1. Install, configure and test ICT Networks
Unit 408
Install, configure and test ICT Networks

2. Outcome 2 Identify components that make up a network
Today's session
Summary of last week
Start Outcome 2
Practical

3. Last week Two types of Network Peer to peer Client Server
In a peer-to-peer network there are no dedicated servers or hierarchy among the computers.
All of the computers on the network handle security and administration for themselves.
Client Server
The network includes a File server and network Operating system

4. Last week A Server ? Server Hardware Basics
A server is simply a computer that is running software that enables it to serve specific requests from other computers, called "clients.“
Server Hardware Basics
Hot-swappable drives (drives that can be replaced while the computer is running) to speed adding or replacing hard disks
The ability to support multiple processors

6. Last week A server will include some applications Mail
Web (Internet Information services IIS)
SQL Database
Security (Internet Security and Acceleration ISA)

7. Last week What about the Clients how do they access the network
Clients are authenticated onto the network via the network server and its NOS.

8. Last week
The firewall ?
A firewall's basic task is to regulate the flow of traffic between computer networks of different trust levels
Typical examples are the Internet which is a zone with no trust and an internal network which is a zone of higher trust.

9. Last week VPN Secure ID token
A virtual private network (VPN) is a communications network tunnelled through another network, and dedicated for a specific network.
Secure ID token
Pre-authenticating users before they gain access to any servers

11. Last week Basic types Internet Connections ADSL?
Asymmetric Digital Subscriber Line
Upload speed is lower than download speed
SDSL?
Symmetric Digital Subscriber
Has same download speed and up load speed

12. Outcome 2 Identify components that make up a network

13. This week Fault tolerance Power Failure Data loss & Backups
Raid Arrays

14. Fault Tolerance & Recovery Procedure
A setup or configurations that helps prevent a computer or network device from failing in the event of an unexpected problem or error.
To make a computer or network device more fault tolerant requires that the user or company think of how a computer or network device may fail and take the necessary steps to help prevent the computer or network device from failing

15. Fault Tolerance ? Key areas Power Failure Power Surge Data Loss
Device Failure
Unauthorised access
Over Load
Virus

16. Fault Tolerance ? Power Failure
UPS to properly turn off the computer after a few minutes if the power is not restored to help prevent the computer from data corruption (Power surge also)
Redundant power supplies and cooling fans to allow the system to continue to function when a power supply fails or a fan stops working.

18. Fault Tolerance ? Redundant Array of Inexpensive Disks Data Loss?
Run a backup strategy
Grandfather-Father-Son Backup
Redundant Array of Inexpensive Disks
Mirror The server

19. Backup
Making a copy of an important file or files and putting them onto a floppy disk or another computer is the simple way of backing up your data although it is not the Ideal way especially for large files (greater that 1.44mb)
One way of backing up data is to install a second data drive and use the backup tool that comes with some versions of windows (98 upwards) and backup the data onto this second drive.
This is not the ideal (your computer may be stolen from your premises along with the backup).

20. Backup
A good way is to use a cd-writer in order to backup your files onto a separate removable CD allowing you to take the data Home or place it in a Fire safe.
With a DVD writer you can obtain about 10GB of data storage costing around £12 per disk.

21. Backup
For £200 a better way to backup data is to install a tape drive and backup your data to a tape this will allow 24GB of data to be backed up.

22. Grandfather-Father-Son Backup

23. Raid RAID 0 Striped set (minimum 2 disks).
Provides improved performance and additional storage but no fault tolerance.
Any disk failure destroys the array, which becomes more likely with more disks in the array.
A single disk failure destroys the entire array because when data is written to a RAID 0 drive, the data is broken into fragments.
The number of fragments is dictated by the number of disks in the drive.

25. Raid 5 RAID 5 Striped set (minimum 3 disks)
Requires all but one drive to be present to operate
Drive failure requires replacement, but the array is not destroyed by a single drive failure.
Upon drive failure, any subsequent reads can be calculated (Parity error checking)
The array will have data loss in the event of a second drive failure and is vulnerable until the data that was on the failed drive is rebuilt onto a replacement drive

27. Fault Tolerance ? Device Failure
It is often best to have a spare device ready to install
Some companies have duplicate servers on other sites that can be brought on line in the event of an outage or failure.
Sometimes there can be a dual power supply to the building in case of electrical issues
Some companies have their oven generators.

28. Install, configure and test ICT Networks
Unit 408
Install, configure and test ICT Networks