Data Communications & Security Terms

Data Communications & Security Terms

Intruder
An Intruder is a person who attempts to gain unauthorized access to a system, to damage that system, or to disturb data on that system. In summary, this person attempts to violate Security by interfering with system Availability, data Integrity or data Confidentiality. 

Active Intruder and Passive Intruder
A passive intruder just listens and records the control and data messages on the channel and doesn’t make any modification to the message, while the active intruder can remove messages from the channel and/or add messages into the channel. An active intruder threat involves a situation where an individual or individuals access a system with the intention to cause serious harm.

Intruder Lockout
Some systems monitor failed Authentication attempts, and if too many attempts to sign on with a single account are detected, the Account is locked. This mechanism is intended to deter an Intruder, who may attempt to guess the password for one or more Accounts.

Audit Trail
An Audit Trail documents all security events. These include authentication attempts, change request input and authorization, access provisioning and deactivation events, Password Synchronization and reset, profile updates, etc.

Biometric Authentication
Biometric Authentication is any process that validates the identity of a user who wishes to sign into a system by measuring some intrinsic characteristic of that user. Biometric samples include finger prints, retinal scans, face recognition, voice prints and even typing patterns.

Breach of Confidentiality
A Breach of Confidentiality is a Security violation where the Confidentiality of some data was lost.
Cryptographic Certificate
A Cryptographic Certificate is a user's Public Key, which has been signed and encrypted using the private key of a well-known Certificate Authority. This allows the user to give out his or her Public Key to others, and allows those others to trust that it is, in fact, the user's correct Public Key. Ex. www.verisign.com

Encryption
Encryption is a process of translating a message, called the Plaintext, into an encoded message, called the Ciphertext. This is usually accomplished using a secret Encryption Key and a cryptographic Cipher. 

Two basic types of Encryption are commonly used:
Symmetric Encryption, where a single secret key is used for both encryption and decryption.
Asymmetric Encryption, where a pair of keys is used -- one for Encryption and the other for Decryption.

Decryption
Decryption is the reverse process to Encryption. Frequently, the same Cipher is used for both Encryption and Decryption. While Encryption creates a Ciphertext from a Plaintext, Decryption creates a Plaintext from a Ciphertext.

Encryption Key
An Encryption Key is a sequence of numbers used to encrypt or decrypt data.

Private Key
A Private Key is a secret key, used in Asymmetric Encryption. It is mathematically equivalent to a Public Key, but is kept secret. This is one half of a matching key-pair.

Public Key
A Public Key is a publicly distributed key, used in Asymmetric Encryption. It is mathematically equivalent to a Private Key, but is widely distributed. Public Key's are frequently certified by a Certificate Authority, so that users of this key can verify its authenticity. 

Public key encryption system
AKA as Asymmetric Encryption. It uses two keys where, one key encrypts, only the other can decrypt. The keys are interchangeable, in the sense that if key A encrypts a message, then B can decrypt it, and if key B encrypts a message, then key A can decrypt it. 
In public key encryption, one of the keys is known to both receiver and sender. The key is public in other word. The other key is known only by sender.

Hash
A Hash is a code, calculated based on the contents of a message. This code should have the property that it is extremely difficult to construct a message so that its Hash comes to a specific value. Hash's are useful because they can be attached to a message, and demonstrate that it has not been modified. If a message were to be modified, then its hash would have changed, and would no longer match the original hash value.

Denial of Service
A Security intrusion which causes a system to be damaged, and where the damage is sufficient to disable at least one of the services offered by that system, is called a Denial of Service.

Fault Tolerance
Sytem includes multiple, redundant servers, and continues to offer full functionality even when one of those servers ceases to function.
It detects failures in updates to target systems, and automatically retries failed operations until they succeed.

Loss of Integrity
A set of data is said to have suffered a Loss of Integrity if some event has caused it to be corrupted or incorrectly altered. This constitutes a Security violation.

Session Hijacking
Session Hijacking is any Security attack, carried out by an Intruder, which attempts to insert commands into an active Login Session. On wide-area TCP/IP networks, this is frequently attempted using IP Spoofing. On local TCP/IP networks, this might be attempted with the help of a Packet Sniffer. 

Firewall
A Firewall is a system which limits network access between two or more networks. Normally, a Firewall is deployed between a trusted, protected private network and an untrusted public network. For example, the trusted network might be a corporate network, and the public network might be the Internet. A Firewall might grant or revoke access based on user Authentication, source and destination network addresses, network protocol, time of day, network service 
or any combination of these. It might be implemented as an Application Level Firewall or a Packet Level Firewall. It might also implement a Content Filter, such as a Virus Wall.

Packet Level Firewall
A Packet Level Firewall protects an internal network against unauthorized access and attack from a public or external network by blocking some packets. Packets may be blocked based on source IP address, destination IP address, source or destination TCP port number, other packet header fields, time of day or user authentication. Filtering is carried out on a packet-by-packet basis, and the entire Packet Level Firewall may be implemented on a Router. Normally all filtering happens inside the Operating System, which makes this type of Firewall very fast.

IP
IP is the Internet Protocol. It is a mechanism by which packets may be routed between computers on a network-of-networks. IP allows computers to be connected using various physical media, ranging from modems to Ethernet cabling, fiber-optic cables and even satellite and radio links. IP is designed to be robust, and to gracefully handle the loss of some connections. Individual packets of data are routed by hosts with little knowledge of the overall network structure - just a few local routing rules. The global Internet is constructed using the IP network protocol.

IP Spoofing
IP Spoofing is a security exploit where an Intruder attempts to send packets to a system which appear to originate from a source other than the Intruder's own. If the target system already has an authenticated TCP session with another system on the same IP network, and it mistakenly accepts a spoofed IP packet, then it 
may be induced to execute commands in that packet, as though they came from the authenticated connection. Improved reliability and routing filters in major Internet routers make this attack largely obsolete on the Internet in cases where the Intruder and target system are topologically distant.

Packet Sniffer
A Packet Sniffer is a program that can record all network packets that travel past a given network interface, on a given computer, on a network. It can be used to troubleshoot network problems, as well as to extract sensitive information such as Credentials from unencrypted Login Session's.

HTTP
HTTP is the Hyper-Text Transfer Protocol. It is the most popular network protocol for exchanging documents on the World-Wide Web. Uses port 80.

FTP
Ftp is the file transfer protocol. It is based on the TCP/IP network protocols. Ftp allows a user on one machine to send files to or retrieve files from an Ftp server. FTP uses User ID / Password Credentials, sent as Plaintext over the network, with no Encryption, for Authentication. Uses port 21.

HTTPS
HTTPS is the Hyper-Text Transfer Protocol with SSL Encryption. It is the most popular network protocol for establishiing secure connections for exchanging documents on the World-Wide Web. It is basically HTTP carried over a TCP socket, which has been secured using SSL. (Uses port 443)

SSL
SSL is the Secure Socket Layer. It is a protocol that encrypts a single TCP session. Using this Asymmetric Encryption, all data exchanged over a TCP socket can be cryptographically protected. SSL is the base of HTTPS - the secure WWW protocol. 

TCP
TCP is the Transmission Control Protocol. It is used to establish connection-oriented, sequenced and error-free sessions over IP networks.

UDP
UDP is the User Datagram Protocol. It is used to send individual packets across an IP network, in an unreliable fashion. This means that successful, error-free delivery of a message is not guaranteed. 

SMTP
SMTP is the Simple Mail Transfer Protocol. It is the most popular protocol for transferring electronic mail on the Internet. SMTP is quite robust, but provides no facilities for Authentication of the sender or recipient; for encryption; or for attaching non-ASCII data. (Port 25)

SNMP
SNMP is the simple network management protocol. It is used by network management frameworks to manage and monitor network devices, such as hubs and routers. Some computer systems also respond to SNMP queries.  (Port 161)

Telnet
Telnet is a TCP/IP protocol that allows a User to remotely Login to a Unix, VMS or mainframe system, and execute commands in that Login Session. Telnet does not use Encryption. However, Ssh is functionally equivalent and secure. (Port 23)

POP3 
POP is an application-layer Internet standard protocol used by local e-mail clients to retrieve e-mail from a remote server over a TCP/IP connection. (Port 110)

SMTP
Simple Mail Transfer Protocol (SMTP)—used for e-mail routing between mail servers. The Internet standard for electronic mail (e-mail) transmission across Internet Protocol (IP) networks. (Port 25)

SSH
Ssh is the Secure Shell and improves on them by incorporating Asymmetric Encryption and a simple Public Key Infrastructure. 

IMAP
Internet Message Access Protocol (IMAP)—management of email messages. (Port 143)

Virtual Private Network
A Virtual Private Network is software hosted on two machines, which forwards network traffic between them. The packets exchanged between the machines is protected against Intruder's equipped with Packet Sniffer's using Encryption. All packets that pass through the network are encrypted, and so provide little or no 

value to an Intruder.A Virtual Private Network makes it possible to pass private data over a public network, thus simulating a private network without the expense of separate, protected communication media.

Proxy Server
A Proxy is a server that forwards requests from a community of users to the Internet, and retrieves those documents from the World-Wide Web. WWW Proxies are useful since they can cache documents (and avoid downloading them repeatedly), control access to documents (thus acting as a Content Filter) and scan for 
Viruses (thus acting as a Virus Wall). They also can be used to access wesites annonymously hiding your IP.

Spam
Spam is unsolicited electronic mail, usually delivered over the Internet. Some SMTP servers can filter out Spam (thus making a Spam Filter). Some jurisdictions are trying to make Spam illegal. 

Spam Filter
A Spam Filter is software that processes electronic mail messages, either for a single user or an entire network. While processing these messages, the Spam Filter attempts to identify Spam messages, and deletes them. 

WHOIS
Whis is a query and response protocol that is widely used for querying databases that store the registered users or assignees of an Internet resource, such as a domain name, an IP address block, or an autonomous system. Ex. whois kaputa.com gives information on kaputa.com

Domain Name System (DNS)
The Domain Name System (DNS) is a hierarchical distributed naming system used in internet. DNS translates domain names to IP addresses needed by users of internet.

Cisco CCENT Introduction

Cisco CCENT Introduction

Foundations: What is a Network?
Why do we need a network? 
What does the network accomplish for us? 

Foundations: OSI
The OSI Model and layers of network functionality.

TCP/IP: Addressing Fundamentals
TCP/IP concepts, IP address format, public and private addressing, and address classes. 
Why having TWO addresses is the key to successful network communication?

TCP and UDP 
When it communicates across the network using TCP or UDP? 
This decision determines how reliable the data transfer will be. 

Port Numbers
Port numbers help network communication between devices, allowing you to dictate what service you are trying to reach. 

Two Packets
Big picture perspective of packets on a local network communication and remote network communication using packets

Ethernet
Ethernet defines the standard for LAN communication around the world. 
Undersand how networks operates. Ethernet standard, CSMA/CD (the rules of communication), and the architecture of a MAC address.

LANs Physical Connections
crimping Ethernet cables, primary physical standards of Ethernet: UTP and Fiber Optics, straight-through vs. crossover cables, and an end-to-end picture of cabling in a corporate environment.

LAN Switches
Ethernet's use of CSMA/CD allowed it to obtain much faster speeds than its competitor (token ring); however, it also led to many problems with collisions in larger networks. Understanding of how the network switch fits into our network environments.

Working with the Cisco Switch IOS
How to work with IOS, Cisco's operating system: 
general navigation and help features of the IOS.

Setup of a Cisco Switch
IOS initial configuration of a Cisco switch. meaning of the physical LEDs on a switch, 
the initial boot process and configuration dialog, and the configuration of a VLAN interface.

Configuring Switch Security
Initial security of your switch, primarily focusing on configuring passwords, logon banners, and SSH.
Enabling port security for your network, control of the number and type of devices that attach to your network.

Optimizing and Troubleshooting Switches
common problems in a LAN environment.
improving your efficiency on Cisco devices.

Wireless Networking
foundations of wireless networks including radio frequency, wireless channels and standards, 
and the best way to design wireless for your organization.

Wireless Security and Implementation
Security vulnerabilities
steps to take to successfully implement and secure a wireless network.

Advanced TCP/IP
converting from decimal to binary and back
advanced TCP/IP addressing, IP subnetting
the ability to separate IP addresses into subnets based on the number of networks an organization needs
ability to separate IP addresses into subnets based on the number of hosts an organization needs in each network the ability to reverse engineer subnets based on the IP address and subnet mask that has been given

Routing: Initial Router Configuration
initial configuration of a Cisco router.

Routing: SDM and DHCP Server Configuration
graphic user interface (GUI) based Cisco Security Device Manager, or SDM
Cisco router management through the SDM.

Routing: SDM and DHCP Server Configuration
Dynamic Host Configuration Protocol (DHCP) 
configuring a DHCP server using SDM.

Routing: Implementing Static Routing
configuring the foundational form of routing known as static routing.

Routing: Implementing Dynamic Routing with RIP
dynamic routing works much better when you want to get the job done fast.
configuration of the RIP routing protocol  for small network environments

Routing: Internet Access with NAT and PAT
Network Address Translation (NAT) 
how to use the Cisco SDM to configure your router to support NAT Overload 

Routing: WAN Connectivity
types of WAN connections and configuration

Management and Security: Telnet, SSH, and CDP
management and security strategies for Cisco devices
configure and monitor our devices are Telnet and SSH. 
how to navigate through Cisco devices
Cisco Discovery Protocol (CDP) to unveil an undocumented network.

Management and Security: File Management
ability to copy files to and from your routers and switches 
to back up configurations and IOS versions
moving files to and from these file systems.

Understanding CSS Selectors

We have seen that CSS is a list of rules that tell our browser how to display the HTML, and we have looked at how rules are formed. Let’s look in more detail now at selectors.
In this lesson we learn about one of the main parts of a CSS rule: CSS selectors.

Use the buttons below to navigate through the lesson

Remember, a selector is the part of a CSS rule that goes outside of the curly braces “{” and “}”. This tells the browser which elements the rule acts upon.

For example a selector a applies to ALL <a> tags. The selector html applies to all <html> tags.

What about this selector that is in our example?

.important

Remember when we learned about classes and ids earlier in the course? If not, you should go and review the lesson “Class, ID and <div> and <span> in HTML” which came in the last part of the course.

Just in case, here’s a reminder. Class and id are both attributes we can put on our HTML tags. We put a class on any tags we want to share particular CSS rules, and we put an ID on any tags we want to be unique.

For example:

<h1 id=”mainHeading”> We only want ONE main heading, so we give this tag a unique name. We only have ONE element with any ID on a page.

<li class=”important”> We might want lots of elements to be marked as ‘important’ so we make a class called important and apply it to LOTS of elements.

To put a CSS selector via ID we use the “#” symbol, and for a class we use the “.” symbol.

So our rule .important applies to any element with a class of “important”.

If we wanted to apply a rule to only one element, then we give that element an ID, e.g. id=”myElement” and then create a rule for it:

#myElement { … }

What if we had a lot of elements that we had marked with a class, but we only wanted some of them to have a particular rule? For example, imagine this HTML:

<li class=”important”>Some list item</li>
<li>Another list item</li>
<a class=”important”>Here’s a link!</a>

We don’t want to change the way our ‘important’ things appear everywhere, but we do want our link to have something extra, maybe be in bold.

We can do this by combining parts of our selectors. We can specify BOTH a type of element and a class, like this:

a.important { font-weight:bold; }

This means that this rule only applies to elements <a> that have a class “important”.

Similarly, we could use an ID in the same way:

a#myUniqueLink { font-weight:bold; }

Of course, since there should only be ONE id #myUniqueLink on the page then we can have the same effect without the “a”.

Inherited Selectors

What about the very long selectors we have in our example CSS file? Look at this one:

nav ul li a { color: white; }

This specifies FOUR tags.

When we list tags like this, we are saying that we only want this rule to apply to tags that are inside the preceding tag. So we would translate our rule as saying “apply this rule to any <a> tag that is inside an <li> that is inside a <ul> that is inside a <nav>”.

So only links inside our <nav> get colored white!

This means we can have different rules for different parts of the page, like this:

#mainSection a { color: orange; }
#otherSection a { color: green; }

Now any <a> tags inside the tag with ID #mainSection will appear orange, while any <a> tags inside the tag with ID #otherSection will appear green!

Pseudo Selectors

Finally there are some selectors called ‘pseudo selectors’. These apply to elements that are in certain states. For example:

a:visited { color:purple; }
a:hover { color: orange; }

This kind of selector is mostly seen with the <a> tag. Remember, <a> is a link. Links can be visited or unvisited. Often websites show you a different colored link when you click it – that is achieved using the a:visited pseudoselector. Now when you click a link on our page, it shows as purple so you know you’ve already been to it.

Similarly, :hover allows you to change an element when your mouse hovers over it – so we get a nice visual effect on our links by changing their color when we hover them.

Selector Specificity

This is a complex topic, but it’s important to understand how different rules apply. Remember the golden rule is:

The most specific rule always wins

For example:

<p id=”someParagraph” class=”superSpecial”>What colour is this text?</p>
<style>

#someParagraph { color: red; }
.superSpecial { color: blue; }

</style>

What colour will our paragraph be?

It has BOTH a class and an ID. And one tells it to be red, and the other tells it to be blue.

Since the most specific rule always wins, and an ID is more specific than a class (because you can only have ONE ID) we know that the #someParagraph rule will “win” and it will be red.

Similarly, any rule that specifies a type of element is more specific than one that does not:

p.superSpecial { color: yellow; }
.superSpecial { color: green; }

In this case the colour will be yellow because the first rule is more specific: it only applies to <p> elements whereas the second rule applies to any element with the class .superSpecial.

It can be very difficult to understand specificity – the best way is to practice and experiment with your own website. We want to give you the ability to start experimenting for yourself so you can learn by experience!

Partitions and Volumes

Hard Disks perform a very simple function – to store data and then reliably retrieve it on command. However, before any information can be stored on a hard disk it must be both partitioned and formatted with a file system. A hard disk can contain multiple partitions and file-systems. As you will learn later this can be extremely useful.

A partition is a persistent division of a physical hard drive into logical segments. Each partition appears to the user like a separate hard drive. Volume is the terminology used by post-Windows 2000 machines for partition. Volumes are much more flexible in their configuration than the more rigid partitions.

Partitioning a hard drive makes each segment behave like a separate disk. This is ideal for dual-booting different operating systems.

Basic Partitions

Primary Partitions

• There may be up to 4 Primary Partitions per physical disk.
• The Boot partition may only be located on a primary partition.

Extended Partitions

• Extended Partitions can use up any free space not used by the Primary Partitions.
• You may have up to 3 Primary partitions and one extended partition on any physical disk.
• Extended Partitions need to be further divided into Logical DOS drives.

Logical-DOS Partitions

• Logical Partitions are placed inside the extended partition.
• The number of Logical partitions you may have is only limited by the number of free drive letters.
• The boot partition cannot be placed on a logical partition.

Basic Partitions

The oldest Windows operating system is always installed first as the newer operating system normally writes a new boot record.

A Logical Drive can contain an operating system but never the System partition.

Different Partitions may contain a File Systems not used by Windows, so if an additional operating system is required it can also be installed on the non Windows partition.

Creating a Primary Partition

To create a Primary Partition from within Windows 2003/XP, the Disk Management Utility is used. To access Disk Management, click on Start.

Right-click on My Computer.

Select Manage.

Computer Management will appear. Click on Disk Management.

Disk Management will appear. From this screen you may view, create and delete partitions.  To create a new Primary partition on Disk 1 right-click on the unallocated space on Disk 1.

From the choices menu, select New Partition.

The New Partition Wizard will appear. Select Next to continue.

The Partition Type page will appear. Select the type of partition required. Primary Partition is selected here. Click Next to continue.

Select a size for the new partition, in this case we will chose 2048MB.

Click on Next to Continue.

A drive may be made to appear as a folder on an existing drive (This is called Mounting). The Default Drive is the next available drive letter, in this case D. Select Next to continue.

You can also choose a Volume Label, which can be used to identify the volume. In order for the partition to be used by the operating system it will have to be formatted with a file system. NTFS is the file-system of choice for a Windows Server 2003 system. Click Next to accept the default values.

The summary page will appear. To close the wizard and create the partition click Finish.

The new Primary partition is now displayed on Disk 1 and has been assigned the drive letter D:.

The new partition also appears in My Computer.

Creating an Extended Partition

To create a new Extended Partition the Disk Management Utility is used. To create a new Extended Partition on Disk 1, right-click on the Unallocated space on Disk 1.

Select New Partition.

The New Partition Wizard will appear. Select Next to continue.

The Partition Type page will appear. Select Extended Partition.

…and then hit Next.

Specify the size of the partition. The maximum amount of space available on this disk is 2039 MB. To accept the default click Next.

The summary page will appear. To close the wizard and create the partition click Finish.

The new Extended Partition is displayed on Disk 1. In order to use the partition, logical drives will have to be created inside it.

N.B. The extended partition does not appear in My Computer as an extended partition without any formatted logical drives cannot hold any data.

Creating a Logical Drive

To create a new Logical Drive within the Extended Partition, right click on the Extended Partition on Disk 1.

Select New Logical Drive.

The New Partition Wizard will appear. Select Next to continue.

Logical Drive is selected, click Next to continue.

To specify the Logical Drive size click in the “Partition size in MB” box and change the value.

1024MB will create a 1GB Logical Drive . Click Next to continue.

A drive may be made to appear as a folder on an existing drive (This is called Mounting). The Default Drive is the next available drive letter, in this case E.

Select Next to continue.

NTFS has been selected for the file system. Select “Volume label” in order to give the new partition a recognizable name.

The new Logical Drive has been named WebSite, this describes the data the Logical Drive may contain. Click Next to continue

The summary page will appear. To close the wizard and create the Logical Drive , click Finish.

The new Logical Drive is now displayed inside the Extended Partition on Disk 1 and has been labeled WebSite (E:).

Similarly, the new Logical Drive appears in My Computer and is ready for use.

Dynamic Volumes

Because of the limitations of basic partitions, dynamic volumes where introduced in Windows 2000 and continue to be supported in Windows XP and Windows Server 2003.

Dynamic volumes offer more flexibility than standard partitions. One of the main reasons for using dynamic volumes is to make use of volume sets (which are covered later).

Unfortunately pre-Windows 2000 computers cannot read or utilise dynamic volumes, furthermore you should not use dynamic volumes in a dual-boot environment even if all the operating systems are capable of supporting dynamic disks.

Dynamic Volumes are only supported on Windows 2000/XP/2003.

There is no limit to the number of volumes you may have on a disk.

Dynamic Volumes may be fault tolerant.

There are no Primary, Logical or Extended volumes.



Power Management and UPS

A computer’s Basic Input/Output System (BIOS) is software through which the operating system communicates with hardware devices. Advanced Configuration and Power Interface (ACPI) is the current standard for the way the BIOS works. Windows supports not only ACPI but also some BIOS versions based on older Advanced Power Management (APM) designs. Some machines aren’t capable of supporting the ACPI standard, and in some the APM feature actually conflicts. Consult the HCL and be prepared to disable APM in the BIOS.

Power consumption of a computer’s  devices or an entire system can be reduced using Power Options. This is done by choosing a power scheme, a collection of settings that manages the computer’s power usage. A user can create his or her own power schemes ,or use the schemes provided with Windows. Power consumption of a computer’s  devices or an entire system can be reduced using Power Options. This is done by choosing a power scheme, a collection of settings that manages the computer’s power usage. A user can create his or her own power schemes ,or use the schemes provided with Windows. Power Options are available to any Windows XP machine, but they are especially important  to preserve battery life for laptop users.

Start > Control Panel > reveals this window.

If Power Options are available on the machine, this icon will be seen. Click on it……and the Power Options applet is revealed.  The tabs available may vary from machine to machine, but these are typically seen on a desktop machine.

This is the more complex display typically seen on a laptop computer.

The current settings are for a light use desktop computer. Note the power-hungry monitor will shut down if it’s idle for 20 minutes, but the hard drives remain live for a quick resumption of working.  In this configuration the monitor and the hard drive shut down to preserve battery power.  These settings can be altered to give a more ruthless power saving.  Save these changes to make a  new Power Option.

Once given a distinctive name, the option becomes available for future use.  The drop down window reveals the list of ready-made power options.

A basic ready-made option can be selected and used as it is, or settings for the monitor and hard drive can be modified for each option.

This tab presents an unimpressive set of choices. The option to have the indicator on the taskbar is a useful one, however.

Hibernation will allow you to save your computer’s current state before powering down. This will allow you to reboot the computer quickly, returning you to your previous session.

UPS Devices

These come in all shapes and sizes but essentially do the same job. In the event of a mains failure they provide emergency battery power to keep a system alive until it can be safely shut down, or until the power is restored.

A UPS device should do its basic job merely by being plugged in. However, it can only be configured by starting the UPS service.

First, the device has to be identified to the system.

Once a device has been selected options for configuration become available…Choose one, and click finish.

While the basic UPS function works as soon as the unit is plugged in, the configurable settings only work when the UPS Service is started. Unfortunately, no clue appears on screen as to whether the service is running or not. Delve into Administrative tools for this…

This list of services is accessed through Computer Management > Services.  The service needs to be started manually. (Right-clicking brings up the required menu.)

Hardware in Windows XP/2003

Hardware Support; Windows XP/2003 includes support for numerous devices, including DVD, multiple monitors, cameras and wireless communication.

Plug and Play (PnP); Plug and Play is a standard that allows hardware to configure itself, with the least amount of user-intervention.

Universal Serial Bus (USB); Allows you to connect devices to your computer without restarting.  USB1 runs at 1 to 12Mb/sec, USB2 at 480Mb/sec and both support Plug and Play.

Power Management; Supports APM (Advanced Power Management).  Supports ACPI (Advanced Configuration and Power Interface)

Interrupt Requests (IRQ)

Devices work by interrupting the processor. Once a device has the processor’s attention it can send or retrieve data or carry out a function.  The interruption of the processor’s run time is called an Interrupt Request (IRQ). Each device has an IRQ so the processor knows which device is asking for its time.

Interrupt Requests (IRQ) Conflicts

Here, both the Printer and the Network Card are using the same IRQ number. This has confused the processor, so it doesn’t know which device to service.

Input/Output (I/O) addresses

Sometimes devices CAN share IRQ numbers. Consider this case of two COM ports.  Every device on the computer has a unique address, called an I/O address. This address acts like a mailbox number that the processor uses to communicate with the device.  While here, both COM ports share an IRQ number but they have different I/O numbers. All I/O numbers must be unique and cannot be shared.

Direct Memory Access

Using DMA, a device can directly transfer data to the RAM without using the processor, thus freeing up the processor for other tasks.  . If two devices tried to use the same DMA channel, this would cause a hardware conflict.

Multiple Displays

Multiple Display Support. Windows XP/2003 adds support for up to nine display adapters.  Any video adapters used for multiple displays must either be PCI or AGP cards.  All video adapters must support multiple displays including any on-board cards.

On-board Video Adapters. If the the on-board video card is to be used as well as a separate video adapter, then install Windows XP/2003 before installing the new device.  Windows setup will disable any on-board video card if a separate video-adapter is located.  In some systems the BIOS will disable the on-board card if another adapter is found, there may be no way to overcome this.

Configuration. One video adapter must be set as the primary. This adapter cannot be switched off as the other adapters will use it as a marking point when extending the desktop.

Device Manager

Hardware is administered through the Device Manager utility, which is the user’s main administrative interface with a machine’s hardware.

It can be used to:

• Check the configuration of hardware devices
• Install or update drivers
• Remove or disable hardware

This utility can be accessed from Start > Settings > Control Panel >  System > Hardware tab > Device Manager.

Alternatively, right-click on My Computer > Properties > Hardware tab > Device Manager.

A device can be uninstalled from this window. When the device is selected, the window changes subtly.

Note this icon. Hardware changes can be detected in the device by clicking this.

This feature is available from the Action menu or from right-clicking on an item. If the item is expanded, more operations are available:

Note these icons. Hardware devices can be disabled or deleted from here.  Alternatively, right-click on the highlighted device, or click on the Action button.  You must be logged on as an administrator or a member of the Administrators group in order to complete this procedure. Domain wide policies must also permit this!

An Exclamation Mark indicates a device has a problem. Generally this will be a driver issue.

A red cross indicates that the device has been disabled.

To check the properties of a hardware item, double click on the icon, or right click and select Properties.

The message that a device is working properly does not always means it’s doing what is required of it.  Devices can be enabled or disabled as required dependent upon the hardware profile required.

The number and type of tabs varies according to the particular Hardware Device selected.  The Driver tab allows you to configure drivers for the device. A driver is a software interface that allows the operating system to use the hardware.

Common to all devices is the Resources Tab. This lists the computer resources used by the particular device to interact with the processor  and the computer memory.  Any conflict reported here implies that changes have to be made to the IRQ or I/O resources allocated to this device.