14.5 Networks - Preserving Network Security

A large part of a network administrators job is making sure the areas on the network are secure from unauthorised users.

The trouble is, where there is a computer system, there is a cracker ready to try and beat your security.

Methods to try and secure systems include:
- Physical controls (locks, steel doors, removable hard drives, armed guards etc.)
- Procedural controls (password rules, network usage policies, access times)
- Software controls (firewalls, virus protection, data encryption, access levels, auditing/monitoring)

There are lots of ways crackers can try to gain access to a network, here are some of them:

• Password guessing (can be checked for strength against compromising. Click here)
• Brute force attacks
• Packet sniffers
• Virus/trojan horses/Phishing/Garbaging
• Physical access
• Corrupting staff/legitimate users
  

But there will always be a loop hole ready to be exploited. The trick is, making sure you know when you have been cracked!

After putting together a set of operational procedures, checks on staff, latest software patches and up-to-date virus/firewall software, all the network administrator can do is monitor the network for strange behaviour which might indicate an attack - this can be automatically using network auditing software.

14.4 Communication and info systems - Overview

The Internet was first conceived by H.G.Wells in his work the Modern Utopia back in the early part of the 1900's. Wells foretold a time when anyone could access any information allowing society to be perfectly informed leading to the most rational society.

About 50 years later the American research agency ARPA (Advanced Research Project Agency) decided to create a network spanning America which would eventually enable the control of the US nuclear missile silo's. This remained it's primary function until it began to be used by academia.

In 1990 an Englishman called Dr Tim Berners-Lee created a simple programming language called HTML (Hyper Text Markup Language) which enabled everyone to be able to add pages of information to this ever-growing international network.

As more networks are interconnected around the world (internet growth), potentially 6billion minds are able to share their information. Is the H.G. Wells prophecy coming true?

In this unit we will look at the increasingly important role that networks and other communication systems play in modern life.

14.1 Backup strategy considerations

14.1 Backup strategies - Overview

14.1 Upgrades

14.1 IT mangers' responsabilities

14.1 Strategic implications of software, hardware and configuration choices

The responsabilities of an IT manager are:

• To promote high productivity of staff
• To ensure compatibility and ease of communication between departments and clients
• To ensure ease of support and maintenance
• To ensure all decisions are good value for money

So these responsabilities effect every decision that is made concerning the IT environment.


When developing an Information Management Strategy, an IT manager must make decisions on software, hardware and configuration choices.

Each choice has costs and benefits which must be considered alongside the immediate, and long term requirements of the organisation/company.

When considering SOFTWARE choices for the organisation:

"Off-the-shelf"

• Known functionality
• Proven technology
• Known costs

"Bespoke"

• Exactly what is required therefore can improve staff productivity
• Future proofing can be built in providing potential value for money

Standardise on interface:

• Ease of support
• Ease of compatibility between users

When considering choices for HARDWARE:

Type of workstations

• Identical workstations = easy maintenance and support
• A complete roll-out = too expensive so rolls out in stages throughout the year

Upgrading considerations:

• Software - improvements in functionality and ease of use
• Hardware - more speed, less likely to get spares
• Ethos - looks good to clients if the company has new PC's
• Task driven - maybe your sales force needs internet access on the road = laptop

Should you upgrade to the latest version?

Yes!

• Extra features for your users means they will work more efficiently

No!

• Time and cost of re-training
• Until training, users may not be able to use the new functions and be less productive
• More hardware resources needed
• May not have all previous functionality
• Potentially imcompatible file types
• Staged roll-outs may make different departments incompatible
• More complicated support needed for different versions

Should emulation (a piece of software or hardware that allows a computer to pretend to be another type) be considered?:

Yes!

• Can run legacy software - short term incompatibility upgrade fix
• Enables different departments running different h/w and s/w to communicate
• More software can be run on a h/w platform

No!

• Extra program running = more resources needed (or runs slower)
• Will not exploit new features of the hardware
• May not exploit full features of software being run

14.1 Policy and strategy issues

Senior IT Directors must create a central Information Management Strategy which considers:

• What data needs to be stored?
• How long should this data be stored?
• Where should this data be stored?
• How should this data be backed up?
• Data security.
• What data is needed to be collected/sent to other systems? (EDI, suppliers, clients etc.)
• Internal communication (chain of command, bulletins, shared workspace, mailing lists)
• Legal issues (DPA etc.)
• eg. School!

Why?

• Without careful planning, systems can grow in an unstructured way, leading to inefficiency, redundancy and incompatibility.

An Information Management Policy must ensure:

• ICT systems deliver the service cost effectively and without failure or delays
• ICT systems match business objectives and strategies
• ICT promotes competitive advantage by deploying innovative technology

Unit 5 - Policy, strategy and systems: Overview

• 14.1 Policy and strategy issues
• 14.2 Software - Evaluation of software
• 14.3 Database management concepts
• 14.4 Communication and information systems
• 14.5 Networks
• 14.6 Human/Computer interaction
• 14.7 Human/Computer Interface
• 14.8 Software development
• 14.9 Software reliability
• 14.10 Portability of data