintext into a fixed length string called a hash or message digest.
You cannot run a hash algorithm backwards. There is an extremely low probability that two different plaintext messages will yield the same hash value but they can collide and you must have a good hash that is impossible to brute force.
Primary use is integrity.
74
What are the real world types of encryption methods and hashing methods?
Hashing:
- Hashed Message Authentication Code (HMAC): combines authentication via a shared secret with hashing
- MD5: 128-bit message digest
- SHA 1 (Secure Hash Algorithm): 160-bit hash - proposed by NIST
- SHA 2 = SHA2-56 bit and SHA-512 bit = includes six hash functions.
Symmetric Key Encryption:
- DES (Data Encryption Standard):
- describes the data encyrption algorithm (DEA) - this is the name of the cipher which. The standard is the document that describes DEA. DEA is the algorithm and is a valid answer!
- fast
- symmetric
- Key length = 56 bit
- Block size = 64 bit block cipher
- 1 bit stream cipher
- not secure because of small key size
- Triple DES
- Key Length = 168 bit keyspace (although only 112 after meet-in-the-middle attack
- IDEA (International Data Encryption Algorithm)
- Block cipher intended to be global replacement for DES
- Key length = 128 bit
- Block size = 64-bit
- Challenges = patented algorithm, slower than AES
- international alternative to DES
- licensed - not free - pay to use
- AES = advanced encryption Standard
- Symmetric Block cipher
- Underlying Algorithm = Rijndael (Rhine-doll)
- Block size = 128 bits
- Variable Key Lengths = 128, 192, 256 bits (AES-128, AES-192, AES-256)
- Blowfish
- Symmetric block cipher
- Block size = 64-bit
- Key Length = variable 32-448-bit
- Twofish
- Symmetric block cipher
- Block size = 128 bit
- Key Length = 128, 192, 256
- RC5
- Symmetric block cipher developed by Rivest (RSA)
- Block size = 23, 64 or 128 bit
- Key length = variable 0-2040 bit
- RC6
- AES finalest
- Block size = 128 bit
- Key Length - variable 128, 192, 256 bit
Asymmetric Encryption:
- RSA (prime numbers and factoring (what two numbers multiplied by each other equals this prime number?)
- Discrete logarithm (this to the exponent - what to the what equals this number)
- Eliptical curve encryption - 4 dots on a curve, take away the curve and have the four dots but have to know what the curve looks like
75
What are the five basic modes of DES?
1) Electronic Codebook (ECB)
2) Cipher Block Chaining (CBC)
3) Output Feedback (OFB)
4) Cipher Feedback (CFB)
5) Counter Mode (CTR)
76
What is Electronic Codebook (ECB)?
It is a standard or native mode DES. This is where plaintext message is broken into 64 bit blocks and each block is encrypted with the key. If two blocks of the plaintext are identical, then the corresponding ciphertext is also identical. The othe rmodes of DES are meant to stop this from occurring.
- Weakest operational mode of DES
- Patterns are not destroyed, it is not recommended
Identical plaintext input yields identical ciphertext
- Lack of chaining or feedback allows parallel operations
- Block cipher
- No initialization vector employed
- Errors propagate - no
How do you stop the patterns? They added in chaining (cipher block chaining (CBC).
77
What is Cipher Block Chaining (CBC)?
The system starts off with an Initialization vector. The IV is combined with the key and used to encrypt the first block of text. The encrypted ciphertext of the first block is combined with the key to encrypt the second block of text and the process continues in this fashion. It is used to stop the evidence of patterns (ECB).
kick off with a random block of data, and then XOR the random block with block 0 and then XOR the previous encrypted block to it. Each encrypted block is XOR to the next block
- Requires unpredictable IV for initiating operation
- IV ensures confidentiality given identical or known plaintext
- Operations cannot be carried out in parallel because they are on a chain
- Block cipher
- Initialization vector employed
- Errors propagate - yes (if a bit gets flipped in one block, it will mess up the next block and so on and the data integrity will be lost. the error in the first block will propagate to the subsequent blocks)
78
What is an initialization vector?
A random number meant to seed the encryption.
79
What is Output Feedback (OFB) and Cipher Feedback Mode (CFB)?
Output Feedback:
- Destroy patterns but errors wont propagate
- instead of changing the last block in, it drops bits off the key
- Act as a stream cipher and allows operating on plaintext sizes smaller than typical block (1-bit OFB mode).
- Feedback is stream style equivalent to chaining
- Requires IV
- Errors will not propagate due to how feedback is derived
- Same as CFB but errors will not propagate because of how feedback is derived
Cipher Feedback Mode:
- Similar to CBC but operates like a stream
- Acts as a stream cipher and allows operating on plaintext sizes smaller than a typical block
- Feedback is the stream style equivalent to chaining
- Requires IV
- Errors will propagate
80
What is Counter Mode (CTR)?
- There is a different counter for every block of text (subsequent blocks incremented)
- Used by ATM and IPsec
- 64 bit random number
- Stream cipher
- Counter
- Errors do not propagate
81
Is DES a group? What are examples of groups?
No - DES is not a group because multiple encryptions increase the security. If you encrypt with DES multiple times, it will not be equivalent to encrypting once.
An example of a group is the Caesar Cipher which does not increase security if you encrypt multiple times.
This is how triple DES came to be. However, Double DES is not strong enough and suffers a meet-in-the-middle flaw and is not used.
82
What is Triple DES (3DES, TDES or TDEA)?
Apply three rounds of DES. Increases work factor beyond that required for single DES.
Considered solid but not preferred due to to performance.
Three keys supplied in encrypt, decrypt and encrypt order. Decrypting with a different key further encrypts.
168-bit keyspace bt the key is reduced to 112 bit key due to meet in the middle attack.
83
What is the International Data Encryption Algorithm (IDEA)?
- IDEA (International Data Encryption Algorithm)
- Symmetric block cipher
- Block cipher intended to be global replacement for DES
- Key length = 128 bit
- Block size = 64-bit
- Challenges = patented algorithm, slower than AES
- international alternative to DES
- licensed - not free - pay to use
84
What is Advanced Encryption Standard (AES)?
- Symmetric Block cipher
- Underlying Algorithm = Rijndael (Rhine-doll)
- Block size = 128 bits
- Variable Key Lengths = 128, 192, 256 bits (AES-128, AES-192, AES-256)
This was discovered during a competition. Follow up in the competition was MARS, RC6, Serpent and Twofish
Function names:
- SubBytes - substitutes bytes providing confusion
- ShiftRows - shifts rows providing diffusion
- MixColumns - mixes columns providing diffusion
- AddRoundKey - XORs state with a subkey at end of each round
85
What is Blowfish and Twofish?
- Blowfish
- Symmetric block cipher
- Block size = 64-bit
- Key Length = variable 32-448-bit
- Twofish
- Symmetric block cipher
- Block size = 128 bit
- Key Length = 128, 192, 256
86
What is RC5 and RC6?
- RC5
- Symmetric block cipher developed by Rivest (RSA)
- Block size = 23, 64 or 128 bit
- Key length = variable 0-2040 bit
- RC6
- AES finalest
- Symmetric block cipher
- Block size = 128 bit
- Key Length - variable 128, 192, 256 bit
87
What is tractable vs intractable problems?
Tractable / easy problems:
- symmetric encryption
- can be solved in a polynomial amount of time (quickly).
Intractable / hard problems:
- asymmetric encryption
- think factoring large integers into primes (remember example of integers and prime numbers)
- RSA = factoring larger integers into their two prime factors
- Elliptic curve
- discrete logarithm problem over finite fields
88
What is the Diffie Helman key exchange?
It is a key exchange algorithm. It is not an encryption algorithm but is used to allow for exchanging a symmetric key via a public channel - secure way to exchange keys, normally symmetric keys.
It does NOT provide confidentiality, it only provides a key.
Two parties agree on a symmetric key via a public channel.
I come up with a secret number, you come up with a secret number, I send a third number that is public. Bounce it back and forth and make calculations based on our secret number. You need to have one of the secret numbers.
89
What is RSA?
Asymmetric encryption
Intractable
Factoring numbers into their primes. What times what is this number?
Slower and weaker than DES but is a secure way to exchange keys.
90
What is discrete logarithm?
9^13 = 232424232 and then ask what to the what is that answer
Intractable
91
What is Eliptic curve encryption (ECC)?
Asymmetric encryption
Intractable
If you draw a curve and pick off 4 points on the curve and erase the curve, the curve is the secret and private part. You have the 4 points but not the curve
Offers higher speed, lower power consumption and tighter code. Stronger than RSA and Discrete Logarithm
Low cost, save on CPU, better encryption but with less computational power needed.
Strongest of the asymmetric but not stronger than DES and AES
92
What is code signing?
It is a digital signature for a file / application (code). Vendors much sign their code). This is so you know that the code has not changed
Validates the integrity of the executable and authenticates the executable creator
93
What is Hashed Message Authentication Code (HMAC)
It is like a digital signature that uses a pre-shared key.
This creates integrity. It uses symmetric vs asymmetric encryption.
They are used when the complexity of PKI is not needed or wanted, such as signing zone transfers from a primary DNS server to slaves.
Could also be used for authentication if you know my pre-shared key.
94
What is the best way to use encyrption?
Use both symmetric and asymmetric together!
Modern systems like TLS do this.
Use asymmetric public key to encrypt a key. Only receiver with the private key can open it. Then use the key shared from asymmetric to perform symmetric encryption over the content. Then use hashing to verify the integrity of the session.
95
What is Public Key Infrastructure? (PKI)
PKI provides a technical mechanism for encrypting an organization's data. It is a tool most often used for e-commerce and Business-to business (B2B) and allows users to exchange encrypted information over a public network.
A hierarchy of infrastructure systems is used to create digital certificates
Digital certificates are used to encrypt data.
PKI provides a managed infrastructure for
- creating certificates
- maintaining certs
- revoking certs
RSA is the main algorithm and verisign is a CA
"User A" trusts "PKI Server A" and therefore, "User A" trusts:
- any server signed by "Server A"
- any certificate signed by "Server A"
- any certificate or server trusted by "Server A" or subordinate
Five components of PKI:
- CA - issue and revoke certs
- Organizational registration authorities (ORA) - vouch for the binding between public keys, certificate holder identities, and other
- Certificate holders - issued the cert
- clients who validate the digital signatures and certification paths of a trusted CA
- Repositories that make certs and cert revocation lists available.
Types of trust models for PKI:
- hierarchical
- bridge
- mesh
- hybrid
96
What is a certificate authority?
They are responsible for issuing certificates to individuals (or entities such as web servers) and only CAs are allowed this function within a PKI. When a user or entity wants to join a PKI, they must petition a CA for a certificate. The user presents his credentials, which must be validated. If they pass, the CA creates a certificate based on the user's identity information
A Certificate Practice Standard (CPS) is the document that establishes tightly controlled standard practice for the insurance of certificate. They state:
- how certificates are issued
- how certificates are protected
- how users ensure they continue to be eligible for certificates
Security of the root CA is paramount
- if crhome trusts 400 CAs - one can be the kingmaker of all the certs and if its hacked the underlying certs can be hacked`
97
What is a digital certificate?
it is a credential used to help someone decide whether a key is genuine. It works by binding a public key with identification information such as name and email address. This information is then signed by at least one third party. They bind an individuals identity to a public key.
Current standard for digital certificats is x.509 certificate.
Each cert contains
- x.509 version number
- serial number
- identity info of the certificates owner in the form of a distinguished name (DN)
- owners public key and the algorithm used to generate it
- period that the key is valid
- identity information of the issuing CA
98
What is the online certificate status protocol? (OCSP)
It is designed to overcome the limitations on CRL.
It offers real-time notification of revoked certifications.
99
What is escrowed encryption?
Have a central authority which contains a copy of everyones key so the CA can decrypt any message they want. It is a third party that is trusted and maintains a copy of your key in case need to decrypt something.
Governments, lawmakers use this so multiple people can get access to the key.
Divide the key in half - give half to one organization and half to another so that when they come together you have the full key. This is how you can get the key that is stored in a third party. this helps with separation of duty. you can divide it as much as you want.
100
What is pretty good privacy?
First free and easy to use encryption that combined:
- symmetric, asymmetric and hash ciphers
- digital signatures
- secure communication without pre-sharing a key
PGP is decentralized unlike PKI. There is no CA at the top. you dont pay money for certs. It uses a decentralized Web of Trust Model
- web of trust model is that I generate my own digital certificate, if I trust you, I trust your certificate, It may also work in reverse - you trust me and my certificate. Then it expands if you trust me, then your friend may trust me. If I trust you, I could decide to trust everyone you trust.
There were no free implementations of asymmetric encryption before but PGP used RSA
101
What is transport encryption?
Transport encryption protects data in motion as it moves across a network. It provides end-to-end encryption
Example is VPN
- IPsec
- SSL/TLS (CA)
- SSH (no CA)
102
What is SSL and TLS?
Secure Sockets Layer (SSL) and Transport Layer Security (TLS) protect packet data above the transport layer
TLS 1.0 = SSL version 3.1
- TLS is an upgrade to SSL3.0
- Retains backward compatibility with SSL
- Current TLS version is 1.2
SSL for web traffic but TLS has evolved to cover smail and chat, etc. It can be used as a tunneling protocol
103
What is IPsec?
IPsec is a type of transport security to encrypt information. It is a protocol with two primary encryption algorithms:
- AH: Authentication Header - protects the entire packet including headers. It provides authentication and integrity but no confidentiality. It acts as the digital signature for the packet
- ESP: Encapsulating Security Payload - provides confidentiality, integrity and authentication - protects the payload
****Remember - AH provides NO confidentiality
You can use AH, ESP or both. You can use only AH if you want. You certainly want ESP but mostly you want both.
104
What is an IPsec Security Association (SA)?
On-way connection that allows endpoints to negotiate details for AH or ESP communication.
Bi-directional communication would require two SAs.
Each SA can only accommodate either AH or ESP but not both
Each SA can only accommodate either AH or ESP, but not both
105
What is perfect forward secrecy (PFS)
If key 1 is used to generate key 2 session and key 1 is compromised or know, key 2 session is still safe.
This is used to protect session keys. This is used commonly in IPsec
Previous symmetric session keys remain secure, even if the private key or other session keys are compromised.
106
What is Secure Shell (SSH)?
A Replacement for insecure protocols such as:
- telnet - plain text - protected by SSH
- FTP
- rlogin
- rshell
provies secure network terminal access and file transfer. It can also be used as a VPN tunnel to other protocols like http.
It operates on TCP port 22
v2 is preferred over v1
107
What are the types of crypto attacks?
1) Brute force - try all combinations of keys and passwords
2) Man-in the middle - attacker intercepts messages between two parties
3) ciphertext only - portion of ciphertext is known
4) Known plaintext - portions of plaintext and corresponding ciphertext are known - have known matching plain and cipher text
5) chosen plaintext - you choose the plaintext you want encryptied and then can see the resulting ciphertext which may give clues about the key
6) adaptive chosen plaintext - chosen plaintext attack with iterations of input is based on knowledge of output - after choosing plaintext, you can also choose other blocks to be encrypted. This allows even more analysis based on the results of each encryption step.
7) Chosen ciphertext only - encrypted messages; no plaintext is available. Recover one or more plaintext messages or the key used to encrypt the messages
8) chosen ciphertext - choose the ciphertext to be decrypted. with a portion of the ciphertext, you attempt to obtain the corresponding plaintext. Primarily used against public-key ciphers
9) Chosen key attack - knows something about a specific relationship between the keys. do not choose the key but can help crack the key.
10) Analytic - use algorithms and mathematics to deduce key or reduce key space to be searched
11) statistical - using statistical characters of language or weaknesses in keys
12) differential - analyze resultant differences as related plaintexts are encrypted using a cryptographic key - if you change the plaintext in a specific way, will the key change the same and show relationships between ciphertext. If you make this change in plaintext do you see the same type of change in ciphertext?find non-randomness if possible
13) linear - linear analysis of pairs of plaintext and ciphertext - line them up and do a whole bunch and find a non-random key - for plaintext
14) Differential Linear - applying differential analysis with linear analysis
15) side-channel attack - using physical data to break a cryptosystem - example, monitor CPU utilization to see how hard it is working as it encrypts and decrypts. data
108
What is a birthday attack?
When 23 people are put tother, the odds are greater than 50% that two people share a birthday. This relates to the probability to the likelihood of hash signatures collisions existing.
Output of a hash is not always unique - there can be a collision - every md5 hash is 128 bits - if you hash 10k files - 1,000 bytes and creates 128 bit output. Theres more bytes of output then the hash bits so there will be a collision
109
What is steganography?
Concealing the fact you are sending sensitive information by hiding data within a file such as an image or sound file. So that the meaning of the message and the fact that a message is being sent is concealed.
This provides secrecy - cryptography provides confidentiality but not secrecy.
With stego - you may not even know that someone is sending a message as you are hiding the true intent
110
What are examples of contraband checks?
They are detective measures such as x-ray machines, metal detectors and bag inspections. The are primarily detective but can also deter someone from doing something if they think they will be caught.
If you have files or a USB in your bag that you are trying to sneak out with data it will be check
111
Closed Circuit Television (CCTV)
Cameras are detective controls. It may also deter someone if they see the camera.
Depth of field - Bright light gives you a much wider view and what is in focus. you must have enough light in the parking lot to make sure things are in focus. Do you have enough light to have a proper depth of field (light needs to be 2 candle power)
Field of view - what is in the frame
CCD is modern
112
What are the heights of fences?
Varying heights provide varying levels of protection.
Need to know the heights in ft and meters:
1) 3-4ft / 1 meter = deterrent
2) 6-7 / 2 meters = to high to easily climn
3) 8 ft / 2.4 me + 3 strands of barbed wire = preventative
113
Types of gates
Class I = residential gate
Class II = commercial gate (garage)
Class III = industrial gate (loading dock, factory)
ClassIV = restricted access (prison, airport)
114
What is a mantrap?
Secure portal that require the individual to provide sufficient identification for the gateway to open toward the restricted area.
There are two doors. it prevents piggy backing.
Physical preventative control
intruder confined between 2 doors
need an emergency button to enable exit without identifying.
115
Restricted Area definition:
```
Guard = armed guard on the exam
Pseudo guard = unarmed guard
- check entrance credentials
- issue and recover visitor badges
- monitor cctv
```
Use the following for restricted areas:
- motion detector
- escort from restricted area (employee or guard)
- perimeter
- show restricted vs non restricted access for a visitor. and separate the areas
- educate "employees only" sign
- discourage - uniformed pseudo guards (unarmed)
116
Good to use a dog or not for physical security?
used mainly for perimeter security in controlled and enclosed areas
- might use for contraband recovery
have good hearing and night vision - good for low-light and lightly trafficked areas
They cannot check badges or make decisions.
dog is usually binary - they are either biting you or not biting you. They know to attack or not attack
A question on a dog is that they are a liability on the exam - they are a liability. insurance costs could increase.
***Answer is liability!!
117
What are types of badges?
1) photo - dumb card - needs a person to verify access which is a down fall
2) digitally encoded - smart card and memory card
118
What are the requirements for lights?
Need 2 candle power of light for adequate depth of field.
- two candle power is if you had white paper and two candles and one foot away from the paper the paper is not lit to 2 candle power.
Light is also 8 ft tall
If you have a parking lot illuminated, the whole parking lot must be lit to 2 candle power to whatever is watching it.
Light is the same height as the preventive fence
119
If you are asked to build a datacenter on a greenfield. what is the BEST location for a datacenter?
1) higher ground to avoid floods
2) reliable utilities (electric)
3) safe neighborhood
4) earthquake faults
5) do not label a data center in any special way
6) do not put in the basement
7) do not have shared walls with your neighbors
8) do not have shared demarc - telecom - circuts enter the building here. where the ISP responsibility stops and yours starts - people can get into this
9) near transportation for ease of access
10) not near high traffic area
11) do not want shared tenancy
12) close proximity to fire, police and hospital
120
How do you want your facility to be designed (physical security)
Slab to slab
Walls, ceilings, floors - 1 hour fire rated - resistant to fire, takes 1 hour for the wall to fail
Wall Fire rating - how long it will resist against fire
Doors - is it solid core, hollow core is weak. Need solid all the way through.
Are there raised floors? - can you scoot under it?
Have slab to slab construction - does the wall go all the way to the top and all the way to the bottom
dont want static buildup - can cause a fire
mail slots are bad - they can be used to gain access or information.
121
Doors (physical security)
Panic button to allow people to get out
doors open out not in
how the door is installed is critical, if the higns are on the outside facing a non-secure area, someone can pop them and remove the door.
Door opening should not block a critical point for safety and should always swing out not in
All exits must be clearly marked and never blocked
122
Locks (physical security)
Lock-bumping - make the pins inside jump and flip open the lock - can do it very fast and makes it look like you unlocked it with the key
locks only buy you time, they all can be picked or bumped
combination locks - offer little as well
123
What are the requirements for wiring closet security?
- Always securely locked
- Secure the demarcation - demarc is the point where voice and circuits enter a building. It is the point where the client's responsibility for voice and data network equipment begins and the ISP's responsibility ends. Access to the demarc puts the CIA of all data flowing through it at risk.
- Wires should never be intermingled. do not intermingle power and network cables.
- This can lead to increases in total cost of ownership of future management and increase the likelihood for future mistakes (e.g., unplugging the wrong cable). Can also lead to crosstalk: an electric signal bleeding from on cable to another and violate integrity.
124
What are the security requirements for a server room?
- All dimensions should be equally secure - walls, doors, windows, floors, ceilings.
- All walls, doors, windows, floors and ceilings should have a on-hour fire rating****
Walls should go to the true floor and the true ceiling - slab to slab
125
What are the security requirements for media storage facilities?
- All sensitive backup data should be stored off-site and encrypted
- Sites using backup media should follow strict procedures for rotating media off-site
- Always use a bonded and insured company for off-site media storage
- Be sure that the storage site is unlikely to be impacted by the same disaster that may strike to primary site
- Never use informal practices, such a storing backup media at an employees house
126
What are the security requirements to lock down
- Servers
- Workstations
- Laptops
Servers-
Should be placed in a physical location that is protected such as a server room or locking cabinet. Each server should have some or all of the following: Tamper-proof seals, disabled removable media, disabled external ports and faceplate locks
Workstations-
We must trust that physical access to workstations will be protected by the building security. Other prevention measures include floppy locks, disabled removable media, BIOS passwords, tamper-proof seals, visual perspective limiters (screen filerts), idkle use screensavers, password locked screen savers.
Laptops-
Laptops have all the same issues as workstations without the protection of the location's physical security. PC and biometrics, leash locks, lockable luggage. BIOS passwords, multi-factor authentication, file encryption, disk encryption
Additional controls include
- port controls
- pc locking devices
- switch controls
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HVAC considerations
everything goes out - untreated air and water go out. nothing comes in.
Should not have people working in the data center. You can have personnel going in and out but they should not be sitting there all day long. the humidity and temperature is designed for the machines not humans.
*humidity should be 50% + or - 10 (between 40-60%) - low humidity can cause static (fry equipment) and high humidity can cause moisture/ corrosion
**temperature should range 70-75 F and 21-23 C
Green data centers - run at 80 F - with proper cooling its ok. Means you have the right cooling and equipment
How to help against humidity -
- propoer humidity level
- antistatic flooring and sprays
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What are air quality considerations
Aiborne particulate levels should be maintained at appropriate levels. Dust and other contaminants can impact sustained operations of computer hardware
Excess concentration of certain gases can accelerate corrosion and cause failure in electronic components.
Air flowing in and out of the room is carfully controlled and filtered.
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Electrical power considerations:
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Noise - unwanted electrical signals
Electromagnetic interference (EMI) and Radio Frequency interference (RFI) - unwanted signals generated by electric motors, fluorescent lighting, computer systems and so on
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Protection methods:
- shielding
- proper grounding
- conditioning of power lines
- care in routing of cables
Definition:
- Fault - momentary power loss
- Sag - Momentary low voltage
- Brownout - prolonged low voltage
- Blackout - loss of all power
- Spike - Momentary high voltage
- Surge - Prolonged high voltage
- Transient - Short duration noise interference
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Smoke and fire considerationg:
Detective
- smoke detectors (by smoke interfering iwth alight beam OR as a result of change in the ionization current generated by a minute radioactive source
- heat sensors (detect the temperature in the room or detect the rate of change of temp in the room
- flame detectors (sense the pulsation of the flame or sense the IR energy produced by the flame)
You always want smoke detectors - the flame detectors need line of site and see the fire. smoke detectors and then aim a fire detector that might catch on fire.
Suppressive
- Sprinklers (chemical, H2O)
- Fire extinguishers (ABC, Halon)
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What are the fire classes?
A - think Ash- Common Combustibles - woode products, laminates - supress with water or soda acid)
B - think banana suit - liquid - petroleum products, coolants, etc. (supress with gas (halon, CO2, and soda acid)
C - think conductive - electrical - electronic equiment, wires - suppress with gas, CO2
D - combustible metals (suppress with dry powder)
Co2 and soda acid remove fuel and oxyen
Water removes temperature
Gas interferes with chemical reactions between elements - halon you fill the room bottom to top
WATER is the safest for humans in the absence of electicity
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Types of fire suppression systems:
1) wet pipe - always filled with water up to the sprinkler head. When the temp exceeds 165 F the material holding back the water melts and releases the water
2) Dry pipe - water is not filled up to the sprinkler head. It is held back at a distance from the sprinkler by a valve. When the temp in the room reaches or exceeds 164 F the valve opens. Air that is in the pipe is expelled and the water begins to flow. In this approach the delay allows computer systems to power down to avoid water damage
3) pre-action - hybrid of wet and dry pipe - when temp is reached, the valve opens and releases water to the nozzle head. Then, the link in the nozzle head melts and releases water. Head senses 165 and temp senses 165. - there are two sensors here and use this in more instances you want to be absolutely certain
4) deluge - similar to dry pipe, sprinkler releases a large amount of water when discharging.
5) gas discharge - discharges an inert gas such as CO2 or Halon, usually installed under the floor of the computer area
6) portable extinguishes to minimize fire damage - filled with an approved/applicable suppression agent and located within 50 ft of any electrical equipment
7) Water - preferred method by insurance companies and safest for humans
8) CO2 - removes oxygen and is partially lethal - gas masks give no protection but its best for unattended facilities - use a built in delay in manned areas
