EZProxy: Proxy by port or Proxy by Domain?

Is there a preferred configuration for use with BrowZine?
Third Iron strongly recommends using Proxy by Domain. After analyzing article access attempts at more than 300 institutions around the world over the last two years, we can say with great certainty that Proxy by Domain will give your users the BEST possible overall remote access experience, whether accessing your proxy server at home, coffee shops, an airport's shared wifi, or other access points.

Why does Proxy by Domain work the best?
Proxy by Port is the default configuration for EZProxy to make life easier for EZProxy administrators, but can make life unexpectedly more difficult for users. In Proxy by Port configuration, high port numbers are used, which may be blocked by the user's Internet Service Provider (ISP). 

Not only does your campus firewall configuration affect users, but so does the user's local ISP, sitting outside of your campus.  That ISP's firewall may prevent OUTGOING communication on that port. Users may be using many different ISPs if they access the server at home, at coffee shops, or another public wifi area.  

We have seen this problem numerous times, and this only affects proxy by port customers *or* those who have configured Proxy by Domain but are still running their server over a single, high-numbered port (such as 2048).

What does it look like when someone cannot access a link because of a blocked port?
Try visiting http://www.amazon.com:242.  Depending on your browser, it may either say it cannot be reached, or it may just "hang" without loading fully.  This is what it looks like when users try to use your library website setup as proxy by port remotely if their ISP is blocking their ports!  

In BrowZine, this manifests itself as a "loading..." screen that sits there and spins a long time, until the app "times out," and gives up trying to reach the journal article.  Because of the nature of port blocking, there is literally NO message returned back to the sender, unlike a "404 Not Found" error when a server simply tells a web browser that a page does not exist.  When a port is blocked, the receiving device literally hears nothing, even though by all indications their internet connection is working just fine.

Users are very mobile now, connecting from internet cafes, corporate networks, hospital waiting rooms, free wi-fi zones on trains, tethered to their cell phones and so on.  All of these services connect over port 80, but other ports are not guaranteed!  

In addition, the Internet Assigned Numbers Authority (IANA) publishes a list of common ports for official uses.  In the list linked above, you can see that while 2048 is listed, it is not specifically called out as "EZProxy".  Other common services in educational institutions like the EDUROAM network also publish a list of "minimum ports" for use by member institutions, and 2048 is not a recommended port to open.  

A researcher visiting Campus B from Campus A whose home campus (Campus A) uses Proxy by Port may not be able to connect to his home library remotely when connecting through the EDUROAM network!  However, if Campus A was Proxy by Domain, this would not be an issue, and the researcher would be able to successfully connect.

How do we switch over to Proxy by Domain?
You can find step-by-step instructions for switching your server to proxy by domain here:


It's very likely if you are set as proxy by port that your institution set up this proxy server a long time ago, and simply never migrated to proxy by domain when that became an available option.  In the early days of the internet before massive widespread adoption of wi-fi networks and cellular connections, port blocking and firewalls preventing access was much less of a problem.  Because trying to access a blocked port simply shows users a blank white screen in a web browser, and the user can do precisely nothing to fix it, most users simply give up or try again from another location thinking their "internet is just bad." Using Proxy by Domain will likely help your users from wherever they connect to your proxy server!

Questions?  Please contact Customer Support

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