Chapter 15 Network Management
Network Management, here are some questions that may help improve Network Management Skills.
Documentation, are you doing it and is it up to date?
Baseline Measurements, what are you using for this now and how can you improve it?
Policies, Procedures, and Regulations, do you have one in place and when was the last time you reviewed it with users?
Fault and Performance Management what is your down time? How are you going to improve it?
Are you assessing and documenting the network’s status on an ongoing basis? What are the any daily routines? When was the last time you checked the event logs?
Performance management, how are you testing this?
Asset Management, can you identify and track hardware and software on your network?
Change Management, do you have the support of management, if so are you letting all users know of the changes and why?
Upgrade considerations, do you need to do it what is the compelling reason to do it? How much is it going to cost (labor, down time, etc.)?
NOS (Network Operating System) upgrades being the most critical upgrade type why are you changing?
Reversing a software upgrade, do you know how to do it prior to the upgrade?
Hardware and Physical Plant Changes, what is the compelling reason? How much is it going to cost (labor, down time, etc.)?
With network management if you are going to be a professional you need to continue to ask the obvious, WHY?
Thursday, December 3, 2009
Chapter 14 Ensuring Integrity and Availability
Chapter 14 Ensuring Integrity and Availability
CIA Triangle Confidentiality, Integrity and Availability: Three simple words with multiple meanings. Yet, one common thread unites them in the information environment to create a practical, organized approach to lowering the risks associated with managing data and systems.
Simply installing virus software is not enough you need to keep it up to date and educate your users. Watch and train users to notice and welcome them report the following symptoms:
•Unexplained file size increases
•Significant, unexplained system performance decline
•Unusual error messages
•Significant, unexpected system memory loss
•Periodic, unexpected rebooting
•Display quality fluctuations
When a user reports one of the symptoms or has heard of a virus ensure you don’t make them feel stupid for reporting otherwise they will not report it next time. As noted in security chapter 12 fifty perfect of your issues are human beings, I want the human factor on my side. Although you would like to tell them their latest issue was an “ID10T Error” hold your tongue and keyboard lashings. Mom always said, “If you don’t have something good about someone keep it to yourself”. Virus and Hoaxes users report use resources like SNOPES http://www.snopes.com/ or the knowledge database of the virus software you are running to verify legitimate viruses or Trojan viruses. A good rule of thumb/good practice is to check more than one resource to verify the information you are getting is correct. Once you have verified make sure to follow up with the user that has reported weather false or not and site your finds to them.
Fault-tolerant system goal is to prevent faults (malfunction) from progressing to failures (down) the following are items to insure you can reach your goal.
Physical environment, power techniques power backups (UPS's, Backup Generator, second power grid).
Topology and connectivity techniques dual internet/phone connections with failover techniques used in a router or firewall.
Server and storage techniques
Server mirroring is where you have an identical server in which one server continually duplicates the activities (data and transactions) of the main server.
Clustering servers is a technique that links multiple servers together to act as one server.
Storage RAID (Redundant Array of Independent [or Inexpensive] Disks) there are two differnet types hardware and software. Of the two hardware is faster and more reliable.
Different Raid Levels:
• RAIDZero means there is no redundancy the data is written across three drives. Fast however it is not fault tolerant.
• RAID level one disk mirroring the other automatically copying it to the second drive. SATA drives can write to both at the same time
• RAID Level one Disk duplexing two separate drives and two separate controllers.
• RAID Level 3 Disk Striping needs at least three drives data drive, data drive and a parity drive.
• RAID Level 5 -Disk Striping with Distributed Parity.
NAS (Network Attached Storage) is a specialized storage device group which provides centralized fault-tolerant data storage.
SANs (Storage Area Networks) Distinct networks of storage devices/servers that communicate directly with each other and other networks. Advantages are it is fast and fault tolerant. It uses special transmission methods using fiber-optic media and proprietary protocols.
Data backup Strategies:
Normal/Full: Backs up every file selected turns off A bit
Incremental: Backs up a bit files and turns off the A bit
Differential: Backs up a bit files - leaves A bit on
Copy: Backs up every file and leaves A bit on
Disaster Recovery Planning is a plan to ensure your organization is ready for a worst-case scenario disaster. Identifying and making people aware of who is on the disaster recovery team and the team members’ responsibilities. You will want contingency plans to restore and replace: Computer systems, Power, Telephony systems etc. To ensure your plan is solid stage an all systems to test (emergency outage) all systems to make sure they are working properly scheduled once a month, quarter, etc. Also when there are changes to hardware (Servers, Phones, Electrical, etc.) review your plan to ensure is has taken into account the changes.
CIA Triangle Confidentiality, Integrity and Availability: Three simple words with multiple meanings. Yet, one common thread unites them in the information environment to create a practical, organized approach to lowering the risks associated with managing data and systems.
Simply installing virus software is not enough you need to keep it up to date and educate your users. Watch and train users to notice and welcome them report the following symptoms:
•Unexplained file size increases
•Significant, unexplained system performance decline
•Unusual error messages
•Significant, unexpected system memory loss
•Periodic, unexpected rebooting
•Display quality fluctuations
When a user reports one of the symptoms or has heard of a virus ensure you don’t make them feel stupid for reporting otherwise they will not report it next time. As noted in security chapter 12 fifty perfect of your issues are human beings, I want the human factor on my side. Although you would like to tell them their latest issue was an “ID10T Error” hold your tongue and keyboard lashings. Mom always said, “If you don’t have something good about someone keep it to yourself”. Virus and Hoaxes users report use resources like SNOPES http://www.snopes.com/ or the knowledge database of the virus software you are running to verify legitimate viruses or Trojan viruses. A good rule of thumb/good practice is to check more than one resource to verify the information you are getting is correct. Once you have verified make sure to follow up with the user that has reported weather false or not and site your finds to them.
Fault-tolerant system goal is to prevent faults (malfunction) from progressing to failures (down) the following are items to insure you can reach your goal.
Physical environment, power techniques power backups (UPS's, Backup Generator, second power grid).
Topology and connectivity techniques dual internet/phone connections with failover techniques used in a router or firewall.
Server and storage techniques
Server mirroring is where you have an identical server in which one server continually duplicates the activities (data and transactions) of the main server.
Clustering servers is a technique that links multiple servers together to act as one server.
Storage RAID (Redundant Array of Independent [or Inexpensive] Disks) there are two differnet types hardware and software. Of the two hardware is faster and more reliable.
Different Raid Levels:
• RAIDZero means there is no redundancy the data is written across three drives. Fast however it is not fault tolerant.
• RAID level one disk mirroring the other automatically copying it to the second drive. SATA drives can write to both at the same time
• RAID Level one Disk duplexing two separate drives and two separate controllers.
• RAID Level 3 Disk Striping needs at least three drives data drive, data drive and a parity drive.
• RAID Level 5 -Disk Striping with Distributed Parity.
NAS (Network Attached Storage) is a specialized storage device group which provides centralized fault-tolerant data storage.
SANs (Storage Area Networks) Distinct networks of storage devices/servers that communicate directly with each other and other networks. Advantages are it is fast and fault tolerant. It uses special transmission methods using fiber-optic media and proprietary protocols.
Data backup Strategies:
Normal/Full: Backs up every file selected turns off A bit
Incremental: Backs up a bit files and turns off the A bit
Differential: Backs up a bit files - leaves A bit on
Copy: Backs up every file and leaves A bit on
Disaster Recovery Planning is a plan to ensure your organization is ready for a worst-case scenario disaster. Identifying and making people aware of who is on the disaster recovery team and the team members’ responsibilities. You will want contingency plans to restore and replace: Computer systems, Power, Telephony systems etc. To ensure your plan is solid stage an all systems to test (emergency outage) all systems to make sure they are working properly scheduled once a month, quarter, etc. Also when there are changes to hardware (Servers, Phones, Electrical, etc.) review your plan to ensure is has taken into account the changes.
Chapter 13 Troubleshooting Network Problems
Chapter 13 Troubleshooting Network Problems
If you see a bumper sticker that says, “User are losers” and you aren’t thinking about someone using drugs most likely you are a Network Administrator. Users come in many forms from button pushers, knob twisters or the indecisive user who doesn’t want to do anything that may screw up. With this in mind we need to look at every user issue as an opportunity to further the security policies, and the users’ basic understanding of the data …
Troubleshooting Methodology the following troubleshooting steps:
1. –Identify symptoms, problems
2. –Identify affected area
3. –Determine what has changed
4. –Establish most probable cause
5. –Determine if escalation necessary
6. –Create action plan, solution
7. –Implement solution, test result
8. –Identify results, effects
9. –Document solution, process
Troubleshooting Tools
Tone Generator and Tone Locator are used to located wiring from where begins to in telecommunications closet to where wire pair terminates.
Multimeters are used to tests cables for faults and measuring electric circuit characteristics (Resistance and voltage).
Cable Continuity Testers are used to tests whether cable carrying signal to destination. There are also Fiber optic continuity testers that issues light pulses onto the fiber cable to test.
Cable Performance Testers can do the same functions of a Cable Continuity tester however it is also do the following:
• Measure the distance to a connectivity device.
• Measure attenuation along a cable.
• Measure near-end cross talk between wires.
• Measure terminations resistance and impedance.
• Issue pass/fail ratings for Cat3, Cat 5, Cat 5e, Cat 6 or Cat 7 Standards.
• Store and print cable testing results or directly save data to a computer database.
• Graphically depict a cable’s attenuation and cross talk characteristics over the length of the cable.
Copper wire tester uses TDR(time domain reflectometers) where Fiber-optic connections testers use OTDRs (optical time domain reflectometers)
Voltage Event Recorders record voltage events any condition where voltage exceeds or drops below predefined levels and collects data about power quality.
Butt Set is a lineman’s handset, telephone test set giving the line man to butt into telephone conversations.
Network Monitors Software-based tools continually monitoring network traffic from server, workstation attached to network. It interprets up to Layer 3 can determine protocols passed by each frame however it cannot interpret frame data. To run it on the full network all Network adapters must support promiscuous mode. Common terms for abnormal data patterns, packets are local collisions, late collisions, runts, giants, jabber, negative frame sequence checks and ghosts.
Protocol Analyzers (network analyzer) captures traffic, analyzes frames typically to Layer 7. They have the same features as network monitor but it also generates traffic. Before using network monitor or protocol analyzer learn what network traffic normally looks like capturing data for time period on regular basis
Wireless Network Testers are tools containing wireless NICs, running wireless protocols.
If you see a bumper sticker that says, “User are losers” and you aren’t thinking about someone using drugs most likely you are a Network Administrator. Users come in many forms from button pushers, knob twisters or the indecisive user who doesn’t want to do anything that may screw up. With this in mind we need to look at every user issue as an opportunity to further the security policies, and the users’ basic understanding of the data …
Troubleshooting Methodology the following troubleshooting steps:
1. –Identify symptoms, problems
2. –Identify affected area
3. –Determine what has changed
4. –Establish most probable cause
5. –Determine if escalation necessary
6. –Create action plan, solution
7. –Implement solution, test result
8. –Identify results, effects
9. –Document solution, process
Troubleshooting Tools
Tone Generator and Tone Locator are used to located wiring from where begins to in telecommunications closet to where wire pair terminates.
Multimeters are used to tests cables for faults and measuring electric circuit characteristics (Resistance and voltage).
Cable Continuity Testers are used to tests whether cable carrying signal to destination. There are also Fiber optic continuity testers that issues light pulses onto the fiber cable to test.
Cable Performance Testers can do the same functions of a Cable Continuity tester however it is also do the following:
• Measure the distance to a connectivity device.
• Measure attenuation along a cable.
• Measure near-end cross talk between wires.
• Measure terminations resistance and impedance.
• Issue pass/fail ratings for Cat3, Cat 5, Cat 5e, Cat 6 or Cat 7 Standards.
• Store and print cable testing results or directly save data to a computer database.
• Graphically depict a cable’s attenuation and cross talk characteristics over the length of the cable.
Copper wire tester uses TDR(time domain reflectometers) where Fiber-optic connections testers use OTDRs (optical time domain reflectometers)
Voltage Event Recorders record voltage events any condition where voltage exceeds or drops below predefined levels and collects data about power quality.
Butt Set is a lineman’s handset, telephone test set giving the line man to butt into telephone conversations.
Network Monitors Software-based tools continually monitoring network traffic from server, workstation attached to network. It interprets up to Layer 3 can determine protocols passed by each frame however it cannot interpret frame data. To run it on the full network all Network adapters must support promiscuous mode. Common terms for abnormal data patterns, packets are local collisions, late collisions, runts, giants, jabber, negative frame sequence checks and ghosts.
Protocol Analyzers (network analyzer) captures traffic, analyzes frames typically to Layer 7. They have the same features as network monitor but it also generates traffic. Before using network monitor or protocol analyzer learn what network traffic normally looks like capturing data for time period on regular basis
Wireless Network Testers are tools containing wireless NICs, running wireless protocols.
Wednesday, December 2, 2009
Chapter 12 Network Security
Chapter 12 Network Security
As network technicians we all need to make sure we are aware of the threats out there and how to protect our systems from them. I find it amazing that half of the security breaches are human error, ignorance, omissions making the human factor the number one threat. Therefore the number one way to prevent it is the have a good security policy in place. Then educate our user populations on it making them aware of the threats/risks that come along with computers on a network attached to the internet. A good security policy should identify security goals, risks, authority levels, with a designated security coordinator, and team members. These need be reviewed and updated as security hardware and software change on our networks. Along with the security policy ensure strong password policies are in place and the frequency of having users changing their passwords on a regular 3 to 6 month basis.
The other fifty percent of threats and risks are associated with transmission and hardware the physical, data Link and network layers which require more technical sophistication.
Some of these risks are inherent in network hardware and design the following are examples: Network hubs broadcasting traffic over entire segment. Unused hub, switch, router, server ports not secured making private address availability to outside. Routers not properly configured to mask internal subnets or drop suspicious packets. Modems accept incoming calls access servers not secured or monitored.
Other are associated with protocols and software these include the Transport, Session, Presentation, and Application layers. Some of these risk are TCP/IP security flaws, NOS back doors, security flaws allowing server operators to exit to command prompt, leaving the administrators default security options (Factory defaults) on new hardware.
Others are associated with Internet access these can be the network security compromise more often “from the inside” web browsers permit scripts to access systems or users providing information to sites. Common Internet-related security issues are improperly configured firewalls; outsiders obtain internal IP addresses by IP spoofing, transmitting user IDs and passwords in plain text.
Another is associated with physical security locked doors restricting physical access network components at minimum. Only authorized personnel can access computer rooms, wiring closets switches, unattended logged in workstations, equipment rooms, entrance to the facility, and storage rooms.
Of course the more security conscience you need to be is determined the products or data your organization are producing or providing. If you are a manufacturer of automotive parts your security is going to be less robust compared to a banking institution or a credit card company. These are examples where you are going to use more secure encryption and authentication methods.
Encryption uses algorithms to scramble data then reads by algorithm reversal (decryption) these are a few types of encryption methods: Key Encryption weaves key into original data’s bits and generates a unique data block a key. AES (Advanced Encryption Standard) also a key encryption type that weaves 128, 160, 192, 256 bit keys through data multiple times and is a private key encryption so the sender must somehow share key with recipient. Public Key Encryption the data is encrypted using two keys a private key: user knows public key: anyone may request. PGP (Pretty Good Privacy) is a public key encryption which secures e-mail transmissions by verifying the sender authenticity, developed by Phil Zimmerman (1990s). SSL (Secure Sockets Layer) encrypts TCP/IP transmissions web pages, web form data entered into web forms. This is one you want to make sure your user population knows if they are going to be using the internet to procure over the internet via credit card. Here are a couple of more acronyms of encryption methods: SSH (Secure Shell), SCP (Secure CoPy), SFTP (Secure File Transfer Protocol), IPSec (Internet Protocol Security)
Authentication is the process of verifying a user’s credentials to grant user access to secured resources. The following are authentication protocols: PAP (Password Authentication Protocol),CHAP and MS-CHAP (Microsoft Challenge Authentication Protocol), EAP (Extensible Authentication Protocol), 802.1x (EAPoL), Kerberos.
As network technicians we all need to make sure we are aware of the threats out there and how to protect our systems from them. I find it amazing that half of the security breaches are human error, ignorance, omissions making the human factor the number one threat. Therefore the number one way to prevent it is the have a good security policy in place. Then educate our user populations on it making them aware of the threats/risks that come along with computers on a network attached to the internet. A good security policy should identify security goals, risks, authority levels, with a designated security coordinator, and team members. These need be reviewed and updated as security hardware and software change on our networks. Along with the security policy ensure strong password policies are in place and the frequency of having users changing their passwords on a regular 3 to 6 month basis.
The other fifty percent of threats and risks are associated with transmission and hardware the physical, data Link and network layers which require more technical sophistication.
Some of these risks are inherent in network hardware and design the following are examples: Network hubs broadcasting traffic over entire segment. Unused hub, switch, router, server ports not secured making private address availability to outside. Routers not properly configured to mask internal subnets or drop suspicious packets. Modems accept incoming calls access servers not secured or monitored.
Other are associated with protocols and software these include the Transport, Session, Presentation, and Application layers. Some of these risk are TCP/IP security flaws, NOS back doors, security flaws allowing server operators to exit to command prompt, leaving the administrators default security options (Factory defaults) on new hardware.
Others are associated with Internet access these can be the network security compromise more often “from the inside” web browsers permit scripts to access systems or users providing information to sites. Common Internet-related security issues are improperly configured firewalls; outsiders obtain internal IP addresses by IP spoofing, transmitting user IDs and passwords in plain text.
Another is associated with physical security locked doors restricting physical access network components at minimum. Only authorized personnel can access computer rooms, wiring closets switches, unattended logged in workstations, equipment rooms, entrance to the facility, and storage rooms.
Of course the more security conscience you need to be is determined the products or data your organization are producing or providing. If you are a manufacturer of automotive parts your security is going to be less robust compared to a banking institution or a credit card company. These are examples where you are going to use more secure encryption and authentication methods.
Encryption uses algorithms to scramble data then reads by algorithm reversal (decryption) these are a few types of encryption methods: Key Encryption weaves key into original data’s bits and generates a unique data block a key. AES (Advanced Encryption Standard) also a key encryption type that weaves 128, 160, 192, 256 bit keys through data multiple times and is a private key encryption so the sender must somehow share key with recipient. Public Key Encryption the data is encrypted using two keys a private key: user knows public key: anyone may request. PGP (Pretty Good Privacy) is a public key encryption which secures e-mail transmissions by verifying the sender authenticity, developed by Phil Zimmerman (1990s). SSL (Secure Sockets Layer) encrypts TCP/IP transmissions web pages, web form data entered into web forms. This is one you want to make sure your user population knows if they are going to be using the internet to procure over the internet via credit card. Here are a couple of more acronyms of encryption methods: SSH (Secure Shell), SCP (Secure CoPy), SFTP (Secure File Transfer Protocol), IPSec (Internet Protocol Security)
Authentication is the process of verifying a user’s credentials to grant user access to secured resources. The following are authentication protocols: PAP (Password Authentication Protocol),CHAP and MS-CHAP (Microsoft Challenge Authentication Protocol), EAP (Extensible Authentication Protocol), 802.1x (EAPoL), Kerberos.
Subscribe to:
Posts (Atom)
