A content delivery network is a system of computers containing copies of data placed at various points in a network so as to maximize bandwidth for access to the data from clients throughout the network. The Networx contractor provides CDNS which efficiently and rapidly delivers an Agency's content to Web browsers worldwide by reducing the infrastructure required to provide a domestic or global Web presence. CDNS providers guarantee that Agency content and applications will be available to constituents at all times, even in the event of periods of unexpected high usage, network outages, security incidents, and large-scale natural disasters.
The CDNS provider will incorporate equipment and algorithms to cache content on geographically dispersed servers on the Internet. When a request is made from a particular location for specific content, the server that can most rapidly and efficiently provide the content is dynamically identified.
CDNS consists of a collection of surrogate servers that attempt to offload work from origin servers (where content originates) by delivering content on their behalf. The servers belonging to a CDNS may be located at the same site as the origin server, or at different locations around the network, with some or all of the origin server's content cached or replicated amongst the CDNS servers. For each request, the CDNS attempts to locate a CDNS server close to the client Agency to serve the request, where the notion of "close" could include geographical, topological, or latency considerations.
The picture below shows a typical CDNS server site connected to the Internet.
Typical CDNS Server Site
CDNS addresses the following technical and operational issues:
CDNS is an application-layer service and therefore requires a connectionless data service, such as the Networx Internet Protocol Service (IPS), for the data transfer from the origin server to the CDNS servers.
CDNS supports the full range of technical capabilities that are available in commercial offerings. It is similar to Content Delivery Network Service on the FTS2001 contracts. These capabilities include:
CDNS will provide a continuous monitoring to ensure performance and quality of service. Measurements will include:
The contractor will provide statistics via a performance dashboard - a secure, Web-based portal accessible by Agency clients on a 24x7 basis. The performance dashboard will be consistent with commercial best practices.
These and other service capabilities are detailed in Section C.2.4.6.1.4 Technical Capabilities of the Networx contracts.
CDNS also offers features that complement the basic service. These features are described in Section C.2.4.6.2 Features of the Networx contracts.
Each Networx contractor may provide variations or alternatives to the offering and pricing for CDNS. The specific details can be found within each contractor's Networx contract and pricing notes for CDNS.
For more information on the general CDNS specifications and requirements, please refer to Section C.2.4.6 of the Networx contract for technical specifications and Section B.2.4.6 for pricing.
CDNS efficiently and rapidly delivers Agency's content to Web browsers worldwide. CDNS basic service consists of two main service types:
CDNS is ordered by specifying a monthly bandwidth commitment level and storage commitment level.
The CDNS NRC CLINs apply only to the initial service order. Therefore, when only upgrading or changing committed bandwidth levels, the NRC does not apply. Charges for underlying transport services from the origin server to CDNS servers are in addition to the CDNS charges. CDNS is similar to Content Delivery Network Service on the FTS2001 contracts.
Price components required for Domestic and Global CDNS:
Example 1: Domestic CDNS
Example 2: Global CDNS
Each Networx contractor may provide variations or alternatives to the offering and pricing for CDNS. The specific details can be found within each contractor's Networx contract files and pricing notes for CDNS.
For more information on the general CDNS specifications and requirements, please refer to Section C.2.4.6 of the Networx contract for technical specifications and Section B.2.4.6 for pricing.