Openreach

1
Openreach Managed Line Checker Paul Cumbers LLU
Product Line Openreach 21/10/2008
Openreach makes every effort to ensure the
information in this report is accurate at the
time of compilation, however, Openreach does not
represent that it is complete and Communications
Providers should check with Openreach for the
latest available information. Openreach reserves
the right to modify delivery criteria and
delivery dates.
2
Current Activity

• Includes
• Updates and improvements that have been
  implemented or are in hand
• Improvements and upgrades that have been
  identified
• Ongoing analysis to understand the root causes of
  other common issues

3
Problem Categorisation and Scope

• Incorrect data, e.g. CP Name
• Missing data (or latency), e.g. line length,
  celerity line loss, capacitance
• Integrity of data, e.g. incorrect line length
• Improvements to documentation and guidance in
  terms of how MLC works and fields are derived
• Short term to fix known issues
• Complete longer term strategic review

4
Summary of Activity
CR1404 areas under review identified
improvements
CRs
Bridge Cases
CR533 Error message enrichment - Implemented,
CR532 Order not closed-Not in a release CR801
Refine incompatible list -Partially
implemented. CR1408 Haydon Wick not Blunsden
workaround - Implemented CR1404 (Identify
Upgrades) see next

• Line length
• Use measured line length over calculated
• Use average as opposed to worst case
• Line loss data
• Line characteristics (capacitance)
• Retain CELERITY data for 16 weeks
• Use access id as an additional key from Celerity
• Use service id as an additional key from Celerity
• Post Code
• Exchange not returned for selected post code
• When a post code may be served by one of two
  exchanges review logic
• Where the exchange is identified by longitude and
  latitude
• Modify the post code qualification rules

BD 768743 BD 835867 BD 846886 BD 938010 BD
965522 BD 948719 BE 005214 BE 002026
CP NAME DUNNs ID Post Code Matching MAC Validation
Cases in blue have been resolved
5
Update and Enhance Documentation

• Engender better understanding
• Use as a base-line for
• Clarifying defects
• Rationalising fields and focus on improving data
• Scoping future changes

6
MLC fields
Exchange name, short code and CSS district
combined MDF site ID, e.g. WWNABB
Not BT post code, derived from post office
address file
Distribution point, last node before the end
users premises
Access Network Frequency Plan
Estimated line lengths
Capacitance
7
Access line ID, 10 digits prefixed by district
code
MLC fields
Only provided for DP and post code searches
Values are working or stopped
Derived measure at 300kHz
Line loss calculator, uses cable records where
they exist
Only provided for DP and post code searches
Returns incompatibles
8
Post Code

• Post code information provided and updated from
  post office address file on a quarterly basis

9
DPs, overhead or underground
10
Access Network Frequency Plan

• The access network frequency plan is a spectrum
  management plan for controlling interference,
  caused by cross talk, within the metallic access
  network.
• The categorization of end users locations is in
  terms of electrical distance from the exchange,
  defined by loss values at 100kHz, from the DP to
  the exchange. The categories are
• Extra short is 21 dB or less,
• Short is 26 dB or less but over 21 dB
• Medium is 29 dB or less but over 26 dB
• Long is over 29 dB

11
Estimated Line Lengths

• Where records of all segments from the exchange
  to the DP exist these are applied - taking worst
  case where there are multiple cables between
  points
• If a segment is missing a radial distance is
  calculated using grid references.
• To get the full line length the radial distance
  between the post code mid point grid ref and the
  DP grid ref is used and added to above.

12
Real example
Local Exchange
Estimated Line Length
TW
4 5
LZ
PC Easting

513200
DP Easting

513192
PC Northing
-
173600
DP Northing
-
173644
Main Distribution
Frame
2987
meters
PCP
DP
681
meters
2838
meters
48 Meters calculated using grid reference
DP Line Length
5900
meters
Circuit Line Length

48

DP Line Length
13
Capacitance

• Result is provided in Nano-Farads
• Very rough calculation divide by 58 to get
  approximate line length in Kms

14
Celerity Line Loss

• Celerity is a test capability available from
  Openreach's exchange based test systems which
  provides line loss information. The line loss for
  an individual pair is arrived at by taking
  measurements at 45 spot frequencies up to 20KHz.
  The loss at 300Khz (which Celerity provides) is
  then inferred based on an internal algorithm.
• There are several reasons why these tests cannot
  be run including the end user requesting
  exemption, the line being busy at the time of the
  test request, or other potential test
  infrastructure failures

15
Estimated Aggregate Values

• Capacitance
• This is provided for DP and Post Code calls only
• DP value is the average value across all lines at
  the DP (ignoring extreme values)
• Post Code is the average value across all lines
  within the postcode (ignoring extreme values)
• Line Length
• This is given for DP and Post Code calls only.
• DP is the average line length across all lines at
  the DP (ignoring extreme values)
• Post Code is the average line length across all
  lines within the postcode (ignoring extreme
  values)

16
Incompatibles

• A ADSL
• D DDI
• E DACS
• F Fibre
• I ISDN/Highway
• K Line Concentrator
• L SMPF LLU Installation
• M MPF LLU Installation
• O Other network incompatible device (not
  currently used)
• P Incompatible Technology (if the installation
  product list contains an incompatible product
  code not covered by W and X below)
• T TPON
• V FeatureNet
• W Incompatible Technology - Redcare/NBLS
• X Incompatible Technology - Multiline/PBX
• Z No Reason Code No Issues

17
CP Name Issues

• Change data feed and sequence (Siebel to
  OrBIT/LODE)
• Optimise data feeds
• Inactive asset details arriving after active
  asset details, removing CP name (data
  synchronisation issue)
• Refresh baseline of current data Target end of
  November

18
Next Steps

• Update MLC section of dialogue services guide,
  including definitions
• Complete CP review and rationalisation
• Run requirements capture
• Short terms fixes, costs and timescales to be
  confirmed by 14th November
• Change retention periods for Celerity data to 16
  weeks update celerity data for stopped lines
• Design changes for CP Name (resolve data
  synchronisation issues)
• Key strategic MLC change
• Use measured line length
• Prepare business case, benefits captured and
  funding agreed
• Pending PCG (industry) approval
• Target Quarter 4 / 1 delivery

19
Back Up
20
MLC Error Message Enrichment CR 533 Example
New Codes 2177 / 78
21
CR 533 Example Portal Only Response Code
Clarification
Standard systems failure message BT/Openreach
has encountered a technical problem
Enhanced process to remove genuine business
errors from this code