Networx Unit Pricer

Circuit Switched Data Service (CSDS) Technical Summary

CSDS is a mature switched data service provided by GSA in previous local and long distance telecommunications contracts. Some Agencies continue to use CSDS, particularly in the area of on-demand video conferencing applications.

CSDS provides a synchronous, full duplex, totally digital, circuit switched data connection at data rates from DS0 to DS1, including integral multiples of DS0 data rates (i.e., NxDS0, where N = 1 to 24) to on-net and off-net locations for compressed video conferencing and as a backup circuit for a dedicated circuit.

CSDS calls can be initiated from Government-specified terminals, such as digital PBX, Intelligent MUX, Group 4 FAX, Video codec, and Workstation/PC.

CSDS is interoperable with the Public Switched Telephone Network (PSTN) and all Networx CSDS contractors' networks. The figure below illustrates CSDS connectivity from on-net locations, such as Agencies served by Digital-PBXs and Centrex Central Offices.

Technical Capabilities

CSDS supports the full range of technical capabilities that are available in commercial offerings. These capabilities include:

• Calling capability will not require scheduling (i.e., available on-demand, without a reservation).
• Following call establishment, all bit sequences transmitted by the DTE are transported as data/bit transparent and maintain data/bit sequence integrity.
• For calls terminating to off-net locations, the bandwidth requested by the originating on-net location will be limited to the bandwidth limitations in the PSTN between the contractor's network and the called location.
• CSDS uses the same uniform numbering plan as for Voice Services (VS) and is integrated with the Voice Services (VS) plan.
• CSDS uses the same Authorization Codes as specified for Voice Service (VS).
• CSDS provides network-derived clocking to the Data Terminal Equipment (DTE) or PBX/Multiplexer (MUX) at the Service Delivery Point (SDP).
• CSDS supports the following dialable information-payload bandwidths:
  • DS0 (56 kbps and 64 Kbps) data rate.
  • DS1 (1.536 Mbps) data rate.
  • Multirate DS0 (NxDS0, where N= 1 to 24) data rates.
  • For the Multirate DS0 category, the contractor will provide the following:
    • Appropriate dialing sequence for initiating calls with different bandwidths.
    • Transport of all bit sequences transmitted by the DTE as data/bit transparent after establishment of the dialing sequence.

These and other service capabilities are detailed in Section C.2.2.2.1.4 Technical Capabilities of the Networx contracts.

Features

CSDS also offer features that complement the basic service. These features are described in Section C.2.2.2.2 Features of the Networx contracts:

• Dial-In - Toll-free numbers where available commercially.
• User-to-User Signaling Via Integrated Services Digital Network (ISDN) D-Channel*.

* The optional User-to-User Signaling Via ISDN D-Channel feature may not be provided by all Networx contractors.

CSDS is similar to the Circuit Switched Data Service offering on the FTS2001 contracts.

Each Networx contractor may provide variations or alternatives to the offering and pricing for CSDS. The specific details can be found within each contractor's Networx contract and pricing notes for CSDS.

For more information on the general CSDS specifications and requirements, please refer to Section C.2.2.2 of the Networx contract for technical specifications and Section B.2.2.2 for pricing.

CSDS Price Basics

CSDS provides a synchronous, full duplex, totally digital, circuit switched data connection to on-net and off-net locations for compressed video conferencing and as a backup circuit for a dedicated circuit. CSDS provides circuit switched service at data rates up to DS1, including integral multiples of DS0 data rates (i.e., NxDS0, where N = 1 to 24) to on-net and off-net locations. Calls can be either:

• CONUS to CONUS.
• CONUS to OCONUS/Non-Domestic.
• OCONUS/Non-Domestic to CONUS.
• OCONUS/Non-Domestic to OCONUS/Non-Domestic.

AT&T, MCI, and Sprint can integrate VS and CSDS traffic on the same dedicated access arrangement CLIN--a capability that was available on the FTS2001 contracts. Qwest also provides this capability but for only the CSDS CLINs with "Single PRI" in the CLIN descriptions (see CLINs 20150 - 20173). Integrating VS and CSDS traffic may reduce costs by reducing the number of required access arrangements. There is no contract requirement to integrate VS and CSDS traffic on the same dedicated access arrangement.

CSDS provides a similar capability to FTS2001 Circuit Switched Data Service.

Price components required for full end-to-end service for CSDS:

• For switched access origination:
  • CSDS Transport per-six second increment charge.
  • Access: Originating and terminating access costs are included in transport price.
• For dedicated access origination:
  • CSDS Transport per-six second increment charge.
  • Access: DAA Originating and Terminating Wireline Access (MRC) and (NRC).
• Features ordered as needed by the Agency:
  • Dial-In.
  • User-to-User Signaling Via ISDN D-Channel.
• Service Enabling Devices (SEDs) may be required to implement CSDS. [Please note that SEDs under Networx replace the FTS2001 User-to-Network Interfaces and Access Adaptation Functions (UNIs/AAFs). SEDs may differ between Networx providers. The pricing structure for SEDs provides for either a one-time payment or monthly term payments for purchase, plus a NRC for installation, and a MRC for maintenance.]

Each Networx contractor may provide variations or alternatives to the offering and pricing for CSDS. The specific details can be found within each contractor's Networx contract files and pricing notes for CSDS.

For more information on the general CSDS specifications and requirements, please refer to Section C.2.2.2 of the Networx contract for technical specifications and Section B.2.2.2 for pricing.