1. Proxy Servers & Firewalls

2. What is proxy ? What is proxy ? Main purpose of using proxies Main purpose of using proxies How a proxy works ? How a proxy works ? Proxy types Proxy types Popular hardware & software proxies Popular hardware & software proxies What is firewall ? What is firewall ? Main purpose of using firewalls Main purpose of using firewalls How a firewall works ? How a firewall works ? Firewall types Firewall types Popular hardware & software firewalls Popular hardware & software firewalls Objectives

3. What is proxy ? Proxy Proxy is hardware / software Indirect access to other networks e.g INTERNET. all computers on the local network have to go through it before accessing information on the Internet. Organization, universities, companies use proxy systems Proxy act as gateway Proxy act as Cache Server/Firewall Proxy share a connection to others LAN INTERNET

4. Main purpose of using proxies Improve Performance –A–A–A–Act as Cache server –B–B–B–Bandwidth control Filter Requests –P–P–P–Prevent access to some web sites!!! –P–P–P–Prevent access to some protocols –T–T–T–Time division Surfing Anonymously –B–B–B–Browsing the WWW without any identification!!!

5. Improve Performance Caching Caching –Reduce latency –Reduce Network Traffic Caching can greatly speed up Internet access. If one or more Internet sites are frequently requested, they are kept in the proxy's cache, so that when a user requests them, they are delivered directly from the proxy's cache instead of from the original Internet site. Caches diminish the need for network bandwidth, typically by 35% or more, by reducing the traffic from browsers to content servers. Bandwidth control Bandwidth control –Policy-based Bandwidth Limits –Deny by content type INTERNET 64 Kbps 128 Kbps 512 Kbps 1 Mbps

6. Filter Requests Prevent access to some web sites!!! –C–C–C–Categories web sites AAAAdult/Sexually Explicit AAAAdvertisements & Pop-Ups CCCChat GGGGambling GGGGames HHHHacking PPPPeer-to-Peer …………… –C–C–C–Check by content type ....Exe /.Com ....Mid /.MP3 /.Wav ....Avi /.Mpeg /.Rm

7. What do you need for proxy installation? Proxy Software Proxy Software  Ms ISA Server, Squid, WinRoute, … Server Server At least 2 network cards At least 2 network cards DIRECT INTERNET connection (Public IP Address) DIRECT INTERNET connection (Public IP Address) Switch/Hub (elective) Switch/Hub (elective) Private IP Address Private IP Address  10.0.0.1/8 – 172.16.0.1/16 – 192.168.0.1/24

8. How a proxy works ? See the next Demo See the next Demo

9. LANINTERNET Proxy Server IP : 172.16.0.2 Gw : 172.16.0.1 IP : 172.16.0.1 Source IP 172.16.0.2 www.yahoo.com Dest IP 209.191.93.52 IP : 217.219.66.2 Gw : 217.219.66.1

10. LANINTERNET Proxy Server IP : 172.16.0.2 Gw : 172.16.0.1 IP : 217.219.66.2 Gw : 217.219.66.1 IP : 172.16.0.1 Source IP 217.219.66.2 www.yahoo.com Dest IP 209.191.93.52 Change Source IP Address Source IP 172.16.0.2 www.yahoo.com Dest IP 209.191.93.52

11. LANINTERNET Proxy Server IP : 217.219.66.2 Gw : 217.219.66.1 IP : 172.16.0.1 Source IP 209.191.93.52 Dest IP 217.219.66.2 Change Source IP Address & Destination IP Address IP : 172.16.0.2 Gw : 172.16.0.1

12. LANINTERNET Proxy Server IP : 217.219.66.2 Gw : 217.219.66.1 IP : 172.16.0.1 Source IP 209.191.93.52 Dest IP 217.219.66.2 Change Dest. IP Address Source IP 209.191.93.52 Dest IP 172.16.0.2 IP : 172.16.0.2 Gw : 172.16.0.1

13. LANINTERNET Proxy Server IP : 172.16.0.2 Gw : 172.16.0.1 IP : 217.219.66.2 Gw : 217.219.66.1 IP : 172.16.0.1 Source IP 209.191.93.52 Dest IP 172.16.0.2

14. Proxy types Web proxies Web proxies SSL proxies SSL proxies Transparent proxies Transparent proxies Open proxies Open proxies Anonymous proxies Anonymous proxies Proxy setting in IE

15. Popular hardware & software proxies Software ProxyHardware Proxy Ms. ISA Server Cisco PIX Squid Blue Coat Kerio WinRoute Cyberoam 1st Up Net Server Alacer CCProxy CProxy Windows ICS WinGate

16. What is firewall ? Firewall Firewall is hardware / software protects the resources of a private network from users from other networks Organization, universities, companies use firewall systems Firewall can act as gateway Firewall can act as proxy Firewall filter Incoming & Outgoing information LAN INTERNET

17. Main purpose of using firewalls Packet filtering Packet filtering –Analyzing packets Proxy service Proxy service –Provide access to other networks e.g INTERNET LAN INTERNET 

18. How a firewall works ? The FIREWALL can now: Log the attempt Alert the admin Harden the firewall Or reset a TCP/IP connection Sniffing Mode 1) An attacker tries to compromise a service on the protected network. 2) The Firewall identifies the attempt. LOG Alert Reset Harden 

19. What firewall protects us from Remote login Application backdoors Operating system bugs Denial of service E-mail bombs Viruses SPAMs Trojans ICMP bombing FTP brute force Phishing ….

20. Popular hardware & software firewalls Software FirewallHardware Firewall Ms. ISA Server Cisco PIX Norton Internet Security Blue Coat Mcafee Internet Security Cyberoam ZoneAlarm Check Point KerioNetScreen BlackICE D-link SECURESPOT OutpostWatchGuard

36. Thank You, References : www.cisco.com www.cisco.com www.isaserver.org www.isaserver.org www.wikipedia.com www.wikipedia.com www.cert.org www.cert.org www.isc.sans.org www.isc.sans.org www.zonelabs.com www.zonelabs.com www.symantec.com www.symantec.com www.mshdiau.ac.ir www.mshdiau.ac.ir Communication & Information Technology Department of Mashhad University - IRAN Communication & Information Technology Department of Mashhad University - IRAN

37. Contact me : Poustchi@yahoo.com http://poustchi.blogspot.com