A proxy server acts as an intermediary between a client device and the internet. It allows clients on a local network indirect access to outside networks like the internet. There are different types of proxy servers that provide advantages like improved security and performance through caching but also have disadvantages like potential slower speeds. Popular proxy server software includes Microsoft ISA Server, Squid, and WinRoute, while common hardware proxies include Cisco PIX and Blue Coat.

1. Proxy Servers PROXYMITY- CC8 Team members Chaithra T R 1MS08IS402 Tejus .R 1MS07IS107 Vijetha P.C 1MS07IS114 Vishal Agarwal 1MS07IS116

2. Contents: What is proxy ? Main purpose of using proxies How a proxy works ? Proxy types Advantages/Disadvantages Popular hardware & software proxies References Acknowledgements

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 Proxy share a connection to others LAN INTERNET

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

5. Advantages: 1. Security. 2. To speed up access to a resource –”caching”. 3. To censor network services or content. 4. Improve performance. 5. When you connect to a website, your true IP address will not be shown, but the proxy servers IP will, this does not mean that your completely anonymous. The proxy server will have logs of IP’s that used the proxy server. Then why need of proxy??? To avoid access to particular webpages. To hide your IP address,hence no room for hackers.

6. Disadvantages: Proxy services lag behind nonproxied services. Proxy services may require different servers for each service. Proxy services usually require modifications to clients, procedures, or both.

7. Improve Performance 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. INTERNET 64 Kbps 128 Kbps 512 Kbps 1 Mbps

8. Proxy types Web proxies Transparent proxies Open proxies Anonymous proxies Proxy setting in IE

9. How does a proxy server work? A proxy server receives a request for an Internet service. If it finds the page, it returns it to the user without needing to forward the request to the Internet. If the page is not in the cache, the proxy server, acting as a client on behalf of the user, uses one of its own IP addresses to request the page from the server out on the Internet

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

11. IP : 172.16.0.2 Gw : 172.16.0.1 IP : 172.16.0.1 IP : 217.219.66.2 Gw : 217.219.66.1 LAN INTERNET Proxy Server Source IP 172.16.0.2 www.yahoo.com Dest IP 209.191.93.52

12. 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 Change Source IP Address LAN INTERNET Proxy Server Source IP 217.219.66.2 www.yahoo.com Dest IP 209.191.93.52 Source IP 172.16.0.2 www.yahoo.com Dest IP 209.191.93.52

13. IP : 217.219.66.2 Gw : 217.219.66.1 IP : 172.16.0.1 Change Dest. IP Address IP : 172.16.0.2 Gw : 172.16.0.1 LAN INTERNET Proxy Server Source IP 209.191.93.52 Dest IP 217.219.66.2 Source IP 209.191.93.52 Dest IP 172.16.0.2

14. IP : 217.219.66.2 Gw : 217.219.66.1 IP : 172.16.0.1 Change Source IP Address & Destination IP Address IP : 172.16.0.2 Gw : 172.16.0.1 LAN INTERNET Proxy Server Source IP 209.191.93.52 Dest IP 217.219.66.2

15. 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 LAN INTERNET Proxy Server Source IP 209.191.93.52 Dest IP 172.16.0.2

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

17. Thank You, References : www.cisco.com www.isaserver.org www.wikipedia.com www.cert.org www.isc.sans.org www.zonelabs.com www.symantec.com www.mshdiau.ac.ir

18. Regards to Mr Siddesh Mr Rajaram Gowda Acknowledgements