Extranet Architecture
	Network Architecture Development Service

Extranet Architecture

Performance
Predictability, availability, and reliability are paramount in successful delivery of networked-library services. The increasingly central role network services play throughout the library community requires library consortia members to consider establishing a reliable and predictable network infrastructure to support current and next generation library services.

Cost Reduction
Of emerging importance is the role a network can play in lowering telecommunications costs by eliminating redundant dedicated connectivity to library service vendors. Obvia Corp. has seen instances where such initiatives have resulted in more than 50% network cost savings.

Need for a Network Architecture
The first step in establishing such a network is to create a network architecture that accommodates consortium members' current and future networking needs. The network architecture will serve as an architectural blueprint to support current and future library applications.
The architecture should be created to facilitate and coordinate future acquisition and deployment of network services. Architectural consistency is important to maximize acquisition and deployment of cost-effective and cost-efficient network resources and based upon an architecture flexible enough to enable rapid adjustment to unpredictable change. Strategic use of network services will enable consortium members to leverage scarce but essential network resources, to better maximize potential of library services.

Dependence on the Internet
The Internet has enabled many valuable new library applications. Its ubiquity and richness are unsurpassed. The Internet has given rise to the possibility of hundreds of libraries using the same contracts with online information service provider to realize lower costs. The modern library is highly dependent upon the Internet for its day-to-day operations.

Limitations of the Internet
Many library are now finding that traditional Internet based access to key online information providers is not adequate due to slow or unpredictable response time and availability. Some library have even threatened to stop investing in additional online resources until the problem can be fixed. Consortia may also be able to play a role in creating enhanced network access to these same information providers through an Extranet

Increased Dependence Ahead
An important evolutionary step in information resource sharing comes through shared access to common databases mounted consortially for hundreds of libraries to access. However, for guaranteed responsive access to such information, now potentially serving as a replacement for local print copy, the Internet is inadequate to support all libraries’ demanding needs of network performance and bandwidth capacity, especially during a peak usage period. Specifically, print copy replacement applications require a level of response time performance guarantee that the current Internet cannot deliver. Response time has a direct impact on not only how long it takes for a patron to complete his/her work, but also on how many patrons can be served.

Consortial Extranets-An Emerging Answer
To ensure adequate service performance, consortium members have to create one or more virtual private networks ("Consortial Extranets") to interconnect member libraries to library service providers. Members' library patrons connected to this network canl enjoy the benefits of reliable connection to the library service providers. Since these next generation library applications are Web-based, they appear transparently as Internet information resources to the library patrons.
By leveraging Internet technologies, consortium members can establish a network architecture that is standards-based, flexible and scalable. The Consortial Extranet will be one or more TCP/IP-based private networks. The Extranet can be built with cost-effective telecommunications services. To enable continuous growth, the Extranet architecture is designed to readily add new members as well as information database providers.

The Consortial Advantage
Library consortia have a long and sucessful history of sharing library services. To further this success, a collective effort to develop a Consortial Extranet lowers the initial costs of designing and implementing the network. Furthermore, the Consortium's collective purchasing power can be expected to lower or shift (to database resource providers) telecommunications costs.
In addition, the Consortial Extranet can lower telecommunications costs by sharing dedicated connectivity to one or more library service providers. Today, many individual libraries pay for dedicated connectivity or dial-up usage charges to access a number of library services. These expenses can be significantly lowered by all members of the consortium sharing predicable and reliable network connections.