Utilities in Computer systems

Utilities in Computer systems

1. In computers, a utility is a small program that provides an addition to the capabilities provided by the operating system. This is also optimized to perform at its best also it is configured so it makes it possible to run on the operating system that your computer system is running.

2. Firewall

   • A firewall is a system designed to prevent unauthorized access to or from a private network. Firewalls can be implemented in both hardware and software, or a combination of both.
   • Common firewall techniques
     • Firewalls are used to protect both home and corporate networks. A typical firewall program or hardware device filters all information coming through the Internet to your network or computer system. There are several types of firewall techniques that will prevent potentially harmful information from getting through
       • Proxy server
         • A proxy server intercepts all messages entering and leaving the network. The proxy server effectively hides the true network addresses.
       • Packet Filter
         • Looks at each packet entering or leaving the network and accepts or rejects it based on user-defined rules. Packet filtering is fairly effective and transparent to users, but it is difficult to configure. In addition, it is susceptible to IP spoofing.
       • Application Gateway
         • Applies security mechanisms to specific applications, such as FTP and Telnet servers. This is very effective, but can impose a performance degradation.
       • Circuit-level Gateway
         • Applies security mechanisms when a TCP or UDP connection is established. Once the connection has been made, packets can flow between the hosts without further checking.

3. Defragmenting