Document

Transcript Document

Network Technology Associate v2.0

Lesson 1: Introduction to Networking

Lesson 1 Objectives

• Define telephony and convergence networking • Identify network topologies • Describe the OSI/RM and the packet-creation process • Define the nature and purpose of TCP/IP • Define LANs and WANs • Describe server-based and peer-to-peer networks • Describe a Network Operations Center (NOC) • Describe peer-to-peer and server-based networks • Distinguish between distributed architectures and database models Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Telephony and Convergence Networking

• PSTN – still an integral part of the Internet infrastructure because it furnishes most of the long-distance connections • Voice over IP (VoIP) – voice transmissions are delivered in digital form as packets of data using an Internet connection and hardware or software installed on personal computers • Unified communications enable voice to be converted into text, and vice versa • Presencing – the ability for devices to automatically track and report your location and availability Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Mainframes

• Mainframe (centralized) computing provided the first practical network solution – Retrieving information from mainframes – Mainframe liabilities – The future of mainframes – Mainframes and cloud computing / Software as a Service (SaaS) Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Mainframe Networking Model

Client/Server Model

(cont'd)

Network Operations Center (NOC)

• A specific location from which a network is managed, monitored and maintained • Central point for network maintenance and troubleshooting • Generally includes multiple, redundant network connections and redundant power supplies • Many have dedicated phone lines from a separate provider and mobile phones to ensure communication in an emergency Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Networking Categories

• Bus • Star • Ring • Hybrid • Mesh

Network Topologies

Network Operating Systems

OSI Reference Model

• Defined by the International Organization for Standardization (ISO) in 1983 • Gives developers universal concepts so they can develop and perfect protocols that can work with operating system and network products developed by other vendors • Explains the framework used to connect heterogeneous systems • Describes the process of packet creation (how the layers communicate) Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

OSI Model Layers

Packets

Packet Creation

( Adding Headers )

OSI/RM Protocol Examples

• Application layer – SMTP, DNS, FTP, HTTP, SMB, NFS • Transport layer – TCP • Network layer – IP • Data link layer – Ethernet, Token Ring Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Major Networking Protocols

Transmission Control Protocol / Internet Protocol (TCP / IP)

• Transmission Control Protocol / Internet Protocol • A collection of protocols – TCP – IP – User Datagram Protocol (UDP) • An open standard Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Binding Protocols

Local Area Networks (LANs)

Wide Area Networks (WANs)

Internet Exchange Point (IXP)

Lesson 1 Summary

         Define telephony and convergence networking Identify network topologies Describe the OSI/RM and the packet-creation process Define the nature and purpose of TCP/IP Define LANs and WANs Describe server-based and peer-to-peer networks Describe a Network Operations Center (NOC) Describe peer-to-peer and server-based networks Distinguish between distributed architectures and database models Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Lesson 2: Networking Components and Standards

Lesson 2 Objectives

• Identify common network components • Identify transmission media and types • Define wireless network technologies • Describe IEEE LAN standards • Describe T and E carriers • Identify the requirements and benefits of virtualization Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Common Network Components

• Network Interface Cards (NICs) • Hubs • Bridges • Routers • Switches • Channel Service Unit / Data Service Unit (CSU/DSU) • Modems • Firewalls Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Transmission Media

Wireless Network Technologies

• Wireless communications use spread spectrum technologies – OFDM – DSSS – MIMO • Wireless networking modes – Ad-hoc – Infrastructure • Wireless access point (AP) • Wireless AP security features – Wired Equivalent Privacy (WEP) – Wi-Fi Protected Access 2 (WPA2) – MAC address filtering Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Wireless Network Technologies

(cont'd)

Transmission Types

IEEE LAN Standards

• IEEE 802.2

• Ethernet/IEEE 802.3

• IEEE 802.3u — Fast Ethernet • IEEE 802.3z and 802.3ab — Gigabit Ethernet • IEEE 802.3ae — 10-Gigabit Ethernet • IEEE 802.5 — Token Ring • IEEE 802.11 — Wireless Ethernet Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

T-Carrier System

T Carrier

T1 T2 T3 T4 T5

Data Transfer Rate

1.544 Mbps 6.312 Mbps 44.736 Mbps 274.176 Mbps 400.352 Mbps

E-Carrier System

E-Carrier Data Transfer Rate

E1 E2 E3 E4 E5 2.048 Mbps 8.448 Mbps 34.368 Mbps 139.264 Mbps 565.148 Mbps

Virtualization

• Virtualization allows you to run multiple virtual operating systems and applications on a single physical computer – VMware – Parallels – VirtualBox • Requirements for virtualization • Benefits of virtualization Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Lesson 2 Summary

 Identify common network components  Identify transmission media and types  Define wireless network technologies  Describe IEEE LAN standards   Describe T and E carriers Identify the requirements and benefits of virtualization Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Lesson 3: Connecting to the Internet

Lesson 3 Objectives

• Identify mobile devices and operating systems • Define the nature and purpose of TCP/IP • Explain the routing process • Discuss routing protocols • Describe port numbers and their functions • Compare and contrast IPv4 and IPv6 • Explain IP addressing, subnet masks, subnet prefix length, and the use of public and private IP addresses • Define the TCP/IP properties needed to configure a typical workstation • Describe various diagnostic tools for troubleshooting TCP/IP networks Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Mobile Computing

Mobile Devices and Cloud Computing

Configuring a Wireless Network

1. Plug in the wireless AP 2. Configure the wireless AP's SSID, encryption level and shared key 3. Insert the wireless NIC into the computer 4. Choose a networking protocol and configure the protocol for each client 5. Configure each computer's wireless NIC to use the wireless AP 6. Troubleshoot the connection 7. Configure additional security features 8. Plug the wireless AP into a wired network (optional) Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Fourth-Generation (4G) Wireless

TCP/IP

Internet Architecture

Application Layer Transport Layer Internet Layer Network Access Layer

Internet Protocols

Demultiplexing

IGMP Telnet FTP TCP TFTP UDP SNMP ICMP IP RARP ARP ETHERNET

Introduction to Routing

Routing Protocols

Port Numbers

• 16-bit integer value that identifies a communication channel to a specific user process – FTP = Port 21 – HTTP = Port 80 – DNS = Port 53 – SMTP = Port 25 Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Internet Protocol Version 4 (IPv4)

• Was the primary Internet address system until advent of IPv6 • IPv4 addresses are now depleted • Subnet mask – Distinguishes the network and host portions of an IPv4 address – Specifies whether a destination address is local or remote Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Internet Protocol Version 4 (IPv4)

field1.

field2

.field3.field4

Internet Protocol Version 6 (IPv6)

• Shortcomings of IPv4 – Limited address space – Lack of security – Speed problems – Configuration problems • Strengths of IPv6 – More efficient and requires less administrative overhead than IPv4 – Provides a practically unlimited number of IP addresses – Less dependent on routers Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Internet Protocol Version 6 (IPv6)

Configuring TCP/IP

Diagnostic Tools for Internet Troubleshooting

• • • • •

ping tracert route netstat ipconfig

and

traceroute

— Windows • •

ifconfig

— UNIX/Linux

arp

Troubleshooting Considerations

Lesson 3 Summary

       Identify mobile devices and operating systems Define the nature and purpose of TCP/IP Explain the routing process Discuss routing protocols Describe port numbers and their functions Compare and contrast IPv4 and IPv6 Explain IP addressing, subnet masks, subnet prefix length, and the use of public and private IP addresses   Define the TCP/IP properties needed to configure a typical workstation Describe various diagnostic tools for troubleshooting TCP/IP networks Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Lesson 4: Internet Services

Lesson 4 Objectives

• Identify and describe the functions and features of various Internet servers • Identify the functions and features of Internet-based services • Identify industry-standard Internet servers • Explain the advantages and disadvantages of cloud-based services • Discuss the uses and benefits of a Content Management System (CMS) Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Cloud Services

• Service provider runs services from remote data center • Advantages – Elimination of equipment, purchasing and maintenance – Cost savings – Industry job growth • Disadvantages – Security – Expectations – Failures Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Cloud Services

(cont’d)

• Three flavors of cloud computing

• File • Print • HTTP • Proxy • Mail

Internet Servers

• Mailing list • Social networking • DNS • FTP • Instant messaging • Certificate • Directory • Fax • Transaction

File and Print Servers

• File servers — network servers that store data files and programs that can be shared by network users • Print servers — network servers that allow multiple users to send print jobs to the same physical printer • Line Printer/Line Printer Daemon (LPR/LPD) — printing protocol in UNIX that allows users to submit print jobs to network printers Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

HTTP Servers

• The Web — a collection of computer systems running the HTTP service • Web server — has access to HTML documents that are returned to a client in response to a request • Common Web servers – Apache server – Microsoft Internet Information Services (IIS) – Nginx Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Database Servers

• Database — a file that stores information in a series of tables and columns • Relational database — a database consisting of two or more tables related by a common field • Database server — a server that presents relational databases and makes it possible for remote individuals to access the data • All database servers use SQL to create, maintain and query databases Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Social Networking

• LAMP (Linux, Apache, MySQL, PHP): – Linux — operating system – Apache — Web server – MySQL — relational database management system – PHP —object-oriented scripting language (Perl or Python can also be used) Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Proxy Servers

• Proxy server — an intermediary between a network host and other hosts outside the network • Proxy servers: – Provide enhanced security – Manage TCP/IP addresses – Speed Internet access by caching Web documents – Replace network IP address with another, contingent address Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Mail Servers

• Mail servers store/forward e-mail messages using several protocols: – SMTP — used to send messages – POP3 — used to store and forward messages (forces a user to download messages before managing them) – IMAP — used to store and forward messages (allows a user to browse and manage messages remotely) • MIME is used to transmit files with e-mail Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Instant Messaging (IM)

• Instant messaging runs on a typical server installation • Use IM to: – Type and view messages sent to one or more recipients – View the responses immediately • IMs can be sent only to contacts who are currently online Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Mailing List Servers

• A mailing list server forwards an e-mail message to every member on a distribution list • Mailing List Manager (MLM) — the interface that allows you to configure a mailing list server • Public vs. private mailing lists • Examples of public mailing lists: – LISTSERV – Majordomo Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Mailing List Servers

(cont'd)

DNS Servers

• DNS — mechanism used on the Internet to translate host computer names into IP addresses – www.CIWcertified.com = http://72.44.192.233

DNS Servers

(cont'd)

• DNS hierarchy – Root-level domain — the top of the hierarchy that contains entries for each top-level domain – Top-level domain — consists of categories found at the end of domain names – Second-level domain — includes the businesses and institutions that register their domain names with the top-level domains Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

DNS Servers

(cont'd)

• DNS components – Name server — server that supports name-to address translation and runs the DNS service – Name resolver — software that uses the services of one or more DNS servers to resolve an unknown request • DNS records — entries in DNS database that provide additional routing and resolution information Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

DNS Servers

(cont'd)

DNS Servers

(cont'd)

Domain name space

DNS Servers

(cont'd)

•

nslookup

– Used to query Internet domain name servers to learn name-to-IP-address mappings – Example of nslookup one-time command: •

nslookup www.CIWcertified.com

– Used interactively by typing: •

nslookup

FTP Servers

• File Transfer Protocol (FTP) allows the transfer of large files between file servers in real time • Files of 2 MB or greater should be transferred by means of FTP • Sending files by means of FTP is faster than with e mail and HTTP Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Certificate Servers

• A certificate server validates, or certifies, encryption keys • Keys — strings of text generated from encryption algorithms that allow you to secure communications for a company or group of users Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Directory Servers

• Identify all resources on a network, then make them available to authenticated users • Enable a company to reuse information in its directory • Reduce/eliminate re-entry of user information for applications that require it • Help administrators manage applications and users • Help users locate other users or e-mail addresses • Locate and manage all company accounts • Allow users inside and outside the network to use the service • Maintain a single database of e-mail contacts Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Fax and Transaction Servers

• Fax servers – Provide a centrally located fax system – Consist of a bank of fax/modems • Transaction servers – Guarantee that all required databases are updated when a transaction takes place Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Choosing Web Server Products

• Apache Web server – Used by almost two-thirds of all Web sites – Supports UNIX and Windows – Available free of charge • Microsoft IIS – Includes HTTP, FTP, NNTP, SMTP, certificate, ASP, index (catalog) and transaction services – Allows you to use a remote server to store and retrieve files Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Choosing Web Server Products

(cont'd)

• Sun Java System Web Servers – Support many platforms, including Sun Solaris, Windows, Linux, AIX and HP-UX – Support JavaServer Pages (JSP) technology and Java servlets – Can use Java to connect to databases – Can implement other server-side scripting applications Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Choosing Web Server Products

(cont'd)

• Java software and Web servers – Java servlet — Java code that is compiled and runs solely on Web servers – Servlets allow: • Chaining • Connections to databases • Near-universal support on systems Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Content Management System (CMS)

• CMS – allows you to easily create, store and track all documents and information produced by an organization • Benefits – Centralized management of content – Ability to reuse content – Increased collaboration Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Content Management System (CMS)

(cont'd)

• Common CMS Services – Role management – Permission management – Content publication – Content editing – Version control – Indexing and searching – Caching and replication – Simplified backup – Syndication Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Content Management System (CMS)

(cont'd)

• CMS as a workflow management tool – Helps managers and executives ensure that users properly submit and manage content • CMS requirements analysis – Number of users – Projected server load – Storage capacity Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Content Management System (CMS)

(cont'd)

• Managing a CMS – Workflow management – Content acquisition – Standard tagging – Taxonomic and social tagging – Template creation and management – Localization – Personalization and portals Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Content Management System (CMS)

(cont'd)

Content Management System (CMS)

(cont'd)

Lesson 4 Summary

     Identify and describe the functions and features of various Internet servers Identify the functions and features of Internet-based services Identify industry-standard Internet servers Explain the advantages and disadvantages of cloud-based services Discuss the uses and benefits of a Content Management System (CMS) Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Lesson 5: Hardware and Device Connectivity

Lesson 5 Objectives

• Identify the functions of motherboards, storage devices and optical discs • Connect common peripherals • Describe the importance of obtaining proper software licensing • Identify how to partition disks and prepare logical drives • Describe the characteristics of file system types Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Lesson 5 Objectives

(cont'd)

• Describe the uses of file system management tools • Identify and suggest corrective measures for operating system boot problems and application failures • Identify methods to remotely manage and troubleshoot workstations • Back up and restore files Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Motherboard

• Main circuit board in a computer • Must be securely fastened to system chassis • Should never touch anything metal, except through proper connections • Most motherboard components are soldered on and no longer replaceable • If components fail (except for memory and the microprocessor), the entire motherboard needs to be replaced Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

IRQs, I/O Addresses and DMA

• Interrupt requests (IRQs) — hardware lines used to identify when a device wants to communicate with the processor – Example: When a printer has finished printing, it sends an interrupt signal to the computer so the computer can decide what to process next • Input/output (I/O) address — memory location that allows the system processor and system devices to communicate • Direct memory access (DMA) — allows a device to access system memory directly, bypassing the processor Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Electronic Communication

• Binary numbering – Converting decimal values into binary – Bytes and bits • Hexadecimal numbering – Converting from hexadecimal into binary and decimal – Converting from binary into hexadecimal • ASCII Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Communication Basics

(cont'd)

Storage Devices

• To communicate with a motherboard, mass storage devices need to be connected to the motherboard through an interface • Four most common interfaces are: – SATA / eSATA – SCSI – USB – Memory card reader Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Serial ATA (SATA)

• SATA is currently the

de facto

standard for PC-based drives • SATA devices are connected using a cable that can transfer 3 Gbps (SATA version 1) or 6 Gbps (SATA version 2) Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Small Computer System Interface (SCSI)

• With SCSI, multiple devices can be connected to a single controller in a daisy chain configuration • You can attach as many as 127 internal or external SCSI devices to a single controller • SCSI daisy chain must be terminated at both ends and only at the ends Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Universal Serial Bus (USB)

• Many external hard drives connect to computers using a USB connection • USB flash drives are replacing DVD/CD drives USB flash drive Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Memory Card Reader

• Used to read and write data on memory cards (e.g., Secure Digital (SD) cards and Memory Sticks) • Do not store information Internal multi-card reader Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Memory Card Reader

(cont’d)

Network Interface Card (NIC)

• Each network device must have a NIC (or network adapter card) • The network adapter makes the physical connection between the device and the network cabling • The network adapter converts the data from the computer into a format appropriate for transmission over the network • Transceiver — the network adapter component that handles data transmission Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Optical Discs

Compact Disc —Read-Only Memory (CD-ROM)

• CD-ROM — an optical storage device from which data can be read only • CD-ROM drives use common mass storage interfaces • Writable CD devices allow you to create, or "burn," your own data and audio CDs – CD-R (CD-recordable) — write data once – CD-RW (CD-rewritable) — write data multiple times Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Digital Video Disc (DVD)

• DVD — optical storage device from which data can be read only • DVDs are similar to CD-ROMs but have higher storage capacity – Initial DVD standard provided 4.7 GB of storage capacity – Current DVD standards support dual-layer discs with a storage capacity of 8.5 GB – Double-sided disc standard supports 9.4 GB when writing to one side or 17 GB total when writing to both sides Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Blu-Ray Discs (BDs)

• High-definition optical disc storage medium that is designed to be the successor to DVDs • Single-layer Blu-ray Discs can hold up to 25 GB of data • Dual-layer Blu-ray Discs can hold up to 50 GB of data • BD-R — a write-once format • BD-RE — a rewritable format Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Optical Disc Drive Maintenance

• Keep the drives closed when they are not in use, and check all media for foreign matter before inserting into the drive • Optical discs should be handled only by the edges • Avoid scratching the disc surface • Never directly touch or try to manually clean the laser • Brush away and vacuum accumulated dust • Manually eject a stuck disc by inserting a wire into the small hole on the face of the drive, then pressing hard until the disc is ejected Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Device Connectivity

• Peripheral ports • PS/2-style connectors • Traditional serial ports and parallel ports have been replaced almost entirely by USB ports • Standard port use • Troubleshooting port and cabling problems Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

HDMI and DVI Connections

• Transmit high-definition digital video and high resolution digital audio data • Consist of 19 wires wrapped in a single cable • Carry bandwidth of up to 5 Gbps • Preserve the source digital signal by eliminating the digital-to-analog-to-digital conversion • Should not run longer than 15 feet (5 meters) to prevent signal degradation Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

System Management

• Obtaining proper operating system and software licensing • Identifying common file systems • Using common file system management tools • Using utilities to perform maintenance and recover from application failures • Troubleshooting software, including identifying common boot problems • Identifying ways to remotely manage and troubleshoot workstations Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Software Licensing

• When you purchase software, you are purchasing the right to use the software under certain restrictions • These restrictions are outlined in the license agreement • When you load software, the license agreement typically displays during the installation process • You must indicate that you have read and understood the agreement before the installation procedure will allow you to continue Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Software Licensing

(cont'd)

• Apart from legal consequences, using unlicensed software can also mean: – No documentation – No warranties – No technical product support – Greater exposure to software viruses, corrupt discs or otherwise defective software – Ineligibility for software upgrades Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Partitions and Logical Drives

• When installing an operating system on a new computer or after recovering from a hard disk failure, prepare the hard disk for use by: – Partitioning the hard disk – Creating logical drives – Formatting logical drives Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Disk Partitioning

• Partition disks to divide total storage space • Primary partition — the system’s boot drive, used for system startup • Extended partition — the remaining drive space after you create the primary partition Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Logical Disk Drives

• A disk partition must be assigned a logical drive identifier • A primary partition is treated as a single logical drive • An extended partition can be divided into multiple logical drives (Drives D and E in figure) Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Logical Drive Format

• Low-level format – Prepares the hard disk before disk partitions can be defined – Primarily the responsibility of the hard disk manufacturer • High-level format – Logical drive formatting that prepares the drive for use by the operating system – Creates the file system root directory and the files used to track disk space use Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

File Systems

• Primary partitions and logical drives must be formatted so the operating system can use them • Formatting creates the file system by adding information about how files should be stored on the drive to organize and manage disk storage • File system types include: – FAT32 and NTFS (Windows) – Ext and Reiser (Linux) Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

File and Directory Permissions

• NTFS allows you to set permission bits on system resources • In NTFS, you can protect files so that only certain users or groups of users can read them • Concerns – If permissions are applied improperly, users may take security for granted – Improperly set permissions can disrupt an operating system Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Convert Utility

• Information about the files on an NTFS volume and their attributes is stored in the master file table (MFT) • Convert utility — used to convert a partition or logical drive from FAT32 to NTFS convert drive /FS:NTFS [/v] Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Preventive Maintenance

• Preventive maintenance — Avoid component failures by maintaining them properly at all times • Planned maintenance — Schedule preventive maintenance tasks to occur at regular intervals • Device cleaning – Remove accumulated dust Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Disk Defragmenter Utility

• As files are created and deleted, a partition can become severely fragmented • Fragmented files are no longer located in contiguous clusters • You can use the Disk Defragmenter utility to defragment hard disks and put files back together in a contiguous format Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Chkdsk Utility

• You can use the Chkdsk utility in Windows to: – Create and display a status report for a disk based on its file system – List and correct errors on the disk – Display the status of the disk in the current drive Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Disk Cleanup Utility

• Use the Disk Cleanup utility to recover the disk space used by: – Temporary files – Unused applications – Files in the Recycle Bin – Files you downloaded as part of Web pages – Files created when Chkdsk attempted to recover lost file fragments Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Backup and Restore Utilities

• Keep a current backup of all data files to ensure that data can be recovered if a hard drive fails • When you back up data, you store copies of folders and files to a source other than your computer's hard disk • You restore data when you need to access the backed up data Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Uninterruptible Power Supply (UPS)

• Allows your computer to keep running for at least a short time when the primary power source is lost • Uses a battery to maintain power during an outage • You must choose which computers to protect with UPS Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Software Troubleshooting

• Software troubleshooting refers to anything other than problems caused by system hardware • Software problems can be caused by: – Bugs – Corrupted files – Incompatibilities – Virus infections Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Operating System Boot Problems

• Error: No operating system – Bad or missing command interpreter – Missing ntldr (Windows) – Kernel not available (Linux) – Operating system files missing – Hard disk or controller failure Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Blue Screen of Death (BSOD)

• Blue screen that indicates that a critical operating system failure has occurred during startup • To troubleshoot: – Restart the system in Safe mode and use the Last Known Good Configuration option – Reinstall the operating system – Attempt to diagnose the problem by parsing the dump file Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

System Lockup

• Lockup causes: – Applications that are incompatible with the operating system or with a hardware component – IRQ conflicts – Related problems that you may be able to find in the system log file • Power down your system by manually pressing and holding down the power key for five seconds Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Application Failures

• Application failure causes: – Low system RAM – Current logon environment crashes – Improper permissions – Improper system resolution or color levels • View the system log – Windows Event Viewer – Linux/UNIX "messages" Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Application Failures

(cont'd)

• Windows protection error causes: – Device drivers that may not be written specifically for your operating system – Applications or utilities that attempt to bypass the operating system and directly access local system hardware • Application installation and loading failures: – Application will not load into memory – Application can cause an illegal operation, resulting in the blue screen of death – Application may not install at all Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Lesson 5 Summary

 Identify the functions of motherboards, storage devices and optical discs  Connect common peripherals  Describe the importance of obtaining proper software licensing  Identify how to partition disks and prepare logical drives  Describe the characteristics of file system types Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Lesson 5 Summary

(cont'd)

  Describe the uses of file system management tools Identify and suggest corrective measures for operating system boot problems and application failures  Identify methods to remotely manage and troubleshoot workstations  Back up and restore files Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Lesson 6: Network and Cloud Security Risks

Lesson 6 Objectives

• Identify various network attacks and ways to defeat them • Describe authentication principles • Explain the three major types of encryption • Describe security zones • Describe the function of a VPN • Describe security audit principles • Discuss mobile device management (MDM) • Identify BYOD policies • Identify security threats to cloud-based networks • Identify ways to avoid anti-social activity (e.g., online stalking, cyberbullying) Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Defining Security

• Security — a set of procedures designed to protect transmitted and stored information, as well as network resources • Security administrators must determine which people can take appropriate actions on specific items at the appropriate time Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Bring Your Own Device (BYOD)

• 70 percent of employees bring personal mobile devices to work • BYOD policies limit vulnerabilities – Acceptable Use – Scope of Control – Device Scope – Enforcement – Support Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Bring Your Own Device (BYOD)

(cont’d)

Cloud Security Threats

Cloud Disaster Recovery

• Plan for failure • Do not get locked into a contract • Review your SLA • Create redundancy • Continuous data protection (CDP) — saves every change made to computer data Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Malware

• Virus — code that causes damage to systems • Virus types – Macro/script – File infecting – Boot sector – Stealth – Polymorphic – Retro • Worm — similar to virus but automatically replicates Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Overview of Network Attack Types

• Spoofing • Man in the middle • DOS • Distributed DOS • Brute force • Dictionary • Back door • Buffer overflow • Trojan • Social engineering To avoid attacks: • Install stable updates • • • Use encryption Be suspicious of information requests Remain informed Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Phishing, Pharming and Anti-Phishing Software

• Phishing – a form of social engineering that attempts to gather personal and financial information from unsuspecting victims by sending e-mail and luring the user to a legitimate-looking site, then requesting passwords, accounts numbers, etc.

• Pharming – the act of installing malicious code on personal computers or servers that redirects Internet traffic from a legitimate Web site to an identical-looking bogus Web site • Anti-phishing software – program designed to identify phishing content contained in Web sites and e-mail messages Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Defeating Network Attacks

Authentication

• Three authentication methods – What you know – What you have – Who you are • Passwords – Strong passwords – Age passwords appropriately • Account lockout — disables accounts after a given number of invalid passwords have been entered • Account reset — enables you to choose whether accounts reset automatically after a given interval Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Authentication

(cont'd)

• Managing passwords – Use password manager software to help store and manage your passwords – Example: KeePass • Password generators – Algorithms that receive input from a random or pseudo-random number generator and then automatically generate a password Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Digital Certificates

• Provide authoritative identification • Verify the sender's identity • Use the X.509 standard • Are used for non-repudiation • Contain digital signatures – Certificate authority (CA) Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Public Key Infrastructure (PKI)

• PKI CA servers: – Are repositories for managing digital certificates – Enable the secure creation and management of digital certificates – Provide the ability to revoke an invalid key • If you need a certificate for a server, use PKI Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Encryption

• The primary means to ensure privacy across the enterprise • Symmetric-key encryption – One key to encrypt and decrypt – All parties must know and trust one another • Symmetric algorithms – DES – Triple DES – AES Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Encryption

(cont'd)

• Asymmetric-key encryption – Uses a key pair (one public, one private) – Used to create a digital signature • Asymmetric algorithms – RSA – DSA Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Encryption

(cont'd)

• Hash encryption – Uses a hash table that contains a hash function – Used for information that will not be decrypted or read • Hash algorithms – SHA Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Encryption

(cont'd)

• Pretty Good Privacy (PGP) — uses a combination of the three encryption types • GNU Privacy Guard (GPG) — the open-source version of PGP • PGP and GPG: – Use symmetric-key encryption to scramble the original message you want to send – Use asymmetric-key encryption to encrypt only the symmetric key you just used – Use hash encryption to "sign" the message and ensure that no one can tamper with it Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Firewalls

• A firewall is a secure computer system placed between a trusted network and an untrusted one, such as the Internet – The most common location for a firewall is between a corporate LAN and the Internet • Allows users from a protected network to access a public network while simultaneously making the protected company's products and services available to the public Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Internal and Personal Firewalls

• Internal firewall — resides inside your company's internal network – Internal firewalls can: • Protect sensitive systems • Isolate networks that still need Internet connectivity but which use software that may cause problems with other company resources • Personal firewall — offers protection for an individual system Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Packet Filtering

• Packet filter — inspects each packet for predefined content • Packet filters filter data based on the following fields in the packet: – Source IP address – Destination IP address – TCP/UDP source port – TCP/UDP destination port Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Proxy Servers

• A proxy server replaces the network IP address with a single IP address • Provides the following services: – Hiding of network resources – Logging – Caching • Application-level gateway — a proxy between the Internet and your internal system at the application level • Most firewalls are combinations of packet filtering and application-level gateways Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Network Address Translation (NAT)

• The practice of hiding internal IP addresses from the external network • Two ways to provide NAT – Configure masquerading on a packet-filtering firewall – Use a proxy server to conduct requests on behalf of internal hosts Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Accessing Internet Services

• If Internet access is required and a network is located behind a proxy server or firewall, you may have problems accessing Internet services that use ports other than common ports • To avoid these problems: – Make sure the network has access to all Internet-related protocols used by the company – Make sure that the IP addresses assigned to the computers in your network have permission to access the Internet Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Security Zones

• Demilitarized zone (DMZ) — a mini-network that resides between a company's internal network and the external network • Intranet — a security zone available only to authorized organization employees • Extranet — a private network that allows selected access to outsiders only after they provide authentication information • Virtual LAN (VLAN) — a logical grouping of hosts, generally not implemented by a firewall Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Virtual Private Network (VPN)

• A technique that allows secure communication across long distances, usually for a company extranet • In a VPN, the Internet is often the corporate network backbone • Appropriate for any organization requiring secure external access to internal resources • All VPNs are tunneling protocols — encryption occurs at the source and decryption occurs at the destination Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Virtual Private Network (VPN)

(cont'd)

Security Audit

• Review of the state of the network • Auditing process: – Conduct a status quo analysis – Conduct a risk analysis – Make recommendations based on findings Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Other Security Threats

Internet Fraud

• Scams or other deceptive practices committed via the Internet, usually for the purpose of monetary gain or identity theft – Auction and retail scams – Business opportunity scams – Investment scams – Credit card scams – Purchase scams – Money transfer scams – Dating scams Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Identity Theft

• Fraud committed in your name by someone else who has illicitly gained access to your personal information • Methods used by identity thieves – Dumpster diving – Skimming – Phishing – Address changing – Stealing Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Lesson 6 Summary

          Identify various network attacks and ways to defeat them Describe authentication principles Explain the three major types of encryption Describe security zones Describe the function of a VPN Describe security audit principles Discuss mobile device management (MDM) Identify BYOD policies Identify security threats to cloud-based networks Identify ways to avoid anti-social activity (e.g., online stalking, cyberbullying) Copyright © 2012 Certification Partners, LLC -- All Rights Reserved

Network Technology Associate v2.0

 Introduction to Networking  Networking Components and Standards  Connecting to the Internet  Internet Services   Hardware and Device Connectivity Network and Cloud Security Risks Copyright © 2012 Certification Partners, LLC -- All Rights Reserved