Sits between two networks used to protect one from the other places a bottleneck between the networks
Download
1 / 20

Sits between two networks Used to protect one from the other Places a bottleneck between the networks - PowerPoint PPT Presentation


  • 96 Views
  • Uploaded on
  • Presentation posted in: General

Sits between two networks Used to protect one from the other Places a bottleneck between the networks All communications must pass through the bottleneck – this gives us a single point of control. Compare network and transport protocols to a database of rules and

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha

Download Presentation

Sits between two networks Used to protect one from the other Places a bottleneck between the networks

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


  • Sits between two networks

    • Used to protect one from the

      other

    • Places a bottleneck between the

      networks

      • All communications must pass through the bottleneck

        – this gives us a single point of control


  • Compare network and transport

    protocols to a database of rules and

    then forward only the packets that meet

    the criteria of the rules.

  • Implemented in routers and sometimes

    in the TCP/IP stacks of workstation machines

    • in a router a filter prevents suspicious

      packets from reaching your network

    • in a TCP/IP stack it prevents that specific

      machine from responding to suspicious traffic

      • should only be used in addition to a

        filtered router not instead of a filtered router


  • Since an enterprise owns the computing and network facilities used by employees, it is perfectly within it’s rights to attempt to limit internet access to sites that could be somehow related to business

    • Since the proxy server is a natural bottle neck for observing all of the external requests being made from the internal network it is the natural place to check content

    • This is usually done by subscription to a vendor that specializes in categorizing websites into content types based on observation

    • Usually an agent is installed into the proxy server that compares URL requests to a database of URLs to reject

    • All access are then logged and reported, most companies then review the reported access violations and usually a committee reviews and decides whether or not any personnel action should be taken (letter of reprimand, dismissal, etc)

    • Sites that are usually filtered are those containing information about or pertaining to:

      • Gambling

      • Social Networking sites.


  • Used to connect two private

    networks via the internet

    • Provides an encrypted tunnel

      between the two private networks

    • Usually cheaper than a private

      leased line but should be studied on

      an individual basis

    • Once established and as long as the encryption

      remains secure the VPN is impervious to exploitation

    • For large organizations using VPNs to connect

      geographically diverse sites, always attempt to use

      the same ISP to get best performance.


  • Blocks packets based on:

    • Source IP Address or range of addresses.

    • Source IP Port

    • Destination IP Address or range of addresses.

    • Destination IP Port

    • Some allow higher layers up the OSI model.

  • Common ports

    80HTTP

    443HTTPS

    20 & 21FTP

    23Telnet

    22SSH

    25SMTP


  • http://www.bu.edu/

  • http://www.comodo.com/resources

  • http://www.howstuffworks.com

  • http://www.wikipedia.org/

  • http://technet.microsoft.com


ad
  • Login