Firewall Installation By Colton Podvorec

To Start Off A firewalls function is to screen a Networks Communication Preventing unauthorized access to or from a networked computer

What is a Firewall Maybe a single computer or a series of computers All communication passes through the firewall The firewall permits only traffic that is authorized by the administrator The firewall can withstand attacks upon itself

How it works Four categories Packet Filters Application layer gateways(proxy firewalls) Circuit level gateways Stateful packet inspection engines Packet filtering - Packets (small chunks of data) are analyzed against a set of filters. Packets that make it through the filters are sent to the requesting system and all others are discarded. l Proxy service - Information from the Internet is retrieved by the firewall and then sent to the requesting system and vice versa. Stateful inspection - A newer method that doesn't examine the contents of each packet but instead compares certain key parts of the packet to a database of trusted information. Information traveling from inside the firewall to the outside is monitored for specific defining characteristics, then incoming information is compared to these characteristics. If the comparison yields a reasonable match, the information is allowed through. Otherwise it is discarded

Microsoft ISA server 2000 enterprise Requirements .5 GHz processor 512 MB RAM 20 GB HHD 2 NIC

Start of Install Running a server with Microsoft server 2005/2008 Insert and run the CD Enter credentials Select ISA-firewall mode

Install Three options Choose Dedicated Template Dedicated template Limited Service Secure template Choose Dedicated Template Fully customizable Continue to fully install

Creating clients sets Creating client groups helps organize user groups such as department Select “create a client set” icon in results pane Name the group and use a description if the group is not a logical grouping like a department or lab name Enter machine addresses either individually or in IP ranges

Creating Client Sets Protocols Select the protocols which you intend to have rules on Such as HTTP, HTTPS, FTP And also select time frames for rules to be applied Default is full time unblocked access

Site and Content Rules Enables you to block specific IP addresses which may contain certain content Purpose of these rules is to specify different rules for web content, depending on a few factors Source IP address User Destination Content type

Setting Site & Content Rules Select Create a Site and Content Rule option from the Configure Site and Content Rules Option Create a name which easily identifies what the rule will do Next window is where you enter the site which is going to be blocked and check the deny option Optional to put a redirect site Ex. http://www.company.com/prohibited_site.htm This lists the blocked sites and the reasoning behind blocking them

Site & Content Rules cont. Next window then sets who you are blocking from this site, from the Client Group Sets which you established previously Ex. Accounting dept., or Computer lab A

This is a fast and easy way to start the firewall setup More complex rules should be created in order for the system to work up to its potential