Preferential Telecommunications Service Access Networks

1
Preferential Telecommunications ServiceAccess
Networks
FORUM ON NEXT GENERATION STANDARDIZATION
(Colombo, Sri Lanka, 7-10 April 2009)?

• Lakshmi Raman,
• Senior Staff Engineer Intellectual Ventures
• USA

2
Overview

• Preferential Telecommunications Service
• NGN considerations for PTS
• Capabilities and Mechanisms to support PTS
• Requirements for PTS in NGN Access Networks
• Signaling and Control support in Cable Access
• ITU Recommendations in support of PTS

Emergency Telecommunications and Preferential
Telecommunications are used to represent the
concept in different ITU Recommendations.
3
PTS Overview

• Preferential Telecommunications Service
• Characteristics
• Categories
• Considerations with NGN versus Circuit-Switched
  Network Environments

4
PTS Characteristics

• Assured capabilities to enable operations in the
  event of impacts to Telecommunications
  infrastructures
• Examples of PTS
• Telecommunications for disaster relief
• National/Regional/Local Emergency/Public Safety
• Early Warning Systems to individuals exposed to
  hazards to avoid or reduce risks
• Categories
• Individual to authority
• Authority to individual
• Authority to authority
• Individual to individual

ETS ITU Recommendation focuses on authority to
authority
5
NGN versus Circuit Switched Environment
Provisioning of PTS capabilities is not entirely
straightforward, obvious or simple. A simple
transposition from the circuit-switched world is
not appropriate.
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Capabilities and Requirements

• Enhanced priority treatment
• Secure networks
• Location Confidentiality
• Service Restoration Priority
• Network connectivity
• Interoperability
• Mobility
• Ubiquitous coverage
• Survivability/endurability
• Real-time transmission to support
  voice/real-time text and video/imagery(where
  bandwidth is available)?
• Non-real-time transmission to supportmessages /
  non-real-time streams (audio/video)?
• Scaleable bandwidth
• Reliability/availability

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Mechanisms

• Identification and marking of the PTS traffic
• Example mechanisms in Service Stratum SIP
  Resource Priority header,call priority designator
  in ITU-T H460.4.priority indicator in H 248.1
• Admission control policy
• Allowing requests from PTS traffic over regular
  traffic
• Bandwidth allocation policy
• Example in Transport Stratum Resource
  Reservation Protocol, DSCP code points
• Authentication and authorization of bona-fide PTS
  users
• Use of PINs, user and subscription profiles

8
Access Networks Requirements

• Different Access Technologies
• Cable,xDSL, Wireless,optical
• Signaling and Control Requirements
• Recognize PTS traffic
• Provide preferential/priority access to
  resources/facilities
• May require mapping of security levels when
  different values are used in different domains
• Support preferential/priority routing of PTS
  traffic
• Preferential/priority establishment PTS
  sessions/calls

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Access Networks Requirements (2)?

• Security Considerations
• Protecting all aspects of PTS, signaling and
  control, bearer/media, and management related
  data and information
• Establishment and enforcement of security
  policies and practices that are specific to PTS
• Authentication users with priority to prevent
  denial of service attacks by non authorized users
• A minimum of two mechanisms recommended for
  IPCablecom networks
• Implementation of mitigation capabilities to
  provide protection against various security
  threats
• Protecting end-to-end communications when
  traversing multiple provider domains

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Priority Mechanisms for IPCablecom2 Networks

• Priority Labeling
• RTP does not provide support for labeling packets
• Priority Signaling
• SIP Resource Priority header in the user agent
• Two options are possible
• SIP UA include the R-P Header
• Proxy Call Serving Control Function (P-CSCF)
  translates a code value to appropriate R-P Header
  value
• Priority Enabling Mechanisms
• Data link layer support for DOCSIS Service Flows
  according to traffic priority set for PTS
  sessions
• Session layer status set up propagating the
  priority status to all relevant entities in the
  network

11
Example Call Flow in IPCablecom 2 networks
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PTS/ETS NGN ITU-Recommendations

• ITU-T Y.1271, Framework(s) on Network
  requirements and capabilities to support
  emergency telecommunications over evolving
  circuit and packet switched networks
• ITU-T Y.2205, Next Generation Networks, Emergency
  Telecommunications- Technical Considerations
• ITU-T H.460.4, Call priority designation and
  country/international network of call origination
  identification for H.323 Priority calls
• ITU-T H.248.1, Gateway control protocol Version
  3.
• ITU-T Y.2111, Resource and admission control
  functions in Next Generation Networks.
• ITU-T J.260, Requirements for Preferential
  Telecommunications over IPCablecom networks
• ITU-T J.261, Framework for implementing
  preferential telecommunications in IPCablecom
  networks
• ITU-T J.262, Specifications for Authentication in
  Preferential Telecommunications over IPCablecom2
  networks
• ITU-T J.263, Specifications for Priority in
  Preferential Telecommunications over IPCablecom2
  networks