MobiHealth Communication Infrastructure

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MobiHealthCommunication Infrastructure

• MobiHealth WP3 meeting
• September 20, 2002
• MobiHealth Team, University of Twente
• Email mhealth_at_mobihealth.org
• Internet www.mobihealth.org

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Presentation Layout

• MobiHealth Communication Infrastructure
• Communication Requirements
• How to proceed?
• Info MobiHealth testbed Netherlands

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MobiHealthCommunication Infrastructure

• Communication infrastructure for bi-directional
  multimedia data communication between a
  MobiHealth BAN and arbitrary host on the
  Internet.
• Communication infrastructure issues

• Speed
• Coverage
• Availability
• Scalability

• Mobility
• Security

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MobiHealth ExternalCommunication Environment
IEEE 802.3/11/15
IEEE 802.11/15 2.5G, 3G
IP
? Focus
2.5G, 3G
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Communication Requirements
Communication requirements are derived from the
MobiHealth system requirements. MobiHealth
system - application, BANOS, BAN

• GPRS or UMTS as bearer service (mandatory)
• IP network protocol (Internet standard)
• Performance (e.g. goodput speed, delaymax)
• Coverage (GPRS and/or UMTS)
• Reliability (e.g. packet loss, availability)
• Traffic management (e.g. prioritization of data)
• Mobility of a BAN (network node)
• Security (e.g. authentication, authorization,
  encryption)

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Communication Requirements (cont.)

• Performance
• Depends on BAN application MobiHealth trials
• example MST trauma team
• Bandwidthu peak(ti30) 236 kbps, sustained
  20-100 kbps
• Bandwidthd 64-256 kbps
• Max speed E2E connection speed slowest segment
• GPRS 14-112 kbps (CS2 coding)
• UMTS 64-144 kbps
• High delay between transmission and receipt of a
  packet
• GPRS 1500ms avg. (ICMP) roundtrip delay
• UMTS ???

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Communication Requirements (cont.)

• Coverage (GPRS and/or UMTS)
• Depends on BAN application MobiHealth trials
• example
• City of Barcelona (ES), Lulea (S) region,
  Enschede (NL) city centre, Duisburg (D) region

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Communication Requirements (cont.)

• Reliability
• Transport of patient vital sign data, remote
  control of BANs.
• What to aim for? 99.999 uptime? 100 error free
  communication?
• Where to implement?
• Application Layer
• protocols http,
• Transport Layer
• CO service (TCP) E2E reliable delivery, flow
  control
• CL service (UDP) unreliable delivery, no flow
  control
• Lower Layers (Network, Link, Physical)?
• How to evaluate reliability of MobiHealth
  infrastructure?

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Communication Requirements (cont.)

• Traffic management
• Transport of patient vital sign data, remote
  control of BANs.
• Guaranteed bidirectional communication in
  congested networks
• MNO, Internet, Enterprise network,
• Mobile Network Operators No voice over data
  priority scheme!
• How to deal with traffic management in the
  MobiHealth infrastructure?

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Communication Requirements (cont.)

• Security
• Transport of personal (medical) data, remote
  control of a BAN,
• Is end-to-end (BAN-to-Internet host) security
  needed? What level? Depends on user requirements
  (WP1)!
• Security can be added to most communication
  layers!
• Different security features depending on layer
• Link layer Bluetooth, GPRS/UMTS, ...
• Network layer IPsec, ...
• Transport layer SSL/TLS, HTTPS, ...
• Application layer Data encryption (OpenSSL
  Libraries, MIME)

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Communication Requirements (cont.)

• Mobility of a BAN
• Cross border connectivity?
• Speed limitation? (e.g. MST trauma trial 80-100
  km/hr)
• Application disruption?
• How to handle handovers?

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Communication Requirements (cont.)

• Mobility of a BAN

Horizontal Handover
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Communication Requirements (cont.)

• Mobility of a BAN

Vertical Handover
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How to proceed?

• WP1 user requirements needed
• Performance, coverage, reliability, security
• WP2 system requirements needed
• Derived from WP1
• WP3 communication infrastructure requirements
• Derived from WP1 and WP2
• WP3 preliminary testing
• testdrive with plain IP E2E communication
• develop measurement strategy
• performance, reliability (incl. mobility),
  coverage, security

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MobiHealth testbed Netherlands
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Internet Layering Model

• Application Layer (L5)
• supports network applications
• protocols http, smtp, ftp,
• Transport Layer (L4)
• provides service of transporting L5 messages
  between hosts
• CO service (TCP) E2E reliable delivery, flow
  control
• CL service (UDP) unreliable delivery, no flow
  control
• Network Layer (L3)
• routing of datagrams between hosts (src/dst)
• IP, routing protocols (e.g. RIP, OSPF, BGP)
• Link Layer (L2)
• datagram transfer between adjacent network
  elements
• Ethernet, PPP
• Physical Layer (L1)
• bit transport on the wire