AMHS Performance

1
AMHS Performance
AMHS Implementation Workshop Chennai, India 15th
17th December 2008
2
List of Topics

• Concept of Performance
• Performance in Communication - RCP
• Aspects of AMHS Performance
• Performance Indicator
• Proposed Regional PI
• Other Issues

3
Concept of Performance

• A major factor in determining the overall
  productivity of a system, performance is
  primarily tied to availability, throughput and
  response time.

4
Concept of Performance

• For aviation, performance considerations are
  expected to be aligned to the end-to-end
  oriented, instead of component-oriented.
• Example
• Required Navigation Performance (RNP)
• Required Communication Performance (RCP)
• Required Surveillance Performance (RSP)

5
Concept of Performance

• Performance is tightly related to implementation
  where regional-groups have to coordinate with.
• Some aspects of performance should be left to the
  States as local matters.

6
Performance - RCP

• Required Communication Performance (RCP)
• Defined by ICAOs OPLINKP
• Defined with respect to the operational
  performance instead of the technical performance
  (technology independent)

7
Performance - RCP

• Is strongly recommended, but it is not mandatory
• is mainly defined in terms of time, especially
  response time, aspect of performance (no
  through-put aspect)
• The RCP types are defined by the ICAO (OPLINKP),
  the specific values of the RCP types are to be
  selected for any specific ATM services provided,
  e.g. Separation Assurance, by concerned groups
  for any specific airspace.

8
Performance - RCP
9
Aspects of AMHS Performance

• Objectives of AMHS Performance Assessment
• Regional Assessment of Performance
• Some Indicators of AMHS Performance
• Synonyms Quality of Service

10
Aspects of AMHS Performance

• Proposed Activities of AMHS Performance
  Assessment
• Identifying/Confirming the Performance Indicator
• Setting Performance Target (during the planning
  stage)
• Measuring Performance
• Evaluating Performance (at the operational stage)

11
Category of AMHS Performance

• Demand of messaging
• indicates the number of messages received and
  sent at each AMHS server
• Capacity of AMHS Server
• indicates the ability to handle the number of
  messages in the service.
• Time efficiency (delay)
• indicates the time interval required to transmit
  individual message.
• Reliability

12
Performance Indicators (PI)
Category Candidate Indicator
Demand of messaging Inbound (receiving) demand
Demand of messaging Outbound (sending) demand
Capacity of AMHS Throughput
Time efficiency Delays in transmission
Reliability Quality on message delivery ( of Undelivered messages)
Reliability Quality of delivered message ( of Error messages)
13
Demand of messaging

• Inbound Demand
• Number of messages an AMHS system expected to
  receive during certain interval.
• Outbound Demand
• Number of messages an AMHS system expected to
  send during certain interval
• The peak demands of inbound and outbound
  messaging may differ during the operation.

14
Demand of messaging

• The inbound message demand at one AMHS server may
  influence the transmission of other AMHS servers.
  
• The inbound/outbound demand is a good estimate of
  the capacity of the system.
• The regional messaging demands is not necessary,
  however the statistics of messaging demand as a
  whole in the region will be useful.

15
Capacity of AMHS server

• The capacity of AMHS server indicates the ability
  to handle the number of messages in the service
  (Throughput).
• It is the States responsibility to identify the
  capacity of their AMHS servers

16
Time Efficiency

• The time for transmission (delay) indicates the
  time interval required to transmit individual
  message.
• Several values can be measured
• Time from server output queue to server input
  queue
• Time from server input queue to server storage
• Time from server storage to server output queue

17
Reliability

• There are two possible AMHS performance
  indicators related to the reliability
• Quality of message delivery - how many messages
  out of the total messages sent are
  delivered/undelivered to the intended recipients
• Quality of delivered messages - how many messages
  out of the messages received have/does not have
  the (detected) errors

18
Proposed Regional PI

• Inbound Demand (at Receiver)
• Using the inbound demand at receiver, the sender
  can adjust the parameters for sending message
  accordingly.
• Quality on Message Delivery
• The number of NDRs can be indicator of this
  aspect
• Quality of Delivered Message
• The number of messages with detected errors can
  be indicator of this aspect.

19
Proposed PI For State

• At State Level Local AMHS server
• Demand both inbound and outbound demand
• Capacity using peak inbound and outbound demand
• Time Efficiency various delays value
• Reliability quality of message delivery and
  delivered messages

20
Target of PI

• All PI should have target whether they are
  regional or state.
• The target should be agreed by all members.
• For Regional PI, the indicator should be measured
  and reported periodically.
• Example
• Quality of message delivery the rate of NDRs
  message should be less than or equal to 10(-4)

21
Other issues to consider

• AMHS performance assessment during transition
  period.
• AMHS performance assessment across Regional
  boundaries.
• Performance assessment at Network/Data Link level
  (Lower level)

22
Thank you