1、Quality Excellence for Suppliers of Telecommunications Forum (QuEST Forum) TL 9000 Quality Management System Measurements Handbook FR Examples Field Return (FR) Examples FR Examples 7-1 7 FR Examples 7.1 Basic Calculations Example 7.1-1 Each month the reporting organization reports the FRU return me
2、asures for the month based on all returns received during the month and the field population of units at the end of the prior month. The returns and population numbers are split into three separate groups depending on the age of the units. As an example, suppose during January 2010 there were a tota
3、l of 355 returns received out of a total population of 186,914 units. Of the 355 returns, 153 were shipped during the month or the prior six months. In other words, 153 of the units were shipped on or after July 1, 2009. Likewise, 163 of the returns were 7 to 18 months old having originally been shi
4、pped between July 1, 2008 and June 30, 2009. This leaves 39 units returned out of the long-term population, which are units shipped prior to July 1, 2008. Similarly the total population numbers are split into the three age groups. For purposes of this example, let us set these at 57,288, 99,626, and
5、 30,000 units respectively for the ERI, YRR, and LTR subsets of the population. In tabular form the data for the month is: The resulting calculations for the month are Early Returns from units shipped Jul-09 through Jan-10 Return = 100 x 12 x Index Total shipments for Jul-09 through Dec-09 = 100 x 1
6、2 x FRri/FRsi = 100 x 12 x 153/57288 = 3.20% One-Year Returns of units shipped Jul-08 through Jun-09 Return = 100 x 12 x Rate Total Shipments for Jul-08 through Jun-09 = 100 x 12 x FRry/FRsy = 100 x 12 x 163/99626 = 1.96% ERI YRR LTR Total Returns 153 163 39 355 Population 57,288 99,626 30,000 186,9
7、14 Field Return (FR) Examples FR Examples 7-2 Long-Term Returns from shipments prior to Jul-08 Return = 100 x 12 x Rate Total Shipments prior to Jul-08 = 100 x 12 x FRrt/FRst = 100 x 12 x 39/30000 = 1.56% More detailed examples using these same numbers are shown in 7.2 and 7.3 below. 7.2 Examples Wi
8、thout Normalization 1) Early Return Index, One-Year Return Rate and Long-Term Return Rate In a given reporting month, all returns are divided into three groups according to when they were shipped. For example, for the reporting month of January 2010, returns are divided into the following groups as
9、illustrated in Figure 7.2-1. Early Returns from units shipped in the period from July 1, 2009, through January 31, 2010. One-Year Returns from units shipped in the period from July 1, 2008 through June 30, 2009. Long-Term Returns from units shipped prior to July 1, 2008. 2009 2010 JAN FEB MAR APR MA
10、Y JUN JUL AUG SEP OCT NOV DEC JAN One-Year Returns Early Returns 2007 2008 DEC JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC Long-Term Returns One-Year Returns Figure 7.2-1 Shipping Date Groups for Computing Return Rates Field Return (FR) Examples FR Examples 7-3 Table 7.2-2 Example Returns Return
11、s from Shipment Population by Month Received Shipment Month Number Shipped Jan 2010 Feb 2010 Mar 2010 Apr 2010 May 2010 Jun 2010 Jul 2010 Aug 2010 Sep 2010 Oct 2010 Nov 2010 Dec 2010 Jun-08 & before 30000 39 44 42 46 31 35 48 36 46 41 32 30 Jul-08 8253 22 9 11 12 11 10 7 10 8 15 16 5 Aug-08 9243 11
12、11 14 12 19 15 13 1 16 10 13 21 Sep-08 9261 17 16 17 12 16 16 17 7 16 11 12 17 Oct-08 9721 19 13 21 15 17 11 14 19 16 18 17 13 Nov-08 10131 16 8 15 14 21 28 17 17 19 13 14 20 Dec-08 10140 24 16 17 22 12 19 17 15 24 14 15 14 Jan-09 6263 11 11 7 9 9 9 9 13 6 3 6 3 Feb-09 6436 7 9 8 11 10 8 5 5 3 14 7
13、9 Mar-09 7244 14 15 12 8 10 15 4 12 7 9 5 12 Apr-09 7275 10 9 14 10 9 8 10 6 12 11 11 10 May-09 7396 6 11 12 11 16 9 13 16 8 13 10 3 Jun-09 8263 6 13 12 16 11 7 9 12 14 13 7 13 Jul-09 8833 14 12 14 12 12 14 14 15 11 10 11 8 Aug-09 8954 16 6 14 17 14 14 11 14 12 12 8 13 Sep-09 9368 20 18 15 18 16 6 1
14、2 19 12 6 16 11 Oct-09 9818 39 24 18 7 15 15 17 16 13 6 19 9 Nov-09 9787 36 26 24 23 12 13 6 13 9 9 20 12 Dec-09 10528 23 30 20 22 25 15 15 15 16 12 16 11 Jan-10 10644 5 33 23 25 22 30 18 15 14 19 14 19 Feb-10 11321 1 31 23 27 24 24 11 13 22 11 16 Mar-10 11332 5 27 26 20 29 38 17 14 19 12 Apr-10 116
15、74 2 33 28 26 26 16 19 19 12 May-10 12151 4 27 27 28 31 18 13 24 Jun-10 12460 1 31 26 28 26 22 15 Jul-10 13494 1 35 25 32 35 16 Aug-10 13670 5 33 25 28 21 Sep-10 13933 4 30 23 32 Oct-10 13725 4 34 22 Nov-10 14467 3 36 Dec-10 14905 4 Total Returns Received In Month: 355 335 366 374 398 397 414 445 44
16、9 449 476 463Field Return (FR) Examples FR Examples 7-4 Table 7.2-2 shows shipments for July 2008 through December 2010, plus all shipments prior to July 2008. In addition, it shows returns for January 2010 through December 2010, by month of shipment as determined by shipping records. The highlighte
17、d first column of data in Table 7.2-2 shows the month of shipment for the 355 returns received during January 2010. For example, in January 2010, 22 returns were received from the 8253 units shipped in July 2008 and 11 returns were received from the 9243 units shipped in August 2008. The Early Retur
18、n Index, ERI, for the month of January 2010, is calculated as follows. The field population is determined by adding the shipment quantities shown on the left side of Table 7.2-2 for the months of July 2009 through December 2009. Therefore the total shipments are FRsi = 8833+8954+9368+9818+9787+10528
19、 = 57,288. The number of returned units is the total returned from July 2009 through January 2010. Therefore FRri = 14+16+20+39+36+23+5 = 153. Early Returns of units shipped Jul-09 through Jan-10 Return = 100 x 12 x Index Total Shipments for Jul-09 through Dec-09 = 100 x 12 x FRri/FRsi = 100 x 12 x
20、153/57288 = 3.20% Note that the returns of units shipped in January are included to count all returns during the month and to be alerted to any developing problems. However, shipments during January are excluded because the majority of units shipped in January will not have been placed in operation.
21、 The One-Year Return Rate, YRR, for January 2010, is calculated as follows. The field population is determined by adding the shipment quantities shown on the left side of Table 7.2-2 for the months of July 2008 through June 2009. Therefore the total shipments are FRsy = 8253+9243+9261+9721+10131+101
22、40+ 6263+6436+7244+7275+7396+8263 = 99626. The number of returned units is the total returned from units shipped in July 2008 through June 2009. Therefore FRry = 22+11+17+19+16+24+11+7+14+10+6+6 = 163. Field Return (FR) Examples FR Examples 7-5 One-Year Returns of units shipped Jul-08 through Jun-09
23、 Return = 100 x 12 x Rate Total Shipments for Jul-08 through Jun-09 = 100 x 12 x FRry/FRsy = 100 x 12 x 163/99626 = 1.96% The Long Term Return Rate, LTR, for January 2010, is calculated as follows. The field population is determined by summing the shipment quantities shown on the left side of Table
24、7.2-2 for the months prior to July 2008. Therefore the total shipments are FRst = 30,000. The number of returned units is the total returned from units shipped prior to July 2008. Therefore FRrt = 39. Long-Term Returns from shipments prior to Jul-08 Return = 100 x 12 x Rate Total Shipments prior to
25、Jul-08 = 100 x 12 x FRrt/FRst = 100 x 12 x 39/30000 = 1.56% Calculating the return rates for all months in 2010 gives Month in 2010 Early Return Index One-Year Return Rate Long-Term Return Rate January 3.20% 1.96% 1.56% February 2.80% 1.72% 1.66% March 2.66% 1.96% 1.69% April 2.44% 1.96% 1.73% May 2
26、.74% 1.86% 1.70% June 2.57% 1.65% 1.80% July 2.69% 1.50% 1.84% August 2.80% 1.81% 1.52% September 2.47% 1.55% 1.86% October 2.39% 1.55% 1.66% November 2.39% 1.73% 1.56% December 2.14% 1.57% 1.55% 2) Field Replaceable Unit (FRU) Returns Data Table The data reported to the TL 9000 Administrator are sh
27、own in Table 7.2-3. Field Return (FR) Examples FR Examples 7-6 Table 7.2-3 Example 1 FR Data Table Report Identifier Value Year 2010 Month 01 Product Category 1.1 MeasurementID FR FRa 12 FRs 99626 FRri 153 FRry 163 FRrt 39 FRsi 57288 FRsy 99626 FRst 30000 7.3 Examples With Normalization Example 7.3-
28、1 Normalized One-Year Return Rate DSL An organization makes an HDSL transmission system consisting of the following products: i) HDSL Central Office Transceiver Unit (HTU-C) One HTU-C is required per HDSL line deployed. ii) HDSL Remote Transceiver Unit (HTU-R) One HTU-R is required per HDSL line dep
29、loyed. iii) HDSL Range Extender (HRE) Zero to two HREs may be used per HDSL line deployed. iv) HDSL Fuse / Alarm Controller (HFAC) One HFAC is required per HDSL shelf, which may be used to deploy up to 13 HDSL lines. v) HDSL Central Office Terminal Controller (HCOT-CTL) One HCOT-CTL can control up t
30、o 100 shelves. vi) HDSL E220 Shelf One shelf can accommodate up to 13 HDSL transceiver units. Only products i) through v) are field replaceable units. To calculate the NYR, returns are aggregated for the entire HDSL product category and the normalizing factor is applied to the category as a whole: i
31、) HDSL Central Office Transceiver Unit (HTU-C) Returns in the reporting period (one month): 50 Shipments in the basis period (one year): 100,000 ii) HDSL Remote Transceiver Unit (HTU-R) Returns in the reporting period: 40 Shipments in the basis period: 100,000 iii) HDSL Range Extender Returns in the
32、 reporting period: 5 Shipments in the basis period: 50,000 iv) HDSL Fuse/Alarm Controller Returns in the reporting period: 3 Shipments in the basis period: 10,000 Field Return (FR) Examples FR Examples 7-7 v) HDSL Central Office Terminal Controller Returns in the reporting period: 0 Shipments in the
33、 basis period: 500 The normalizing factor for xDSL products is the number of DSL lines deployed. Since one HTU-C and one HTU-R are required to deploy a single HDSL line, the total number of lines deployed in the basis period is FRs = 100,000. The number of returns from the units shipped in the One-Y
34、ear basis-shipping period is FRry = 50 + 40 + 5 + 3 + 0 = 98. The normalized One-Year Return Rate is NYR = 12 x FRry/FRs = 12 x 98/100,000 = 0.012 returns / year / DSL line. Example 7.3-2 Normalized One-Year Return Rate Terminations An organization makes a local switch consisting of the following pr
35、oducts: i) POTS line card Each POTS line card has 16 POTS lines. ii) Trunk line card Each trunk line card has four trunk lines. iii) ISDN line card Each ISDN line card has eight basic rate ISDN lines, each of which has two terminations. Each ISDN line card has an identical card providing protection
36、for the first card. iv) Miscellaneous circuit packs Besides the previous three circuit packs there are 30 other pack codes. They do not supply termination service, but are needed to support the office. During the basis period for the YRR and NYR, this organization installed one switch with the line
37、cards and other circuit packs listed below. To calculate the YRR and NYR, returns are aggregated for the entire switch and the normalizing factor is applied to the category as a whole. i) POTS Line Card Returns in the reporting period (one month): 10 Shipments in the basis period (one year): 1,000 i
38、i) Trunk Line Card Returns in the reporting period: 5 Shipments in the basis period: 500 Field Return (FR) Examples FR Examples 7-8 iii) ISDN Line Card Returns in the reporting period: 2 Shipments in the basis period: 500 Active cards with 1:1 protection: 250 iv) Miscellaneous Circuit Packs Returns
39、in the reporting period: 2 Shipments in the basis period: 500 The normalizing factor for Switching and Routing System Elements is one termination. The total of all terminations for this switch is FRs = (1,000 x 16) + (500 x 4) + (250 x 8 x 2) = 22,000. The number for FRUs shipped in the NYR basis-sh
40、ipping period is FRsy = 1,000 + 500 + 500 + 500 = 2,500 The number of returns is FRry = 10 + 5 + 2 + 2 = 19 The Normalized One-Year Return Rate for the switch circuit pack shipments is NYR = 12 x FRry/FRs = 12 x 19/22,000 = 0.010364 returns / year / termination. The One-Year Return Rate for the swit
41、ch is YRR = 100 x 12 x FRry/FRsy = 100 x 12 x 19/2500 = 9.12%. The data reported to the TL 9000 Administrator are shown in Table 7.3-1. For completeness, the report includes examples of ERI and LTR data, which were not discussed in the example. Field Return (FR) Examples FR Examples 7-9 Table 7.3-1
42、FR Data Table Report Identifier Value Year 2010 Month 01 Product Category 1.1 MeasurementID FR FRa 12 FRs 22000 FRri 14 FRry 19 FRrt 30 FRsi 1200 FRsy 2250 FRst 4500 Example 7.3-3 Normalized One-Year Return Rate DS1 The following example demonstrates the calculation of NPRs for Product Category 3.2.
43、1.2 Digital Cross Connects where the normalization factor is DS1s. Definitions Please refer to the Glossary for definitions for NYR, Afactor, FRry, FRS, and NU. Example An organization provides a digital cross connect system consisting of the following: 1. 28 DS1 Ports 2. 256 DS3 Ports During the ba
44、sis period for the Normalized One-Year Return Rate (NYR) this organization installed twenty systems. To calculate the NYR, returns are aggregated for the entire system and the normalizing factor is applied to the overall usable port connections as a whole. ! Normalization units (NUs) per system = 28
45、 + 256*28 = 7,196 Note: This calculation determines the normalization units for the total number of DS1 Ports ! Total NUs = 20 * 7,196 = 143,920 ! FRU returns in the reporting calendar month = 22 NYR Calculation: ! Afactor = 12 ! FRry = 22 ! FRS = 143,920 Field Return (FR) Examples FR Examples 7-10
46、NYR = 12 X FRry/FRS = 12 X (22/143,920) = 12 X 0.000152863 = 0.00183435 returns/ DS1/ Year 7.4 Estimation of Equivalent Number of Normalization Units a) Problem The normalization factor for the Normalized One-Year Return Rate (NYR) is the number of normalization units that fall within the One-Year R
47、eturn Rate (YRR) shipment period. This can lead to a problem for mature products. At some point in the life cycle of many products, the new hardware being shipped is used to fill out or expand existing systems and not to create new systems or capacity growth. This can lead to a situation where the p
48、roduct has a substantial YRR Field Replaceable Unit (FRU) population, but few or even no new systems or capacity shipped in the YRR period. This then leads to a greatly distorted normalization factor. It could even become non-reportable if it was zero. The following provides a method to estimate an
49、equivalent FRs for Network Elements of capacity-based normalization using the YRR FRU population. This in turn allows the calculation of a reasonable and comparable NYR figure. b) Solution This method yields an estimated “equivalent” number of Normalization Units for reporting as the NYR normalization factor (FRs) for products subject to the problem described above. The estimate is based on other TL 9000 data elements. These
