Firewall Wk. 4

Proxy servers are also known as proxy services or application proxies. They are dedicated firewall software applications which assesses the application layer information kept in the IP packet. It dedicated a device to an application. The proxy servers work as a software go-between, and screen data to choose if to block or accept traffic with regard to rules of the administrator. They however take time to assess, vary and recreate the packets and respond to requests.

Proxy Servers scan and act on data segments that are found on IP packet. They basically act in support of internal hosts through receiving, rebuilding and sending outbound applications. The Proxy Servers work as a software that sends data in the internal and external hosts (Holden, 2004). They also are keen on the port that every service applies for instance screening traffic that go in or out of the port and choosing whether to hinder or allow traffic with regard to rules. They finally increase the time to communicate which in turn hide the clients, change the network addresses and filter contents.

There are a number of steps that take place in a proxy transaction. The internal host sends a request to use a web site. The request heads to the proxy server which assesses the header and data of packet alongside the rule. The server then reproduces the packets with a new IP address. The server then transmits packet to its location. The packet returned is taken to the proxy server that assesses it again and compares it using the rule. The Proxy server recreates the packet returned and directs it to the original computer.

The Proxy Serves and Packet filters are applied together in firewall to offer several layers of security. They operate at the Application layer though inspect the varied segments of the IP packets and handle them variedly (Holden, 2004). The packet filters is connected to the internet. They are configured so that external traffic is permitted if it is intended for a service offered by the proxy server. It is located in the safeguarded side of the perimeter.

The Proxy servers contrast to the packet filters in a number of ways; through scanning the data of IP packets and provide additional log file listings. They also recreate packet with new source IP data. The server over the internet and internal host are not connected directly to each other. It is similarly more important to the network communications. Also attacks of the packet are made to not reach the internal host.

The main objective of these proxy servers is to hide internal clients, hide the URLs, block and filter data, safeguard e-mail proxy, advance performance, guarantee security, issue client verification and redirect URLs. The configuration for the Proxy Server is based on scalability matters; desire to do it on every piece of client software using it, desire to have contrasting proxy to the network protocol, the size of the server has to be in line with the size of traffic that goes through every gateway and desire to create packet filter rules and security issues as well as the upgrading of the machine having the server with increase of the users (Holden, 2004). The Proxy can create the filter rules which are; optimizing the performance of the proxy setting, making it possible for the hosts to bypass the proxy, filtering the URLs, making the internal handlers to direct outbound demands at some instance and control the time period for a session.

The proxy server has the ability to note the single point of failure. The network may be removed from the network completely. The networks have other ways of making the traffic to flow as well as balancing the load on the network. It is also bale to note the buffer overflow issues. Issues that arise from misconfiguration, noting the buffer overflow and noting the manufacturer’s web sites for patches.

The configuration of the Proxy serves takes into consideration a number of issues, for instance the consideration for size which if occupied may affect clients, has to be done properly; the proxy itself or every piece of the client software using the proxy server, the security matters.

When working with the client configuration, it is done so as to make it operate with the proxy server; there is the specification of the FTP and Gopher interfaces, and the browser has the ability to make use of the SOCKS standards (Holden, 2004). In the configuration of the file, the browsers found on the network can spontaneously acquire the proxy settings. The service configurations have a general purpose firewall which is composed of proxy server that monitors the inbound and outbound traffic.

When selecting a proxy server there is some that are commercial, others safeguard a service and serve Web pages kept in cache, while others are integrate to a greater firewall and some are standalone proxy servers. These proxy servers are of three types; transparent, nontransparent and SOCKS based.

Firewalls are found on the proxy servers for instance; Squid for a number of operating systems, WinGate which is used for windows these two are for small businesses, and Microsoft Internet Security and Acceleration Server substituted by Microsoft Forefront Management Gateway and the Sun Java System that is now Oracle iPlanet Proxy Server 4.0 that are applied in big business and there is Symantec Enterprise and T.REX. This is reliant on one’s platform and the size of host and services requiring safeguarding (Holden, 2004). The wrong choice of proxy server slows traffic, and impossible verification. If one does not want to use the Proxy Server one may interface to firewall using SSL encryption or ISP.

References

Holden, G. (2004). Guide to Firewalls and Network Security: with Intrusion detections and VPNs. Boston, Massachusetts: Inc. Thomson Learning.