SIEMENS EWSD Open Discrepancy Reports (TDRs) for Worldwide Certification

1. PROJECT MANAGER DEFENSE COMMUNICATIONS AND ARMY SWITCHED SYSTEMS COL David W. Ludwig IPTP Brief 13 July 2001

2. PURPOSE • •To discuss the SIEMENS Elektronisches Waehl System Digital (EWSD) open Discrepancy Reports (TDR’s) which affect Worldwide Certification Test

3. AGENDA • • BACKGROUND • • TDR DISCUSSIONS • • SUMMARY

4. BACKGROUND • •The EWSD switch has been performing successfully at S/W Release 16 in the European Network since August of 2000 with no significant user issues • •S/WRelease 18 was certified on 27 Apr 01 for use in the DISN-E • • Variety of Government requirements documents; CJCSI 6215.01/GSCR/SIC 94, 98/LSSGR/ANSI/Contract • •EWSD upgrades to S/W Release 18 in May and June 2001 are performing successfully • •The TDR’s have been identified as critical to obtaining Worldwide Certification • •Briefing will focus on these, but all of the TDR’s can be discussed in depth

5. TDR DISCUSSIONS TDR 18036 (Method 2 Route Selection for Preemption) -TDR DESCRIPTION • The EWSD does not currently provide Method 2 trunk route selection in accordance with GSCR Paragraph 5.3.7.1.2. - TDR DISCUSSION • Method 2 steers a call preemption to the primary route, before searching for idle trunks in alternate routes. • Method 2 trunk route selection does not appear to be used by the Army in CONUS or Europe. • Contractor is committed to providing Method 2 route selection in EWSD S/W Release 19. • Method 2 trunk route selection should not be critical for global certification.

6. TDR DISCUSSIONS TDR 18044 (Method 1 Route Selection for Preemption During an Alternate Route Connection Failure), TDR 18070 (Method 1 Route Selection for Preemption {All Precedence Levels} During a Direct Route Connection Failure), TDR 18072 (Handling of Precedence Calls During a Multiple Glare Hold Condition), and TDR 18073 (Handling of Precedence Calls During a Multiple Glare Release Condition). - TDR DESCRIPTION • The EWSD is unable to complete all calls regardless of their precedence as a result of an adjacent switch and/or a transmission failure. •Abnormal trunking situations (Wink and Glare irregularities)

7. TDR DISCUSSIONS - TDR DISCUSSION • CJCSI 6215.01 discusses Military unique requirements and Military unique features. - Assured services to “optimize call completion rates”. - Special C2 users (Flash/Flash override) will be provided with Non-Blocking service. - Multi Level Precedence Preemption (MLPP) by itself can not assure a totally Non- Blocking network (Block Precedence Announcements (BPA) and Transmissions Systems). - A total Non-Blocking network will not be cost effective in accordance with CJCSI 6215.01 Enclosure A, Paragraph 6F. -Under Exceptional procedure if the network cannot complete a precedence call request the calling party should receive a blocked precedence announcement (GSCR Paragraph 2.2.1.3). - The GSCR provides implementation instructions for Military features. • Preemption Techniques - JIEO 8249 (GSCR) Paragraph 5.3.7.1.2 states that calls failing to find an idle trunk in the direct route or any alternate route will enter a preemptive search for a trunk. - In the JITC test there were always idle trunks available; preemption was not appropriate.

8. TDR DISCUSSIONS - TDR DISCUSSION • Call Processing - Paragraphs 5.1.1 and 5.2.2 of the GSCR state how call processing should be done by the DSN switch. Both paragraphs point to the requirements of Section 5 of the LSSGR (commercial) unless specifically instructed differently. In the cases of these TDRs the GSCR does not instruct differently. - Section 5 of the LSSGR cross-references Section 6 of the LSSGR which addresses wink start and glare abnormalities in detail. - Under abnormal conditions the LSSGR requires the switch reselect another trunk. If the reselected trunk behaves abnormally, the call should be sent to reorder tone. - The EWSD has features that can monitor and manage trunk irregularities. - The EWSD behaves IAW the GSCR and the LSSGR (commercial standards).

9. TDR DISCUSSIONS TDR 18045 (Route Control Digit) - TDR DESCRIPTION • The EWSD does not implement the route control digit. - TDR DISCUSSION • There is no documented requirement in the GSCR for the route control digit. • The requirement in the System Interface Criteria (SIC)versions of 1994, 1998, and 2000 describe route control digit as “optional”. • The only locations where the route control digit may be used is in the MCI CONUS backbone switches. • There are no instructions for implementing the route control algorithm in the System Interface Criteria versions of 1994, 1998, and 2000. - If the EWSD were to implement route control digit requirements as stated in the System Interface Criteria versions of 1994, 1998, and 2000, the result would likely cause interoperability problems. • Route Control Digit is for MF 2/6 CAS signaling only (not SS7). • EWSD provides robust routing control (demonstrated at the JITC).

10. TDR DISCUSSIONS TDR 18055(Four Logical Circuits Per X.25 Physical Connection) - TDR DESCRIPTION • The EWSD does not provide 4 logical circuits over one physical interface for network management. - TDR DISCUSSION • The System Interface Criteria requires “4 distinct circuits”, not 4 logical circuits. • The EWSD provides 4 distinct circuits on three physical X.25 ports. • The Dual Data Port (DDP) and Enhanced Dual Data Port (EDDP) provide the means to transport these circuits to the Army and DISA simultaneously • The EWSD meets LSSGR requirements. • The DDP has been working successfully since August 2000. • PM DCASS supports the implementation of a direct network management interface between the Advanced DSN Information Management Support System (ADIMSS) and the EWSD. • PM DCASS is awaiting testing by the JITC of a direct network management interface between the ADIMSS and the EWSD. • Results of EDDP testing at the JITC provides a high confidence level that the EWSD will successfully provide the direct network management interface.

11. TDR DISCUSSIONS TDR 18058 (RSU Traffic Report Outgoing Peg Counts) - TDR DESCRIPTION • The Remote Switching Unit does not differentiate between incoming and outgoing peg counts. - TDR DISCUSSION • RSU is connected to the host EWSD, not directly to the DSN backbone. - All traffic management reports required are provided and total peg count is accurate. - Impact of RSU traffic is properly accounted foron the DSN backbone by the host switch. • There are other methods to manage the network; depending on traffic data is only one method. • Should not be critical for global certification. • Siemens has committed to fix this in a future S/W Release.

12. TDR DISCUSSIONS • TDR 18032 (Attendant Console Class of Service Display) • - TDR DESCRIPTION • The EWSD attendant console did not provide a class of service display as required by GSCR Paragraph 2.1.3.2. • -TDR DISCUSSION • Class of Service in the LSSGR is a collection of attributes (Precedence Level and Calling Area of individual subscribers?) • DISN-E Class of Service provided to attendant through SCCNMS Dial Service Assistance (DSA) console. • Class of Service database in DSA console is synchronized to Precedence Level and Calling Area settings for each subscriber in the associated switch database. • Not required for most Army CONUS switches and should not be critical for global certification. 

13. SUMMARY •The EWSD has been successfully operating within the DISN-E since August 2000 • There are inconsistencies among the government requirements documentation • Requirements documentation and implementation guidance point to commercial practices • The EWSD is a commercial switch competitively awarded under commercial acquisition procedures • These TDR’s should not prohibit Worldwide Certification • The operational risk presented by these TDRs is low and should not prohibit Worldwide Certification