Sections & Objectives
8.1 Computer to Network Connection
- Connect a computer to wired and wireless networks.
8.2 ISP Connection Technologies
- Explain the purpose and characteristics of ISP connection technologies.
8.3 Internet Technologies
- Explain Cloud concepts and networked-host services.
8.4 Common Preventive Maintenance Techniques Used for Networks
- Explain how to perform preventive maintenance on networks using common techniques.
8.5 Basic Troubleshooting Process for Networks
- Explain how to troubleshoot networks.
8.6 Chapter Summary
8.1 Computer to Network Connection
8.1.1 Networking Cards
A wired or wireless network interface card (NIC) is required to connect to the network.
After it is installed, IP settings must be configured either manually or dynamically.
You can also configure advanced settings, such as speed, duplex, Wake on LAN, and quality of service (QoS).
8.1.2 Wireless and Wired Router Configurations
To connect to a network, attach a straight-through Ethernet cable to the NIC port.
The other end connects to a router or to a telecommunications port that is wired so that data will reach the router.
For wireless connections, configure the router with the following:
- Network Mode (set the 802.11 standard)
- Network Name (SSID)
- Channel (important when there are multiple APs in the network)
- Wireless Security (should be WPA2)
8.1.3 Network Sharing
All Windows computers on a network must be part of either a domain or a workgroup.
Before computers can share resources, they must share the same domain name or workgroup name.
Mapping a local drive is a useful way to access a single file, specific folders, or an entire drive between different operating systems over a network.
Determine which resources will be shared over the network and the type of permissions users will have to the resources.
- Read – user can view data in files and run programs
- Change – user can add files and subfolders, change the data in files, and delete subfolders and files
- Full Control – user can change permissions of files and folders
8.1.4 Remote Connections
A virtual private network (VPN) is a private network that connects remote sites or users together over a public network, like the Internet.
When connected to the corporate private network, users become part of that network and have access to all services and resources as if they were physically connected to the corporate LAN.
Remote-access users must install the VPN client on their computers to form a secure connection with the corporate private network.
Remote Desktop allows technicians to view and control a computer from a remote location.
Remote Assistance allows technicians to assist customers with problems from a remote location.
8.2 ISP Connection Technologies
8.2.1 Broadband Technologies
- DSL uses the existing copper telephone lines to provide high-speed digital data communication between end users and telephone companies.
- Line of sight wireless Internet is an always-on service that uses radio signals for transmitting Internet access
- Cellular technology enables the transfer of voice, video, and data.
- Cable uses coaxial cable lines originally designed to carry cable television.
- Satellite is an alternative for customers who cannot get cable or DSL connections.
- Fiber broadband provides faster connection speeds and bandwidth than cable and DSL.
8.3 Internet Technologies
8.3.1 Data Centers and Cloud Computing
Data center is a data storage and processing facility run by an in-house IT department or leased offsite.
Cloud computing is an off-premise service that offers on-demand access to a shared pool of configurable computing resources.
The three main Cloud services models are:
- Software as a Service (SaaS)
- Platform as a Service (PaaS)
- Infrastructure as a Service (IaaS)
The four Cloud deployment models are:
- Private
- Public
- Community
- Hybrid
8.3.2 Networked Host Services
Hosts need a variety of services to securely access resources on the network and the Internet.
- Dynamic Host Configuration Protocol (DHCP) dynamically assigns IP addressing information to hosts.
- Domain Name Service (DNS) is the method computers use to translate domain names into IP addresses.
- Hypertext Transfer Protocol (HTTP) or the secure HTTP (HTTPS) are used by hosts to access web resources
- File Transfer Protocol (FTP) allows hosts to transfer data between a client and a server. Secure file transfer options include File Transfer Protocol Secure (FTPS), SSH File Transfer Protocol (SFTP), and Secure Copy (SCP)
- Simple Mail Transfer Protocol (SMTP), Post Office Protocol (POP), and Internet Message Access Protocol (IMAP) are the protocols hosts used to send and receive email.
Hosts need a variety of services to securely access resources on the network and the Internet.
- Print servers enable multiple computer users to access a single printer
- Proxy servers are popularly used to act as storage or cache for web pages that are frequently accessed by hosts on the internal network.
- AAA is a way to control who is permitted to access a network (authenticate), what they can do while they are there (authorize), and track what actions they perform while accessing the network (accounting).
- Intrusion Detection Systems (IDSs) passively monitor traffic on the network while Intrusion Prevention Systems (IPSs) can detect and immediately address a network problem.
- Universal Threat Management (UTM) include all the functionality of an IDS/IPS as well as stateful firewall services.
8.4 Common Preventive Maintenance Techniques Used for Networks
8.4.1 Network Maintenance
Preventive maintenance for networks includes the condition of cables, network devices, servers, and computers to make sure that they are kept clean and are in good working order.
You should develop a plan to perform scheduled maintenance and cleaning at regular intervals.
Inform the network administrator if you notice any of these issues to prevent unnecessary network downtime.
8.5 Basic Troubleshooting Process for Networks
8.5.1 Applying the Troubleshooting Process to Networks
Identify the Problem
- The first step in the troubleshooting process.
- A list of open and closed-ended questions is useful.
Establish a Theory of Probable Cause
- Based on the answers received, establish a theory probable cause.
- A list of common problems can be useful.
Test the Theory to Determine Cause
- Test your theories to determine the cause of the problem.
- A list of quick procedures to common problems can help.
Establish a Plan of Action to Resolve the Problem and Implement the Solution
- A plan of action is needed to solve the problem and implement a permanent solution.
Verify Full Network Functionality and Implement Preventive Measures
- It is important to perform a full network check.
- If applicable, implement preventive measures to avoid future problem recurrences.
Document Findings, Actions and Outcomes
- Findings, repairs and notes should be documented.
- This log can be helpful for future reference.
8.5.2 Common Problems and Solutions for Networks
Network problems can be attributed to hardware, software, or configuration issues
Common networking problems include:
- Network cables are damaged or unplugged.
- Legitimate users are denied remote access.
- Device lacks sufficient addressing information.
- Users cannot access the Internet.
- User cannot map a drive or share a folder on the network.
8.6 Chapter Summary
This chapter introduced the operation of computer networks. The following concepts from this chapter are important to remember:
- Each device must have appropriate addressing in order to access network resources.
- Wired devices are attached to a network using an Ethernet cable. Wireless devices authenticate and associate with a wireless access point.
- Mapping a local drive is a useful way to access a single file, specific folders, or an entire drive between different operating systems over a network.
- VPNs allow private connections over public networks.
- Remote Desktop allows network administrators to remotely control a computer.
- Examples of broadband technologies include DSL, cable, and cellular.
- Data centers are facilities that provide data storage services.
- Cloud computing use data centers to provide cloud services in a variety of deployment models.
- Networked host services include DHCP, DNS, HTTP, FTP, SMTP, proxies, AAA, IPSs, and UTMs.
- Networks require a systematic preventive maintenance and troubleshooting methodology.