IPv4 and IPv6

You might have heard of World IPv6 Day, held on June 8, 2011. Major organizations, such as Google, Facebook, Yahoo!, and universities like Indiana University have participated. Like many others, you might have wondered how and why this was important to the average internet user. This post will explain the issue: IP (Internet Protocol) address exhaustion. The IP address here refers to IPv4 (IP version 4), which was introduced in 1980 and is the current Internet Protocol. Because the number of available IPv4 addresses is diminishing, IPv6 (IP version 6) will eventually become the standard protocol in the near future.

The IP address exhaustion is derived from the IPv4 addressing structure. An IPv4 address is made up of four 8-bit (totaling 32 bits) sections, and is expressed as four numbers between 0 and 255 separated by a period like this: This “Dot Decimal Notation (DDN)” is a human readable form, but actually computers communicate in binary form, 0s and 1s, so the address above in decimal form will be like this in binary:

Decimal 129. 79. 38. 88
Binary 10000001. 01001111. 00100110. 01011000

• In the binary form, zeros are added between the bytes for a visual purpose.

This addressing structure gives a total IPv4 address space of 232, or 4,294,967,296. Although the pools of IPv4 look big, IPv4 address exhaustion has been expected because of the dramatic growth of the Internet. On February 3, 2011, the Internet Assigned Numbers Authority (lANA), which is responsible for global IP addressing, allocated the last five address blocks to the five Regional Internet Registry organizations which are responsible for IP addressing within a particular region. The Asia Pacific Network Information Centre (APNIC) was the first to exhaust its regional pool on April, 15, 2011.

IPv6, known as IPng (IP next generation), is the next IP address designed to replace IPv4 and is expressed as 8 groups of two byte hexadecimal values separated by colons. A typical IPv6 address looks like this: 1111:2222:3333:4444:5555:6666:7777:8888. This colon-hexadecimal structure increases the IP address space from 232 of IPv4 to 2128, approximately 340 undecillion or 3.4 x 1038 IP numbers, therefore, provides a much greater number of addressable nodes than IPv4.

These days, most computers have either an IPv4 address or both an IPv4 and IPv6 address as shown in the screenshot above. Until IPv6 completely replaces with IPv4, both IPv4 and IPv6 will exist side-by-side for the near future. The primary limitation to deploying an all IPv6 network is that, not all devices support IPv6 and many special purposes devices, such as network printers, still only support IPv4. In addition, many applications do not support IPv6 addresses yet and will not function correctly on an IPv6 only network.

For more about IU specific IPv6 environment, check at the Knowledge Base and IU Webmaster websites.

More about Blacklight, the new interface for IUCAT

Since the last post about Blacklight, we’ve been asked a lot of questions about Blacklight and its development in IU Libraries. Those of you who missed reading it might want to check here. This post will focus on some of the questions that we have been asked most frequently.

What sorts of changes will there be in the new IUCAT?

People involved in the development phase are working hard to insure that a new discovery interface not only retains the functionality of IUCAT currently available, but also delivers improved functionality.

Most next generation type catalogs have a simplified search box, which is easy and quick to use for users with a simple question. Blacklight provides a simple format for the basic search and facet structure for limiting searches.

The generic Blacklight interface is customized according to the library’s individual needs and specific environments. Here are some examples that adopt Blacklight’s basic format.

  • University of Wisconsin – Madison

  • Stanford University

  • University of Virginia

  • Johns Hopkins University

The new IUCAT will have a single search box for the basic search, and faceted searching on the left side will allow users to constrain searches by controlled vocabulary items. There will also be an advanced search screen for more focused searches.  As the development is still in progress, your comments and ideas will be highly appreciated.

How do Apache Solr and Ruby on Rails work to index library resources?

Blacklight’s two fundamental technologies are the Solr search server and the Ruby on Rails web application framework. Developed by the Apache Lucene project, Apache Solr is used for indexing and searching records, while Ruby on Rails is used to create the front end. Here is a nice graphic representation of the Blacklight system.

Sadler, B. (2009). “Blacklight Infrastructure.” In Project Blacklight: a next generation library catalog at a first generation  university. Library Hi Tech, 27(1), 57 – 67.

A java-based program SolrMARC reads, indexes, and exports library’s MARC records to Solr and custom Ruby scripts are used for non-MARC items to map document metadata to Solr. The Ruby on Rails application looks to the Solr server for its data, passes search queries, and formats search results.

If you are interested in what others are doing in Blacklight, you can ask a question on the Blacklight mailing list and see its codebase at GitHub.

A new interface for IUCAT: Blacklight

As you may have heard, work has begun on a new interface for IUCAT. The IU Libraries OLE Discovery Layer Implementation Task Force (DLITF) will be overseeing the implementation of a new discovery layer, powered by Blacklight, to overlay our current SirsiDynix system. Development work is going on during this fall semester and a public Beta will be launched in spring 2012. This is a good time to share some background information around the new discovery interface, Blacklight.

What is Blacklight?

Blacklight is a free and open source OPAC (Online Public Access Catalog) solution developed at the University of Virginia (UVA) Library; check the project site for detailed information. While some OSS (Open Source Software) systems, such as Evergreen and Koha, were developed to replace a library’s entire ILS (Integrated Library System), Blacklight has been designed to work with a library’s current ILS to assist in reengineering the library’s searching tools.  It uses Apache Solr for indexing and searching records and Ruby on Rails for its front end.

What are some of the features?

Blacklight features faceted browsing, relevance based searching, bookmarkable items, permanent URLs for every item, and user tagging of items. As it is capable of searching both catalog records and digital repository objects, digitized images or repositories become more discoverable for users.  Unlike MARC records, which use similar templates for different types of objects, the use of Ruby on Rails allows librarians to define behaviors that are specific to certain kind of objects.

Where can we see examples?

The Task Force will begin soliciting feedback on the local beta implementation in the near future, but in the meantime, if you would like to see more, there are other mature installations of blacklight you may review. The University of Virginia, Stanford University, Johns Hopkins University, and WGBH are the principal contributors to the code base. There are dozens of sites worldwide and here are some of heavy users:

If you have questions about the task force or the project, feel free to contact us!

Additional reading:

Sadler, B. (2009). Project Blacklight: a next generation library catalog at a first generation  university. Library Hi Tech, 27(1), 57 – 67. Access the full text.

Sadler, B., Gilbert, J., & Mitchell, M. (2009). Library catalog mashup: using Blacklight to expose collections. In Engard, N. C. (Ed.) Library mashups : exploring new ways to deliver library data. Medford, N.J. : Information Today, Inc. Access the record in WorldCat.org.