What is a proxy and why are they useful?
A proxy is simply a middle man for internet requests. When you request a webpage without a proxy you contact the webserver and ask for that page and it sends it back to you, the server then knows your IP address which is like a physical address that can be used to track your access on that website.
When you use a proxy to request a webpage you send your webpage request to the proxy and then it is the one to request the webpage, the webserver will then return the webpage to th eproxy which then sends it back to you. This way the website doesn't ever see your IP address and cannot attribute the webpage request to you.
Proxies essentially hide your identity from the websites you visit, this is especially helpful when trying to harvest lots of targets from search engines.
What is the difference between public and private proxies?
Private proxies are proxies that are bought / rented from a proxy provider and generally will come with few to no limitations on their use. In the majority of cases private proxies will be completely anonymous and will not send your IP when posting.
Public proxies are often scraped from publically viewable websites or downloaded from websites, they are nearly always being used and abused by many different users and are not guaranteed to provide any amount of uptime. Often a public proxy will not stay live for more than a few minutes to a couple of hours as well as be slow and may not even keep you anonymous while posting which completely negates the reason for using proxies in the first place.
I would never advise anyone ever use public proxies of any kind for posting with NHSEO as you will see lower than expected results but for searching they are a must.
When are proxies needed?
Proxies should be entered for searching, these can be public proxies but if you are using public proxies for searching ensure that the list is checked and updated regularly to ensure your proxies are working correctly.
Proxies are also needed when limiting by PR as Google only allows a certain number of PR requests from a given IP within a short time.
When used with custom comments will likely improve your approval rate
If you are experienced in blog commenting you can increase your approval rate by using your own custom comments coupled with good private proxies for posting. Using private proxies may help to avoid filters such as akismet and the custom comments may help your comments to appear more natural and user submitted rather than auto submitted. If your comments look more natural they are more likely to be accepted.
UPDATE:
How to use the new proxy controls
As the use of proxies is now advised for searching there have been some new controls added that allow the use of third party proxy searching tools such as Proxy Goblin, Proxy Multiple and QProx.
To use these tools follow these instructions:
1) Ensure that you output your proxies to a file that is always accessible by No Hands SEO, the implementation of this will vary depending on your application but should be very simple, ensure that the file name and location stays consistent.
2) Go into NHSEO proxy settings tab and click on the corresponding Browse button
3) Select the file that contains your proxy list
4) Check the option for "Continually Update Proxies From File?"
5) Click the Save Button
I will start to research some proxy providers when I get chance but for the time being if you have any suggestions on proxy providers to look at I would appreciate a heads up on who you would or wouldn't advise and why.