Chapter 15 Network Management

Network management in simple terms is the assessing, monitoring and maintenance of all aspects of the network. A key element in being successfully is clear concise documentation. Some of the ways this is accomplished is through system logs, event logs, and through syslog.

Asset management is another important component in managing networks through identifying and tracking software and hardware. By doing so this simplifies maintaining and upgrading the system because you know what the system includes.

The chapter talks about many different types of upgrades. The following are just a few:

• Adding or Upgrading Equipment
• Cable upgrades
• Backbone upgrades 

All could be very expensive if not designed and implemented properly.

This chapter was an overview of many other concepts presented in the book. It stressed the importance of continual review and adjustment to the network. It explained the best ways to implement those changes.   

Chapter 14 Ensuring Integrity and Availability

This chapter is all about safeguarding your data and protecting your network. It discusses backup and recovery practices and as well as disaster recovery and contingency plans. It begins with two important concepts Integrity and availability. That is to say integrity refers to the soundness of a network’s programs, data, services, devices, and connections. Availability refers to how consistent and reliably a file or system can be accessed by authorized personnel. 

The text goes into discourse about Malware and the various types and characteristics. It follows-up with malware protection, anti-malware software and polices. If malware is unchecked it will wreak havoc on the system.

Safeguarding against malware is important; however another key component in maintaining the availability and integrity of data is fault tolerance. Fault tolerance is the capacity for a system to continue performing despite an unexpected software or hardware failure. Examples of potential areas that need to be monitored are Environment, Power, and Network design. Maintaining these areas is key in keeping fault tolerance to a minimum.

It is also important to have a backup strategy and storage plan. It could entail optical media, tape backups, external disk backup or network backups. This would be a good time to lay out a disaster recovery plan along with any contingencies. 

Chapter 13 Troubleshooting Network Problems

The chapter provides a logical and methodical way for troubleshooting network problems. This serves as a basic road map for identifying and resolving network issues. The process begins with identifying the problem and its symptoms. It is then important to determine the problems scope. Which is to say how many users are affected, a work group, a department, or the entire company? This data helps in determining the magnitude of the issue. The following bullet points provide a means to capture this information.  

•  Gather information
•  Identify symptoms
•  Question users
•  Determine if anything has changed

 After you have identified the scope of the problem it is then time to establish a theory of probable cause. An excellent way to learn more about the problem is to recreate the symptoms. One needs to be very careful in doing this because this could cause havoc for the system.  You must ask the obvious questions at this stage to help determine cause.   

Next you should test the theory to determine cause. It may be something as simple as a plug unplugged or a cable disconnected. The following bullet points provide a path.

•  If theory confirmed, determine next steps
•  If theory not confirmed, establish new theory or escalate

 At this juncture after you have analyzed the network and have identified the problem it’s time to establish action plan. In the action plan it should take into consideration what impact it will have on the users and network. After development you would implement the solution or escalate for further development. As part of the process the next step would be verify full functionality and implement preventative measures if applicable. And finally document findings, actions, outcomes.

The last part of the chapter spends time covering troubleshooting tools. It looks at tone generators and tone locator's, multimeters, cable continuity testers, cable performance testers, voltage event recorders. These are only a few.

The chapter had a lot of pictures, diagrams, and flow charts. It was very helpful in understanding the methodology of troubleshooting. 

Chapter 12 Voice and Video IP

This chapter is all about the variety of methods in which various signals travel for communication purposes. It begins with convergence, the use of multiply terms to refer to the same or similar technologies in common. For instant IP Telephony the use of any network private or public to carry voice signals using TCP/IP protocol. This technology is commonly known as VOIP. (Voice over IP) There are many different clients and network designs with VOIP. One of the benefits of using IP Telephony is it mobility. Analog VOIP needs to connect to an ATA (analog telephone adapter) which digitizes the data in order for transmitting purposes. It is much easier with Digital VOIP it typically connects to a PBX.

Videoconferencing and streaming video opens another avenue of communication. It allows multiply participates to communicate while viewing each other. This type of communicating depends upon the exchange of information between the components of a network system to establish connection.

The text provides some really good insight as to how all this different communication processes work. This synopsis only scratches the surface; the chapter goes into much more detail and covers many more topics.

Chapter 11 - Network Assessment

The threat of an outsider accessing an organization’s network via the internet and then stealing or destroying data is a real possibility today. Before spending any money or time on network security you should examine the network’s security risks. An organization should conduct a posture assessment which is a thorough examination of each aspect of the network to determine how it might be compromised. A security audit asses the security of your network.

Security risks come from all types of vulnerability weaknesses. When these weaknesses are taken advantage of it is known as exploiting. The following areas are of real concern:

• Risks Associated with People
• Risks Associated with Transmission and Hardware
• Risks Associated with Protocols and Software
• Risks Associated with Internet Access

 In an effort to help mitigate these risks an effective security policy goes a long way. It begins with identifying your security goals, risks, levels of authority, designated security coordinator, and team members’ responsibilities for each team member as well as responsibilities for each employee. It encompasses the following areas:

•  Security Policy Goals
• Security Policy Content
• Response Policy

 The chapter goes into myriad of topics discussing the various types of Physical Security, Security in Network Design, Network Operating System Security, Authentication Protocols, and Wireless Network Security. Each one these areas are delved into with much detail.

I found this chapter to be very helpful in reviewing some previous learned topics. It was presented in an organized and informative manner

Chapter 9 In-Depth TCP/IP Networking

In previous chapters we have learned that TCP/IP is a complex and highly customizable protocol suite. This chapter builds on these basic concepts, examining how TCP/IP based networks are designed and analyzed. It begins by explaining Subnetting. Subnetting separates a network into multiple defined segment or subnets. This might be done to achieve the following.

• Enhance security
• Improve performance
• Simply troubleshooting

 An internet gateway is a combination of software and hardware that enables two different network segments to exchange data. A gateway facilitates communication between two different networks of subnets. A public network is one that any user may access with little or no restrictions, whereas private network is a network whose access is restricted to only authorized clients.

All internet mail services operate on the same principles of mail delivery, storage, and pick-up though they may use different types of software to accomplish these functions. The following protocols achieve these tasks.

• Simple Mail Transfer Protocol (SMTP)
• Multipurpose Internet Mail Extension (MIME)
• Post Office Protocol (POP)
• Internet Message Access Protocol (IMAP)

The chapter covers the following utility programs that help analyze network traffic.

Ipconfig, Ifconfig, Nbtstat, Hostname, Host, Nslookup to name a few.

The text expands it discussion on the various topics mentioned in this Blog. Again the many pictures, diagrams, and charts helped in clarifying the concept.      

Chapter 8 Wireless Networking

The wireless spectrum is a continuum of the electromagnetic waves used for data and voice communication. Some important fundamentals about wireless networking are: antennas are used both for transmission and receiving wireless signals, wireless signals originate from electrical current, and the signal propagates through the air. Each type of wireless service requires a specifically designed antenna for that service. No matter what paths wireless signals take it is inevitable they will run into obstacles. There are many different frequencies which carry these signals. The wireless standards are noted in the chart below.

Some of the wireless pitfalls you want to avoid are:

• SSID mismatch – Wireless client must specify Service set identifier
• Incorrect encryption - Wireless client must be configured to the same type as access point
• Incorrect channel or frequency – Must use correct communication path
• Standard mismatch – Clients must match the correct standard
• Incorrect antenna – Must have correct antenna place in proper location
• Interference – Causes communication errors

With the proliferation of satellite technology and the reduction in cost this has made it possible to transmit consumer voice, video, music and data. Satellites in recent years have become a means of providing data services mobile clients. Most satellites circle the earth 22,300 miles above the equator in a geosynchronous orbit. This technology is well established and is the least expensive.

Once again this chapter provided a lot of good information about wireless networks. It explained the wireless spectrum, characteristics of wireless transmission, wireless LANs, implementing a WLAN, and wireless WANs. There are many diagrams charts and pictures which help in conveying the message of the material.