Link Rot in your Family Tree?-
A Case Study in the Dynamics of Internet Genealogy

The simple ability to update a family's history as ongoing research reveals new information is an extremely powerful tool. It gives every family historian the ability to publish the fruits of their research and, more importantly, to keep that information current. The use of the web as a publishing tool has freed us from the static confines of the printed word.

This power to revise and change a web site has attracted many family historians to the Internet as web site publishers - to the great benefit of us all. Never before have we had so much of other's research available at our fingertips. In the avalanche of personal web sites which provide genealogical information on the Internet, some interesting questions arise: Is the fluidity of web publishing a bad thing? Does the impermanence of web pages create a problem for genealogical research purposes?

The ability to modify a genealogy web site's contents is not the only issue involved in web site changes. Let's say that information displayed on your web site is of interest to a visitor regarding a suspected common ancestor. The visitor notes the URL of your web site in their research notebook as a possible lead and goes on their way. Some days or months later, the visitor wishes to revisit your web site to confirm the suspected lead and types in your URL. They enter in your URL and receive the message "URL Not Found" in reply. Where did your web site go? Did you move it? Did you change your site's file structure so that the old URL is now invalid? Did you stop paying your Internet Service Provider (ISP) bill and they removed your web site? Where did your web site go? When a web site changes URLs, the broken links to that web site's old URL on other pages are referred to as "link rot". Obviously, link rot or web site relocation can be as hazardous to Internet-based genealogy research as changes in web site content.

Pretty Pictures

There were a total of twelve web sites mentioned in the original article. Each had been selected for their successful use of graphics only - they were in no other way related to one another. All were authored by different individuals with different objectives for their sites. Several were hosted outside the U.S. Among the examples chosen were a USGenWeb state site, a USGenWeb county site from a different state, a genealogy society's web site, three country or area-specific general genealogy sites, and a state-wide online genealogy project site. The remainder of the sites were the personal genealogy pages of individuals. These sites represent a fairly diverse sample in regards to their purposes and objectives. Some provided links to other sites, some provided research information for particular areas, and some provided lineage information on specific families.

In February 1998, a New Zealander's e-mail directed the author's attention to the fact that many of the links to the twelve sites were broken. In other words, the URLs given in the original article no longer worked for one reason or another. Either the old links returned an error message stating that the URL could not be found or a web page was displayed with did not fit the article's description of that site.

All twelve links had been in working order when first published 16 months before. Obviously, the dynamic nature of the web had taken its toll on the currency of the links in the original article. The article clearly had a case of link rot. After thanking the observant New Zealander, the author began to investigate which links were broken and why they no longer worked. This case study developed out of that investigation.

What Changed?

Title:	South Carolina GenWeb
Original URL:	http://www.geocities.com/BourbonStreet/1783/
Problem:	URL changed due to change in state co-ordinator. ISP re-assigned original URL to another individual.
New URL:	http://www.geocities.com/Heartland/Hills/3837/
Title:	Johnson Family Tree Home Page
Original URL:	http://ourworld.compuserve.com/homepages/johnson_gen/
Problem:	URL Not Found.
New URL:	-
Title:	Dutch Genealogy Links
Original URL:	http://wwwedu.cs.utwente.nl/~hoitink/links.html
Problem:	URL Not Found. Academic ISP changed domain name for hosting user web sites.
New URL:	http://www.twente.nl/home/genealogy/links.html
Title:	Viki's Little Corner of the Web
Original URL:	http://www.novia.net/~vikia/
Problem:	None. No change to URL or graphics.
New URL:	Unchanged.
Title:	History & Family Tree of John Jewell
Original URL:	http://www.dcscomp.com.au/bruce/family/
Problem:	URL changed. Left forwarding page at old URL.
New URL:	http://www.dcscomp.com.au/jewell/family-history/
Title:	Wayne County, Illinois GenWeb
Original URL:	http://bl-12.rootsweb.com/~ilwayne/
Problem:	Graphics changed.
New URL:	Unchanged.
Title:	Swedish Genealogy Page
Original URL:	http://www.ts.umu.se/~petersj/swegen.html
Problem:	None. No change to URL or graphics.
New URL:	Unchanged.
Title:	Kentucky Biographies Project
Original URL:	http://www.starbase21.com/kybiog/
Problem:	None. No change to URL or graphics.
New URL:	Unchanged.
Title:	Czechoslovak Genealogical Society International
Original URL:	http://members.aol.com/cgsintl/index.html
Problem:	URL Not Found.
New URL:	- (see Author's Note below)
Title:	Genealogy Corner
Original URL:	http://www.geocities.com/Heartland/1657/genealogy.html
Problem:	URL Not Found.
New URL:	-
Title:	Bill & Peggy's Genealogy (formerly Bill Holder's Home Page)
Original URL:	http://www.rapidramp.com/bhold/index.html
Problem:	DNS Entry Not Found. ISP is no longer in business or no longer uses the same domain name.
New URL:	http://home1.gte.net/wh7262/index.htm
Title:	Palatine & Pennsylvania Dutch Genealogy Page
Original URL:	http://www.geocities.com/Heartland/3955/index.html
Problem:	Graphics changed.
New URL:	Unchanged.

To summarize the condition of the original 12 links after sixteen months, 7 links were broken, 3 links had not changed either URLs or graphics, and 2 links had not changed URLs but had changed graphics. Of the 7 links which were no longer functional, replacement URLs for 3 sites could not be found. These 3 links then were truly "dead". For the other 4 broken links, new URLs for the same site could be found by one means or another.

It is interesting to note that for the genealogy web sites in the sample, the most prevalent form of change was a change in URLs. Changes to web site content in the form of changes to graphics was the least common form of change. Since the web sites in this sample were originally selected for their graphics, a change in graphics makes a good proxy for measuring changes in other content.

The Mechanics Behind the Changes

The change in URL for Dutch Genealogy Links was for a different reason entirely. The site is hosted by the University of Twente in the Netherlands. The University changed the domain name under which their users' accounts are maintained. User accounts are now hosted under www.twente.nl rather than under wwwedu.cs.utwente.nl. So while the academic ISP which hosts the site remained the same, an internal re-organization of the University's domain names caused the original URL to go dead.

Re-organization is also the cause of the change in URLs for the History & Family Tree of John Jewell site. In this case, however, the change is not a result of a domain name change. The ISP hosting this site in Australia did not change domain names nor did the author move his site to another ISP. In fact, the directory structure on the ISP's server which hosts the History & Family Tree of John Jewell changed. The directory structure changed from /bruce/family/ to /jewell/family-history/ , thus changing the part of the site's URL to the right of the (unchanged) domain name. Since the author of this site is Bruce Jewell, it appears that the ISP may have changed their account holders' directory structure from a first name to a last name basis. This is most likely the result of growth in the ISP's business.

The History & Family Tree of John Jewell site is noteworthy for how the author of the site handled the change in his URL. When visiting the old URL, the following message appears:

This "change of address" message resides at the old URL. No visitor should be confused by this clearly written message which includes a clickable link to the new URL where History & Family Tree of John Jewell now resides. How thoughtful of Bruce Jewell to put this message in place of his old URL! This helpful "we've moved" message should be standard practice for any web site author who changes their directory structure or moves ISPs. Bill & Peggy's Genealogy was formerly titled Bill Holder's Home Page but the title change does not relate to why its URL changed. This fun web site's URL changed because its author has changed ISPs - not once but twice. The error message returned by entering the old URL is "DNS (Domain Name Service) Not Found". This means that the Internet no longer recognizes the domain name given in the URL. Either the old ISP has gone out of business or they chose to no longer maintain their old domain name. Bill & Peggy's Genealogy was "found" again on the Internet using Cyndi's List of Genealogy Sites on the Internet. Bill Holder had updated his new URL information on Cyndi's List so that visitors can still find his web site. However, since changing URLs the first time, Bill has changed ISPs yet again. So at his first new URL - http://cust2.iamerica.net/wh7262/ - there is a "we've moved" message:

Once again, the web site author has thoughtfully provided a clickable link to the new URL. This time, even the reason for the second move is given in the message.

The Reasons for Change