User Application-to-User Plane Vertical Interface (draft-ash-nsis-vertical-interface-00.txt)

1
User Application-to-User PlaneVertical
Interface(draft-ash-nsis-vertical-interface-00.tx
t)
Jerry Ash gash_at_att.com
Al Morton acmorton_at_att.com
Martin Dolly mdolly_at_att.com
Percy Tarapore tarapore_at_att.com
Chuck Dvorak cdvorak_at_att.com
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Summary (draft-ash-nsis-vertical-interface-00.txt
)

• proposes requirements for communicating QoS
  parameters between user application layer user
  plane layer
• currently no vertical interface protocol (VIP) to
  do this
• signaling protocol assumptions
• SIP at user application layer
• QoS-NSLP at user plane layer
• illustrative example of high-priority, emergency
  telecommunications service (ETS) VoIP call flow
• protocol extensions to meet VIP requirements TBD
• adaptation of QoS-NSLP could be appropriate basis
  for VIP
• RESERVE RESPONSE messages satisfy requirements
  for VIP-request VIP-response messages
• QSPEC parameters already defined to convey
  necessary QoS parameter information
• future versions of document will specify more
  details
• next steps
• gage interest within NSIS

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Example Call Flow (draft-ash-nsis-vertical-interf
ace-00.txt)
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Example Call Flow (draft-ash-nsis-vertical-interf
ace-00.txt)

• ETS user dials 1-710-NCS-GETS to establish ETS
  VoIP call
• call routed by local exchange carrier (LEC)
  access network to service provider's GW1
• GW1 recognizes ETS call based on dialed number or
  SS7 initial address message indicator
• GW1 formulates SIP INVITE message marked with
  appropriate packet markings
• SIP with pre-conditions used to negotiate codec
  bandwidth
• RPH populated with ETS namespace, with priority
  set to "0" for highest priority (i.e., ets.0)
• GW1 infers additional QoS parameter based on info
  available at access network interface (trunk
  group characteristics, dialed number, SS7 initial
  address message, etc.)
• Y.1541 QoS class set to class 0 with stringent
  delay requirements
• DiffServ PHB set to high-priority expedited
  forwarding (EF1)
• Reservation Priority set to high
• Restoration Priority set to high

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Example Call Flow (draft-ash-nsis-vertical-interf
ace-00.txt)

• GW1 communicates QoS parameter info via VIP to
  NSIS QoS-NSLP user-plane function
• NSIS QoS-NSLP user-plane function sets upETS call
  flow withY.1541-QOSM required attributes in the
  QSPEC
• ltBandwidthgt negotiated bandwidth
• ltY.1541 QoS Classgt class 0
• ltDSTE Class Typegt class type 0
• ltReservation Prioritygt high
• ltRestoration Prioritygt high

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Next Steps

• gage interest within NSIS WG
• if interest progress draft in NSIS WG
• define adaptation of QoS-NSLP to support
  VIP-request VIP-response messages