Developing Cable Telephony Solutions

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(No Transcript)
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Developing Cable Telephony Solutions
Michael MetzgerExecutive Director,
MarketingMindspeed Technologies, Inc.
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Agenda

• Introduction
• Voice over Cable Architectures
• Cable Standardization Bodies
• High Density Cable Gateway SoC Solutions
• EMTA SoC Solutions
• Whats Next in Voice over Cable?

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Introduction

• VoIP over Cable is experiencing strong growth
  within North America
• Forecast of more than 17 M Voice over Cable
  subscribers in 2008
• VoIP over Cable completes MSOs offering for
  triple-play voice, video, and data services
• Fundamental change in architectures moving to
  Packet-based networks from analog Voice over
  Cable

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Voice over Cable Current Architecture
Headend
Class 5 Switch
Cable Modem
Network Interface Terminal
IP Network

• Analog voice traffic placed on cable medium, and
  connected to PSTN using traditional Class-5 switch

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Next Generation VoIP over Cable
CMTS
Data/Voice Traffic
IP Network
Call Mgmt Server
Voice Traffic
SBC
EMTA
IP Network
Media GW, Signaling GW
WiFi

• True VoIP over Cable, packetized in converged MTA
  solutions
• Migration to all IP networks

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PacketCable

• Specification forum focused around detailing the
  architecture for next-generation IP Cable
  networks
• For Voice, PacketCable details
• QoS
• Security
• PSTN IP Interconnect
• Lawful Intercept
• Reliability

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IPCablecom Standardization Process
Global Standards (J.160 J.174)
ITU-T
Regional Standards
SCTE
TCC (Japan)
ETSI
Contributors
CableLabs (projects)
ECCA (requirements)
Vendor
Vendor
Vendor
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PacketCable Timeline

• Rel 1.0
• Architectural framework for Packet-based Cable
  networks (1999)
• Rel. 1.5
• Added new voice codecs, fax relay (2005)
• Future Releases
• IMS architecture mobility
• Call control moving to SIP
• New voice and video codecs

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PacketCable QoS

• Quality of Service in PacketCable networks must
  at a minimum be equal to that of the PSTN
• Fundamental requirement to drive adoption
• Major Factors affecting QoS for voice
• Voice Compression Technology
• Packet Loss
• Packet Latency/Delay
• Echo Cancellation
• To ensure high QoS, SoCs must address the above

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Typical High-Density Gateway Solution
Control and Signaling
Media Stream Processing
Ethernet
Ethernet
Voice Channels
DSP Resource Manager
Control Applications
TDM
Signaling Stacks
N x DSP
Host Operating System
Internal Memory
Media Stream Processing sub-system offloads host
CPU
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SoC Solutions for High Density Gateways
VoIP to TDM (with/without encryption)
Media Forking for CALEA (with/without encryption)
Transcoding (IP-IP) (with/without encryption)
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SoC Architectures for High Density Gateways
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DSP Functions Codecs

• Limited uplink speed demands complex voice codecs
• Echo Cancellation G.168-2002/4
• Required G.711, recommended G.729e, G.728 (Rel.
  1.0)
• Added required iLBC, BV-16 (Rel. 1.5)
• Future release
• Wide-Band Codecs
• Wireless Codecs

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Example of Wireline/Wireless Codec SMV

• Selectable Mode Voice Codec (SMV) Standardized
  for CDMA2000
• G.711 Equivalent Voice Quality
• Music Detection
• Efficient Rate Determination Algorithm Average
  Bitrate 4kbit/s
• 4 coding rates (full-rate8.5kb/s, half-rate
  4.0kb/s, quarter-rate 2.0kb/s, eight-rate
  0.8kb/s)

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DSP Functions Intelligent Transcoding

• Increasing demand for Voice transcoding with
  migration to an all IP network
• Dynamic prediction algorithms prevent the
  degradation of voice quality inherent in typical
  G.711 transcoding schemes
• Roundtrip delay critical for voice quality over
  an IP network is significantly minimized
• No echo cancellation required

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Fax Modems Transport

• Required Packet DSP functions
• Transmit V.90 and 14.4 kbit/s FAX (over G.711)
• T.38 Fax Relay
• 40 ms frame sizes
• Packet redundancy
• Synchronization of end-points less than 0.25
  frame slips per minute

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Security Processing

• PSTN security is based around the assumption that
  there is a direct dedicated link between the user
  and the central office
• In PacketCable networks, shared medium is used
• As such, cryptographic methods are used to
  provide security in PacketCable for call privacy
• Optional implementation
• 128-bit AES encryption
• MMH/SHA-1 for message authentication

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Packet Cable Voice Payload Encryption
IP
UDP
Voice payload
Authentication
RTP
Encrypted Portion (AES)
Authenticated Portion (MMH)
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5 x 9s Reliability with N1 Redundancy
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Low to Medium Density MTAs
Embedded MTA
SoC
SHM
T S I
Control Signaling Processor
CSP
1 to N Telephones
Voice Data Routing
MSP
Telephony Interfaces
CablePHY
Voice DSP core
EXPANSION BUS
PCI
Wi-Fi
Printer or Peripheral
USB 2.0
MMU
Dual EMAC
Security
Ethernet
Memory
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CSP MSP Model

• Deterministic Voice Quality Data Routing/VPN
  Performance
• MSP/CSP partitioning for real-time non
  real-time processes
• Corner case interoperability standards
  compliance
• CODECs common functions run on MSP
• New/3rd Party Applications does not affect MSP
  Processing
• CSP hosts applications independent of media
  stream
• E.g Linux or VxWorks

Single UnifiedMemory
Non Real-time
CSP Control Signaling Processor
DDRSDRAM
Virtual EthernetDriver
Real-time
MSP Media Stream Processor
Cable Modem
Ethernet
TDM
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Open Source Applications for a CSP
Project Application Home
Linux Kernel 2.6 UNIX OS with integrated IPSec http//www.kernel.org/
Apache Web Server http//www.apache.org/
Busybox Common UNIX utilities http//www.busybox.net/
Asterisk PBX, IVR, voicemail http//www.asterisk.org/index.php?menufeatures
OpenH323 H.323 protocol http//www.openh323.org/
OpenSIP SIP user agent, proxy http//www.gnu.org/software/osip/osip.html
MGCP MGCP implementation http//www.vovida.org
Festival Lite Text-to-Speech engine http//www.speech.cs.cmu.edu/flite/
PPTP Client VPN software http//pptpclient.sourceforge.net/
iptables firewalling subsystem http//www.netfilter.org/
GNU Zebra Routing Protocol Manager http//www.zebra.org
gcc C/C Cross compiler http//gcc.gnu.org/
gdb Debugger http//sources.redhat.com/gdb/
Ethereal Network Sniffer (with MND plugin) http//www.ethereal.com/
KDevelop Flexible IDE http//www.kdevelop.org/
Telephony
Core
Networking
Development Tools
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Whats Next in Voice over Cable?

• Mobility
• Support cellular handset/WLAN
• Wireless/Wireline Transcoding in Cable GW
• Call control mechanisms
• TGCP ? SIP
• Migration to IP V6
• Integration of Session Border Controllers
  functions into Cable GW
• Adoption of IMS Architecture
• Instant messaging (IM)