Question

Q.4.1 Describe the differences between EBCDIC, ASCII, and Unicode? (9) Q.4.2 When designing or updating computer network systems, describe three factors you should consider for media selection criteria. (6)

Answer 1

Q:4.1

The American Standard Code for Information Interchange and the Extended Binary Coded Decimal Interchange Code are two character encoding schemes; which are more commonly known by their respective acronyms, ASCII and EBCDIC. The main difference between the two is the number of bits that they use to represent each character.The EBCDIC, ASCII, and Unicode encoding systems each use a different sort order for numbers, upper case alpha characters, lower case alpha characters, and special characters. As a result, if you load a partitioned table based on these characters, rows can be assigned to different partitions in the target table than they were in the original ASCII or EBCDIC source table, which might lead to unbalanced partitions in your database. You must determine if the partitioning keys need to be reevaluated when you migrate to Unicode.

The main difference between ASCII and EBCDIC is that the ASCII uses seven bits to represent a character while the EBCDIC uses eight bits to represent a character.IBM’s hold of the EBCDIC coding has led to many problems when it comes to updates. ASCII and EBCDIC later had updates to increase the number of characters that they can accommodate. ASCII pages had some code points replaced while maintaining most of the other code points. With EBCDIC, the different versions are highly incompatible with each other.

Differences:

ASCII	EBCDIC & UNICOCE
A character encoding standard for electronic communication	An eight-bit character encoding used mainly on IBM mainframe and IBM midrange computer operating systems
Stands for American Standard Code for Information Interchange	Stands for Extended Binary Coded Decimal Interchange Code
Uses 7 bits to represent a character	Uses 8 bits to represent a character
Represents 128 characters	Represents 256 character
Arranges the characters in consecutive order	Represents 256 character
Arranges the characters in consecutive order	Not compatible with modern encodings such as Unicode
More efficient	Less efficient

Q:4.2

Connectivity and Security:

Network connectivity today means more than Ethernet cables and wireless access points. People today are more connected while mobile than ever before and many of them want access to company email and data while they are out of the office. Balancing those needs while maintaining security is a challenge that needs to be addressed in the design phase of any network.This includes where data is stored, either in-house or offsite with cloud-based solutions, what types of information should be accessible, who should be able to access it, and which types of devices should be included. Firewalls and access servers need to be secure without slowing down operations.

Training, security, and scalability:

Training your staff on newly established policies is important and another aspect that determines how successful an IT network venture is. This goes double for security policies. Speaking of, security is not something to overlook. Properly assessing the strengths and weaknesses of your IT network will determine its stability in the future. It’s important to stress test the IT infrastructure and security against various threats. Otherwise, all the investment involved in creating the network will be threatened by malicious third parties. Scalability is also a crucial element. IT resources need maintenance, upgrades, and updates. Understanding expected network growth will help prevent surprise costs. It will also prepare your organization for necessary expansion, if/when the situation occurs.

Redundancy and Backing Up:

Redundancy means having backup devices in place for any mission-critical components in the network. Even small organizations should consider using two servers. Two identical servers, for example, can be configured with fail-safes so that one will take over if the other fails or requires maintenance. A good rule of thumb is to have redundant components and services in place for any part of a network that cannot be down for more than an hour.If an organization hosts it own Web servers, or cannot be without Internet connectivity, a second connection should be in place. Having an extra switch, wireless router, and a spare laptop onsite is a good practice for ensuring that downtime is kept to a minimum

Disaster Recovery Plan:

A detailed disaster recovery plan should be a part of any network design. This includes, but is not limited to, provisions for back-up power and what procedures should be followed if the network or server crashes. It should also include when data is backed up, how it is backed up and where copies of the data are stored. A comprehensive disaster recovery plan includes office disasters, building disasters, and metropolitan-wide disasters.In most cases, important data should be backed up daily. Many organizations do a full weekly backup, with daily incremental backups that copy any files that have been modified since the last weekly backup. Backup files should be stored in a secure location off-site in the event of a building disaster, such as a fire.