Transcript Towards Wireless Overlay Network Architectures
ICEBERG: From POTS to PANS Anthony D. Joseph Randy H. Katz Reiner E. Ludwig B. R. Badrinath UC Berkeley
Stanford March 11, 1999 http://iceberg.cs.berkeley.edu
Bridge to the Future Cellular “Core” Network
ICEBERG:
I
nternet-based core for
CE
llular networks
BE
yond the thi
R
d
G
eneration
• June 1998 - June 2001, joint with Ericsson • High BW IP backbones plus diverse access networks – Different coverage, bandwidth, latency, and cost characteristics – Real-time services across diverse access networks – 3G cellular: UMTS/IMT2000 – Next generation wireless LANs: Bluetooth – Home networking: DSL / Cable modem
Transparent Information Access
Speech-to-Text Speech-to-Voice Attached-Email Call-to-Pager/Email Notification Email-to-Speech All compositions of the above!
Universal Inbox Policy-based Location-based Activity-based Empower users!
Smart Spaces
• Walk into a A/V room and control
everything with your own wireless PDA
– Services for each device – Automated discovery and use – Automated UI generation – Composite behaviors • Phones as well as PDAs – Speech-enabled control
Potentially Any Network Service (PANS)
Same service in different networks Service handoff between networks 2-way Paging GSM/CDMA IAP PSTN IAP IAP E.g., “follow me” service E.g., any-to-any service
High BW IP core Diverse access links
IP IAP WIP IAP Iceberg Access Points (More than gateways) • Impedance matching • Provide policy engine • Handles routing, security
Important Trends
• Multimedia / Voice over IP networks – Lower cost, more flexible packet-switching core network – Simultaneous delay sensitive and delay insensitive flows
(RSVP, Class-based Queuing, Link Scheduling)
• Intelligence shifts to the network edges – User-implemented functionality • Programmable intelligence inside the network – Proxy servers intermixed with switching infrastructure – TACC model & Java code: “write once, run anywhere” – Rapid new service development, Speech-based services – New challenges for network security and management • Cellular networks for the 21st century – High BW data (384 Kb/s-2 Mb/s): Reliable Link Protocols
ICEBERG Project Goals
• Demonstrate ease of new service deployment – Packet voice for computer-telephony integration – Speech- and location-enabled applications – Complete interoperation of speech, text, fax/image across the
four P’s: PDAs, pads, pagers, phones)
– Encapsulating legacy servers and supporting new, “thin” clients • Demonstrate new system architecture to support
innovative applications
– Personal Information Management » Universal Messaging: e-mail, news, fax, voice mail » Notification redirection: e.g., e-mail, pager – Home networking and control of “smart” spaces » Build on experience with A/V equipped rooms in Soda Hall,
transfer to home environment
ICEBERG Project Goals
• Understand the implications for cellular network
design based on IP technology
– Cellular / IP interworking functionality – Scalability: 100,000s of simultaneous users in the SF Bay Area – “Soft” QoS for wide-area, delay-sensitive flows • Understand how to securely – Encapsulate existing applications services like speech-to-text – Deploy and manage computational resources in the network – Integrate other kinds of services, like mobility and redirection,
inside the network
Outline
• Example Services • Trends and Goals • Experimental Testbed • Project Approach • Research Areas – Cellular / IP integration – Wireless link management – Multi-modal services • Summary
Experimental Testbed
Velo IBM WorkPad Nino MC-16 CF788 Motorola Pagewriter 2000
306 Soda 405 Soda 326 Soda “Colab”
TCI @Home GSM BTS WLAN / Bluetooth Pager SimMillennium Network Infrastructure H.323
GW Smart Spaces Personal Information Management Millennium Cluster Millennium Cluster
Project Approach
• Make it real: build a large-scale testbed – Time travel: bring the future to the present – Collect “real” information about systems – Users develop new/interesting applications • Understanding three key research areas – Cellular / IP integration: Mobility Management, Universal Inbox – Wireless link management » Packet Scheduling in GPRS/W-CDMA, Reliable Link Protocols – Multi-modal services: Speech control / Information dissemination • ProActive Infrastructure: NINJA – Computing resources spread among switching infrastructure – Computationally intensive services: e.g., voice-to-text – Service/server discovery, security, authentication, and billing
Internet-Scale Systems Research Group
5 faculty, ~35 students Personal Information Management and “Smart Spaces” Distributed Videoconferencing Room-scale Collaboration Speech and Location Aware Applications ICEBERG Computer-Telephony Services MASH Media Processing Services Active Services Architecture TranSend Extensible Proxy Services Distributed Computing Services: NINJA Computing and Communications Platform: Millennium/NOW
Outline
• Example Services • Trends and Goals • Experimental Testbed • Project Approach • Research Areas – New service requirements: Multi-modal user interfaces – Generalized Information Redirection – Cellular / IP integration – Wireless link management • Summary
New Service Requirements
• Encapsulation of complex data transformations – Speech-to-text, text-to-speech • Dynamic service composition – Voice mail-to-email, email-to-voice mail • Location-aware information services – E.g., traffic reports • Multicast-enabled information services – Multilayered multicast: increasing level of detail as number
of subscribed layers increases
– Reliable information delivery over low bandwidth links
Multi-Modal User Interfaces
• Speech is the ubiquitous access method – Access from millions of phones (analog to digital cellular) • Rapid support for new devices (new device in 2 hrs!)
IP-Pad (BTS)
Gateway
Cell Phone
RTP
Entity
Barbara
RMI
Simja Server
RMI
Service Entity
Room Control
UDP
Room (MASH)
Entity
Emre
Interactive Voice Response to A/V Devices Application
• Dynamic data transcoding – Source and target data format independence / isolation Audio Microphone Cell phone
Automatic Path Creation
ICSI Speech Recognizer Text NLP Cmd Room Entity
Control/Metadata
A/V Devices
Response to Client
Generalized Redirection Agents
• Users (will) have many communication devices • Dynamic policy-based redirection – User- or service-specified policies – Universal Inbox: 1-800 service, email to pagers, etc. – Use APC to perform dynamic data transcoding • Service mobility as a first class object
Service Mobility as a First-Class Object
Universal Names: Globally unique IDs
“Anthony@Berkeley”
An Entity has a universal name and a profile; Entities are people, services or processes
OfficePSTN: 510-643-7212 FaxPSTN: 510-643-7352 DeskIP: rover.cs.berkeley.edu:555 LaptopIP: fido.cs.berkeley.edu:555 PCS: 510-555-7212 E-mail: [email protected]
Home: 510-555-1212
Profile: set of domain-specific names
Iceberg Inter-Domain Naming Protocol
IAP Call(Randy@Berkeley, Caller’s network, Interactive, CallerID certificate) IDNP Server Replicated Information: • Real-time • Lazy • Epidemic System State minutes/hours Profile weeks/months Policy days/weeks IDNP Server
E-Mail store
Universal Inbox Service
IAP 5 IAP 1
IP Core Network
Univ-Inbox Service
PSTN
IDNP Server
1
IAP 2
IDNP Server
n
GSM
IAP 4 IAP 3
Voice Mail store Laptop (VAT)
Cell-Phone to Cell-Phone
4. Create Data-Path Data Path (Null) 1. Dial Number 2. Intercept Call Univ-Inbox Service IDNP Server 3. Access Directory Service 5. Complete Call-Setup
Cell-Phone to E-Mail
4. Create Data-Path
GSM
Data Path
PCM
6. Another Path
PCM
1. Dial Number 2. Intercept Call Univ-Inbox Service IDNP Server 3. Access Directory Service Voice-mail Service 5. Complete Call-Setup
Text
--- --- --- 7. Send e-mail
Cellular / IP Integration
• Integrating a GSM BTS with an IP core network – Mapping IP signaling to SS7 radio management – Call admission and handoff • Mobility management interworking – Mobile IP uses home agent / foreign agent – GSM uses Home Location Register / Visiting Location Register – Handoff between Mobile IP and GSM networks – Scalability, security of Mobile IP?
GSM BTS-IP Integration
Interactive Voice Response
Uses OM & TRAFFIC to simulate BSC, MSC, and HLR functionality
Infocaster VAT PC NetMeeting 2 TRX RBS 2202 Control Signaling Signaling E1
UPSim
GPC board Ethernet Traffic E1: Voice @ 13kb/s Data @ 12kb/s
IP-PAD
Thor-2
Internet GSM Phone
Performs rate adaptation function of ZAK/TRAU
H.323 GW PSTN
Wireless Link Management
• Modeling GSM data links – Validated ns modeling suite, now using BONES simulator – GSM channel error models from Ericsson • QoS and link scheduling for next generation links – High Speed Circuit Switched Data (HSCSD), General Packet
Radio System (GPRS), and Wideband CDMA (W-CDMA)
– RSVP signaling integration with bottleneck link scheduling • Reliable Link Protocols – Wireless links have high error rates (> 1%) – Reliable transport protocols (TCP) interpret errors as congestion – Solution is ARQ protocol, but retransmissions introduce jitter
RLP-TCP Collection & Analysis Tools
• RLP and TCP interaction measurement / analysis – Both are reliable protocols (link and transport layers) – Trace analysis tool to determine current interaction effects – Tools for design of next generation networks (e.g., frame length)
TCP: End-to-End Reliability RLP: Wireless Reliability TCP / RLP stats
BTS
GSM Network GSM-IP Gateway RLP stats Post-processing tool (300 bytes/s) TCP stats
TCP and RLP Data Plot
Sent 30,720 bytes from mobile host to stationary host
45000 40000 35000 30000 25000 20000 15000 10000 5000 0 0 5 10 15 20
Seconds
25 30 35 40 TCP Bytes TCP Acks RLP Bytes RLP Ack
Dynamic interface - Zoom, scale - Add/delete items
Summary
• Iceberg testbed will be mostly completed by summer – Testbed will enable development of new protocols • Lots of on-going design work – Automatic path creation – Service handoff: Passing metadata across/through networks – IVR: More applications and devices (WindowsCE) – Service location and discovery » Query model and security
ICEBERG: From POTS to PANS Anthony D. Joseph Randy H. Katz Reiner E. Ludwig B. R. Badrinath UC Berkeley
Stanford March 11, 1999 http://iceberg.cs.berkeley.edu
Bridge to the Future Cellular “Core” Network