Repeaters (Layer 1) – amplify signal, no added intelligence, no filtering

Hubs (Layer 1) – used to connect multiple LAN devices, no added intelligence

Bridges (Layer 2)

• Amplifies signal and adds some intelligence
• Forwards the data to all network segments if the Media Access Control (MAC) or hardware address of the destination computer is not on the local network segment
• Automatically forwards all broadcast traffic

Planning to take the CISSP Exam? Get a copy of my personal notes (300plus pages worth) that I used to pass the exam for only $25.00. Click the Add To Cart Button to Purchase Plus you will also get copies of notes from other CISSPs. Learn more about this package by visiting this blog entry: CISSP REVIEW NOTES I USED TO PASS THE EXAM. CLICK BELOW TO MAKE YOUR PURCHASE NOW. All Purchases are securely processed through Paypal. Once you click the button please check your shopping cart at the upper right hand side of the page to complete your order. IMPORTANT NOTICE: I MANUALLY REVIEW ALL ORDERS. SO ONCE YOU PURCHASE THE PRODUCT, THERE WILL BE SOME DELAY ON YOU RECEIVING AN E-MAIL FROM ME WITH THE LINK TO THE DOWNLOAD AREA OF THE PRODUCT. YOU WILL GET A RESPONSE FROM ME WITHIN 24-48 HOURS. You may also want to consider these CISSP resources from Amazon.com

Switches (Layer 2) – Will only send data to the port where the destination MAC address is, not to all ports

Routers (Layer 3) – opens packet and looks at either MAC or IP address and forwards the packet to the destination network

Gateways – primarily software, can be multi-protocol and can examine the entire packet

Asynchronous Transfer Mode (ATM) Switches – use relay technology and typically used in WANs and CANs.

LAN Extenders

• Remote access multi-layer switch connected to a host router
• Filters based on MAC address, but not capable of firewalling

WAN Technologies

• Rules for communicating between computers on a WAN
• Communications between large disparate networks

Private Circuit Technologies

• Evolved before packet switching networks
• Dedicated analog or digital point-to-point connection
• Serial Line Internet Protocol (SLIP), Point-to-Pont Protocol (PPP), ISDN and xDSL
• Dedicated Line – indefinitely and continuously reserved for transmissions
• Leased Line – type of dedicated line leased from a carrier

Types and Speeds of Leased Lines

Digital Signal Level 0 (DS0) – single channel at 64KBps on a T1

Digital Signal Level 1 (DS1) – 1.544 MBps in US on a T1 and 2.108 MBps in Europe on an E1

Digital Signal Level 3 (DS3) – 44.736 MBps on a T3

T1 – transmits DS-1 data at 1.544 MBps on telephone switching network

T3 – transmits DS-3 data at 44.736 MBps on telephone switching network

E1 – predominantly used in Europe and carries data at 2.108 MBps

E3 – predominantly used in Europe and carries data at 34.368 MBps

SLIP (Serial Line Internet Protocol)

• Developed in 1984 to support TCP/IP over low speed serial interfaces
• Using Windows NT RAS, NT computers can use TCP/IP and SLIP to communicate to remote hosts

PPP (Point to Point Protocol)

• Used over dial-up and dedicated links
• Includes login, password and error correction
• Operates at Layer 2 and uses CHAP and PAP

ISDN (Integrated Services Digital Network)

• Integration of digital telephony and data transport
• Digitization of the telephone network, allowing voice, data, etc.
• Overtaken by DSL

xDSL (Digital Subscriber Line)

• Uses existing twisted pair telephone lines
• ADSL (Asymmetric DSL)
  • More bandwidth downstream (1.5 to 9 MBps) than upstream (16 to 640 KBps)
  • Works at 18000 ft theoretical lengths and 14400 ft practical lengths over copper twisted pair
• SDSL (Single-line DSL)
  • Provides from 144 KBps up to 1.544 MBps in both downstream and upstream traffic, depending on the distance from the carriers point of presence (POP) over copper twisted pair
  • Works at 10000 ft lengths
• HDSL (High-rate DSL)
  • 1.544 MBps both up and down over two copper twisted pair (T1 speed)
  • Can do 2.048 MBps on three copper twisted pair
• VDSL – (Very High-rate DSL)
  • 13-52 MBps down and 1.5 MB to 2.3 MBps upstream over single copper twisted pair operating range 1,000 – 4,500 feet

You may also want to consider these CISSP resources from Amazon.com

One thing that I’d like to point out though, it does not take a genius to create a strong password, which for all accounts and purposes there is no such thing. It gives as much protection as a locked door knob to your house. It gives you a layer of protection, but not the protection. Just like a door knob, it can help prevent casual intruders, but not those who are really intent in breaking in. But, I digress.

In any case, I figured I give a quick comment on this matter since this somehow ties in to what I do for a living and what I preach to users practically on a daily basis.

First point of fact: It does not take a genius, knowledge of nuclear science or for that matter hours of deliberation to create a strong password. Typically a password with 8 characters utilizing 3 of the 4 types of characters in your keyboard is often sufficient.

Password1 is a strong password. Although I would not recommend using this password exactly, it meets the requirements I stated above. It has more than 8 characters, uses the upper case letter, lower case letter and a number, 3 of the 4 types of characters required. To make this password even technically stronger, add a special character, i.e. !Password1.

Now was that hard?

Second point of fact: even if your company requires you to change your password regularly, you don’t need to build a special database to maintain all these passwords. Going back to our Password1 example, if you need to change it, develop a simple system that will be easy to remember and follow. In this case a simple change, such as Password2, will often be sufficient. So all you have to remember is that you changed your password to the next number up. Many companies only prevent users from re-using passwords within the first three changes, so if your company requires a password change once very quarter, you can rotate from Password1 to Password4 every year: Password1 for the first quarter, Password2 for the second quarter and so on.

Now was that too time consuming?

Third and final point of fact: Companies and organizations who require password set-ups far and above what I mentioned above, i.e. requiring passwords 14 characters long, requiring all 4 character types used and not allowing reuse of passwords even after 4 or more changes (yes I’ve run into policies like these) are who this article should be referring to. In my personal and professional opinion, these policies, for a lack of a better word, are moronic policies and do not provide the organization with better benefits or security. They often tend make the organization more insecure as users will find ways to circumvent these rules like writing it on a post-it note and pasting it on the monitor. How many of you have passwords written behind your keyboard?

So what do I do personally?

Personally, I maintain only three password combinations and don’t change them unless I really have to. If I have to, I typically just do the slight variations that I mentioned above and no, Password1 is not one of them.

To read about the research by Cormac Herley mentioned in the article: The Rational Rejection of Security Advice by Users.

On a side note, I just found it peculiar that the research was sanctioned by Microsoft, a company well-recognized for their vigilance in maintaining the security of their products.

• Physical & Data Link Layers
• Controls the use of a network

Ethernet 802.3

• Uses CSMA/CD
• Designed for sporadic traffic
• Defines a bus topology with 3 different cabling standards:
  • Thinnet (10Base2) – coax with segments up to 185 meters
  • Thicknet (10Base5) – coax with segments up to 500 meters
  • Unshielded Twisted Pair (UTP) – all devices connected to a hub or a switch

Planning to take the CISSP Exam? Get a copy of my personal notes (300plus pages worth) that I used to pass the exam for only $25.00. Click the Add To Cart Button to Purchase Plus you will also get copies of notes from other CISSPs. Learn more about this package by visiting this blog entry: CISSP REVIEW NOTES I USED TO PASS THE EXAM. CLICK BELOW TO MAKE YOUR PURCHASE NOW. All Purchases are securely processed through Paypal. Once you click the button please check your shopping cart at the upper right hand side of the page to complete your order. IMPORTANT NOTICE: I MANUALLY REVIEW ALL ORDERS. SO ONCE YOU PURCHASE THE PRODUCT, THERE WILL BE SOME DELAY ON YOU RECEIVING AN E-MAIL FROM ME WITH THE LINK TO THE DOWNLOAD AREA OF THE PRODUCT. YOU WILL GET A RESPONSE FROM ME WITHIN 24-48 HOURS. You may also want to consider these CISSP resources from Amazon.com

ARCNet (802.5)

• Early LAN technologies
• Uses token passing in a Star topology on coax cable

Token Ring

• Second to Ethernet
• All end stations connected to a Multistation Access Unit (MSAU)
• One station is designated as the Active Monitor
• IF a transmitting station fails, the Active monitor will remove the token and generate a new one

Fiber Distributed Data Interface (FDDI)

• Dual token ring LAN at 100 MBps on Fiber
• Dual counter rotating rings only one active at a time
• Operates over long distances with minimal interference
• Predictable delays, deterministic
• Permits several tokens to be present at a time
• Expensive and requires special expertise
• Copper Distributed Data Interface – can be used with UTP cable, but subject to interference and length issues associated with copper

You may also want to consider these CISSP resources from Amazon.com

The first in a series of video’s looking at common Internet threats. This one looks at Phishing and how to prevent it.

Bus

• All transmissions travel full length of the cable and receive by all other stations
• Single point of failure n the cable
• If one of the links between any of the computers is broken, the network is down
• Primarily Ethernet
• These networks were originally designed to work with more sporadic traffic

Planning to take the CISSP Exam? Get a copy of my personal notes (300plus pages worth) that I used to pass the exam for only $25.00. Click the Add To Cart Button to Purchase Plus you will also get copies of notes from other CISSPs. Learn more about this package by visiting this blog entry: CISSP REVIEW NOTES I USED TO PASS THE EXAM. CLICK BELOW TO MAKE YOUR PURCHASE NOW. All Purchases are securely processed through Paypal. Once you click the button please check your shopping cart at the upper right hand side of the page to complete your order. IMPORTANT NOTICE: I MANUALLY REVIEW ALL ORDERS. SO ONCE YOU PURCHASE THE PRODUCT, THERE WILL BE SOME DELAY ON YOU RECEIVING AN E-MAIL FROM ME WITH THE LINK TO THE DOWNLOAD AREA OF THE PRODUCT. YOU WILL GET A RESPONSE FROM ME WITHIN 24-48 HOURS. You may also want to consider these CISSP resources from Amazon.com

Ring

• Unidirectional transmission links form closed loop
• Token Ring and FDDI
• Similar to the Star topology, however there’s a device called a Multistation Access Unit (MAU)
• MAU works the same as a hub, but with Token Ring networks instead of Ethernet networks
• These networks were originally designed to serve large, bandwidth-intensive applications

Star

• Nodes connected to a central LAN or a junction box called a hub or a concentrator at the center of the network
• Provides reliability and often used by Bus and ring topology as the physical connection

Tree – branches can have multiple nodes

Mesh – all nodes are connected to every other node

You may also want to consider these CISSP resources from Amazon.com

Twisted Pair Cable

• Relatively slow speed
• Two insulated wires can be shielded (STP0 or unshielded (UTP)
• UTP is four-pair medium and comes in several categories
• UTP can be easily tapped by eavesdroppers than the other cable types
• Category based on how tightly wound the wires are, the tighter the wind the higher the rating and the higher the resistance to interference
• Cat 1 UTP – was used for telephone lines, not good for data
• Cat 2 UTP – up to 4 MBps
• Cat 3 UTP – Used for 10BaseT networks up to 10 MBps
• Cat 4 UTP – Used in Token Ring Networks up to 16 MBps
• Cat 5 – Current UTP standard for new installations up to 100MBps
• Cat 6 UTP – up to 155MBps
• Cat 7 UTP – up to 1 GBps

You may also want to consider these CISSP resources from Amazon.com

Planning to take the CISSP Exam? Get a copy of my personal notes (300plus pages worth) that I used to pass the exam for only $25.00. Click the Add To Cart Button to Purchase Plus you will also get copies of notes from other CISSPs. Learn more about this package by visiting this blog entry: CISSP REVIEW NOTES I USED TO PASS THE EXAM. CLICK BELOW TO MAKE YOUR PURCHASE NOW. All Purchases are securely processed through Paypal. Once you click the button please check your shopping cart at the upper right hand side of the page to complete your order. IMPORTANT NOTICE: I MANUALLY REVIEW ALL ORDERS. SO ONCE YOU PURCHASE THE PRODUCT, THERE WILL BE SOME DELAY ON YOU RECEIVING AN E-MAIL FROM ME WITH THE LINK TO THE DOWNLOAD AREA OF THE PRODUCT. YOU WILL GET A RESPONSE FROM ME WITHIN 24-48 HOURS. You may also want to consider these CISSP resources from Amazon.com

Coaxial Cable

• Hollow outer conductor surrounds inner wire conductor
• Currently two types of LAN
  • 50-ohm Cable for digital signaling
  • 75-ohm Cable for analog signaling and high-speed digital signaling
• More expensive, but is more resistant to Electromagnetic Interference (EMI)
• Used rarely except in Broadband communications
• Comes in two types:
  • Thinnet – RG58
  • Thicknet RG8 and RG11
• Two common types of coaxial transmission methods:
  • Baseband – The cable carries a single channel
  • Broadband – Cable carries several channels

Fiber Optic Cable

• Conducts modulated light transmission
• Light waves are faster and travel greater distances
• Difficult to tap
• Resistant to EMI
• Usually connects backbones in larger networks
• Can be used to connect workstations to the network
• Expensive to install and to terminate

LAN Transmission Protocols

• Rules for communication between computers on a LAN
• Formatting of the data frame, the timing and sequencing of packet delivery, and resolution of error states

Carrier Sense Multiple Access (CSMA)

• Foundation of the Ethernet protocol
• Workstation continuously monitors the line waiting until it thinks it is free
• If the workstation doesn’t receive an acknowledgement from the destination to which it sent the packet, it assumes a collision has occurred and it resends the packet
  • Persistent Carrier Sense – Unless it receives an acknowledgement it will resend
  • Non-persistent Carrier Sense – Waits a random amount of time before it resends

CSMA/CA

• Carrier Sense Multiple Access / Collision Avoidance
• Workstations connected to two coax cables, one to send and one to receive data

CSMA/CD

• Carrier Sense Multiple Access / Collision Detection
• If the host detects another signal while transmitting it will send a jam signal causing all nodes to stop sending data
• Nodes will wait to resend
• Designed to avoid collisions

Polling

• A primary workstation polls another at a predetermined time to determine if it has data to transmit
• Primary must give permission to others to transmit

Token Passing

• Token Ring, FDDI and ARCnet
• Cannot transmit without the token
• Each station can hold token for maximum predetermined amount of time

LAN Transmission Methods

• Refer to the way packets are sent on the network
• Unicast – from single source to single destination
• Multicast – source copied and sent to multiple destinations
• Broadcast – source copied and sent to all nodes on the network

You may also want to consider these CISSP resources from Amazon.com

Mail Services – Send and receive e-mail internally and externally

Print Services – Print documents to shared printers

Client/Server Services – Allocate computing resources among workstations

Planning to take the CISSP Exam? Get a copy of my personal notes (300plus pages worth) that I used to pass the exam for only $25.00. Click the Add To Cart Button to Purchase Plus you will also get copies of notes from other CISSPs. Learn more about this package by visiting this blog entry: CISSP REVIEW NOTES I USED TO PASS THE EXAM. CLICK BELOW TO MAKE YOUR PURCHASE NOW. All Purchases are securely processed through Paypal. Once you click the button please check your shopping cart at the upper right hand side of the page to complete your order. IMPORTANT NOTICE: I MANUALLY REVIEW ALL ORDERS. SO ONCE YOU PURCHASE THE PRODUCT, THERE WILL BE SOME DELAY ON YOU RECEIVING AN E-MAIL FROM ME WITH THE LINK TO THE DOWNLOAD AREA OF THE PRODUCT. YOU WILL GET A RESPONSE FROM ME WITHIN 24-48 HOURS. You may also want to consider these CISSP resources from Amazon.com

Domain Name Service

• Matches Internet Uniform Resource Locator (URL) with the actual IP address of the server providing the URL
• Maps host names to IP addresses
• Domain Name System (DNS) – global network of servers that provide this service

• Local Area Network (LAN)
• Wide Area Network (WAN)
• Internet, Intranet and Extranet

You may also want to consider these CISSP resources from Amazon.com

Local Area Networks (LAN)

• Discrete network for limited geographical area like a building or a single floor
• Two LAN Variations
  • CAN (Campus Area Network) – connects multiple buildings with each other over a switched backbone
  • MAN (Metropolitan Area Network) – LAN over a city wide metropolitan area
• Both CAN and MAN can have a connection fot WAN

Wide Area Networks (WAN)

• Network of sub-networks that interconnect LANs over large geographic areas
• Everything outside of the LAN (router is involved)

Planning to take the CISSP Exam? Get a copy of my personal notes (300plus pages worth) that I used to pass the exam for only $25.00. Click the Add To Cart Button to Purchase Plus you will also get copies of notes from other CISSPs. Learn more about this package by visiting this blog entry: CISSP REVIEW NOTES I USED TO PASS THE EXAM. CLICK BELOW TO MAKE YOUR PURCHASE NOW. All Purchases are securely processed through Paypal. Once you click the button please check your shopping cart at the upper right hand side of the page to complete your order. IMPORTANT NOTICE: I MANUALLY REVIEW ALL ORDERS. SO ONCE YOU PURCHASE THE PRODUCT, THERE WILL BE SOME DELAY ON YOU RECEIVING AN E-MAIL FROM ME WITH THE LINK TO THE DOWNLOAD AREA OF THE PRODUCT. YOU WILL GET A RESPONSE FROM ME WITHIN 24-48 HOURS. You may also want to consider these CISSP resources from Amazon.com

Internet – WAN originally funded by the DoD and uses TCP/IP

Intranet

• Internet-like logical network that uses a companies internal physical network structure
• More security and control than Internet
• Uses Internet tools like browsers

Extranet

• Extranet can be accessed by users outside of the company, (i.e. vendors and partners), but not the general public
• Includes come type of authentication or encryption

Asynchronous vs. Synchronous Communications

• Asynchronous
  • Basis of modem and dial-up remote access
  • Must operate at same speed
  • Start and stop bits mark the beginning and the end of each transfer
• Synchronous – very high speed and governed by clock timing signals

You may also want to consider these CISSP resources from Amazon.com

So I Googled, “CISSP Domain 2”.  The result was TechTarget’s SearchSecurity.com listed at number 1. And it says “CISSP Domain 2 quiz: Access Control.” Access Control? What do you mean Access Control? I thought “Telecommunications and Network Security” is the CBK”s Domain 2?

At first I thought it was a mistake by TechTarget, but as I go down the Google search result they all say Access Control. Was I smoking something when I was typing my notes 4 years ago? You are probably saying, “well Don, what is the big deal?” It sort of kinda a big deal, since if you have been following my entries in this blog, I have Access Control listed as Domain 1 and Telecommunications and Network Security is Domain 2. Don’t want to end up losing street cred here . Plus really it bugs me not being able to figure out how I could have done such a mistake.

So I visited the original source, I went to ISC2.org and looked up how they listed the domains. And this is what I found:

• Access Control
• Application Development Security
• Business Continuity and Disaster Recovery Planning
• Cryptography
• Information Security Governance and Risk Management
• Legal, Regulations, Investigations and Compliance
• Operations Security
• Physical (Environmental) Security
• Security Architecture and Design
• Telecommunications and Network Security

Planning to take the CISSP Exam? Get a copy of my personal notes (300plus pages worth) that I used to pass the exam for only $25.00. Click the Add To Cart Button to Purchase Plus you will also get copies of notes from other CISSPs. Learn more about this package by visiting this blog entry: CISSP REVIEW NOTES I USED TO PASS THE EXAM. CLICK BELOW TO MAKE YOUR PURCHASE NOW. All Purchases are securely processed through Paypal. Once you click the button please check your shopping cart at the upper right hand side of the page to complete your order. IMPORTANT NOTICE: I MANUALLY REVIEW ALL ORDERS. SO ONCE YOU PURCHASE THE PRODUCT, THERE WILL BE SOME DELAY ON YOU RECEIVING AN E-MAIL FROM ME WITH THE LINK TO THE DOWNLOAD AREA OF THE PRODUCT. YOU WILL GET A RESPONSE FROM ME WITHIN 24-48 HOURS. You may also want to consider these CISSP resources from Amazon.com

If you notice the list is in alphabetical order. There is no direct number designation for each domain. I also used the Shon Harris All-in-One book () primarily to do my review. Since I don’t have the book handy (it is stuck somewhere in storage), I went to Amazon and looked up the book and see if I can view the table of contents inside. The book is now on its fifth edition (CISSP All-in-One Exam Guide, Fifth Edition) and I know I have an older version. The oldest version I can find that has the Amazon Look Inside feature is the Third Edition. And voila! There it is the first domain discussed is Access Control and therefore making it Domain 1, right?

But wait, it also lists Telecommunications & Network Security fourth in the list, which means I am still up in smoke . I looked up the publication date of the third edition and it shows as September 15, 2005. I bought my book in 2003 and this means I have the older edition, which may have a different way of listing the domains. I can’t prove that since I don’t have the book and I don’t feel like diving into the abyss otherwise known as my storage, I just continued Googling for answers.

I looked up the Official CISSP book () that I have (Official (ISC)2 Guide to the CISSP CBK ((ISC)2 Press)) and it lists “Information Security Governance and Risk Management” as Domain 1, while “Access Control” is Domain 2. I really could care less, I already passed the exam, I already have 120 CPEs and I am on time on my membership payments to ISC2, so I am set to get my CISSP cert to be renewed by September this year. But this difference in numbering does bug me. Now I think about it, I did notice the numbering difference when I bought the Official CISSP book in 2006, I didn’t pay much attention to it for some reason since I was already deep into my studying of the Shon Harris book. What was I smoking? What was Ms. Harris smoking? Well to be quite sure, nothing.

As I did further Googling I landed into another SearchSecurity.com site. The site that started this little hubbub. And guess what I found?

Domain 1 is “Telecommunications & Network Security”, Domain 2 “Physical Security”…

Whut!?!

Yep, the site contradicted itself.

So a quick conclusion after all this little exercise in WTF, I concluded that OFFICIALLY there are 10 Domains in the CISSP Common Body of Knowledge. Which domain comes first, next and last, is NOT AN OFFICIAL RANKING OR NUMBERING. Don’t get too hung up on this while you are studying, you will not encounter a question in the exam that says, “In Domain 2 of the CBK…”, it will instead more than likely say, “In the Access Control Domain of the CBK…”

All that said, I wish you goodluck on the exam. If you are not taking the exam, thank you for reading . Happy weekend.

All-in-One is All You NeedFully revised for the latest exam release, this authoritative volume offers thorough coverage of all the material on the Certified Information Systems Security Professional (CISSP) exam. Written by a renowned security expert and CISSP, this guide features complete details on all 10 exam domains developed by the International Information Systems Security Certification Consortium (ISC²). Inside, you’ll find learning objectives at the beginning of each ch (more…)