INTERCONNECTION TRAINING WORKSHOP

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INTERCONNECTION TRAINING WORKSHOP

• Interconnection- Number Portability
• Presented By
• Emmanuel L. Amoah

Banjul, 11 15 July 2005
ITU/EC Regulatory Capacity Building Project for
ECOWAS countries
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OUTLINE

• Number portability (NP) definition
• NP services classification
• Processing a call to a ported number
• Different techniques used to implement NP
• Comparison of those techniques

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Number portability (NP)

• NP refers to the ability of end-users to retain
• their telephone number when they change
• 1. their network operator/service provider
• 2. their location
• 3. or their service.

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Classification of number portability services

• There are tree number portability services
• Operator portability
• Location portability
• Service portability

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Operator portability service

• It refers to the ability of an end user to retain
  the same telephone number when changing from one
  operator to another.
• It is also referred to as service provider
  number
• portability.
• It is further divided into
• geographic number portability for all fixed
  public telephone network and integrated services
  digital network (ISDN) subscribers at a specific
  location

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Operator portability service

• Non-geographic number portability or NGNP for
  fixed numbers at any location and
• mobile number portability or MNP.

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Location portability

• It refers to the ability of an end-user to retain
  the same telephone number when changing from one
  physical location to another without necessarily
  changing their operator.

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Service portability

• It refers to the ability of an end-user to retain
  the same telephone number when changing from one
  type of service to another without necessarily
  changing their operator.
• (e.g., from old telephone service to ISDN)

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Processing a call to a ported number

• Two stages are involved
• 1. Interception stage
• It is the recognition that the call is toward a
  ported number.
• It can be performed at
• - donor switch (local exchange where the
  subscriber line was initially
• attached before being ported),
• - transit switch,
• - originating switch (the switch from which
  the calling partys call originates).
• 2. Routing stage
• The call is re-routed from the intercepting
  switch to the new terminating
• switch.

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Intercepting at the donor switch
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Intercepting at a transit switch
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Intercepting at the originating switch
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Implementing Number portability

• Technical solutions depends on
• The time scales required
• The characteristics of the existing network
  (level of digitalisation, existence of
  Intelligent Network (IN) platforms, network
  architecture etc)
• The interconnection structure (number of POIs and
  level of
• interconnection, number of transit areas
  etc) and
• The scale of implementation of NP (very small
  number of lines
• concerned, or generalised use of this
  service) and the number of operators involved.

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Number portability-- Techniques --

• Mainly two broad categories of techniques are
  used to
• implement NP
• On-switch solution.
• Switches are changing information to look for
  destination.
• Off-switch solution.
• Involves Databases usage to pick portability
  information

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On-switch solution (1/3)--Technical scheme --

• Information is relied on the Donor local
  exchange .
• (Original local exchange)
• There is a call forwarding or tromboning to the
  Recipient
• Switch. (New local switch)

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On-switch solution (2/3)--Two main families--

• Solution Category 1 onward routing
• (call forwarding and derivatives)
• - using a second number,
• - using a generic routing number,
• - using a routing prefix,
• - transparent call forwarding (using a
  routing prefix).
• Solution Category 2 translation via routing
  tables
• - using translation into a second number,
• - using translation into a prefixed number.

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On-switch solution (3/3)--Advantages and
limitations--

• Its quick to implement,
• but it
• Produce  Tromboning , and
• Require a variable amount of software
  development in the call processing mechanisms and
  in the signalling.

• On-switch solution can be seen as a short term
  interim
• solution for Number Portability.

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Off-switch solution--Technical scheme--

• Portability information is stored into one or
  several
• external Databases.
• Intelligent Network techniques are used.
• Best routing of the call to the final
  destination.

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Off-switch solution--Advantages--

• No tromboning The query used to pick up the
• information portability from databases is a
  signalling
• connection, not a traffic connection.
• More adequate solution than On-switch one.

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TRAINING WORKSHOP ON NETWORKS AND SERVICES

• THANK YOU FOR YOUR ATTENTION

Banjul, 11 15 July 2005
ITU/EC Regulatory Capacity Building Project for
ECOWAS countries