Multimedia over DSL

1
Multimedia over DSL

• By Phil Moy

2
Agenda

• DSL Forum Working Text 80 - Multiservice
  Architecture Framework Requirements
• DSL Forum Working Text 81 - Architecture
  Requirements for the Support of QOS Enabled IP
  Services
• BRAS (Broadband Remote Access Server)
• Packet Processing
• Differentiated Services
• Current Industry Trends

3
BRAS Architecture Overview
Central Office Wiring Center
PSTN
ISPs / Internet
Class 5
Voice Gateway
ATM or Ethernet
L3 Switch /IPSS
Applications(eg, VPN)
BRAS
Video Server
Storage
ATM DSLAMs
Communications Portal
RT DSLAMs
MTU DSLAMs
4
WT-080 Multiservice Architecture Framework
Requirements

• IP QOS
• Guaranteed QOS
• ATM CAC (Call Admission Control)
• CBR
• VBR
• RSVP reservation
• Bandwidth On Demand, Turbo Button
• DSL Trained to maximum, allows dynamic control of
  rate
• Many To Many Access
• Content Distribution
• Caching
• IP Multicasting

5
WT-080 Multiservice Architecture Framework
Requirements (cont)

• Bandwidth
• ADSL - 8 Mbps up to 10,000 feet
• ADSL2 - will provide 8 Mbps with a longer range
• ADSL2 - doubles the bandwidth over ADSL but with
  half the range
• VDSL - 12.96Mbps at 1000 ft, 51.84 Mbps at 4500
  ft

6
WT-081 DSL Evolution - Architecture Requirements
for the Support of QOS Enabled IP Services

• Many to Many supported by TVR (Transparent
  Virtual Routing)
• QOS - Diffserv
• DSCP Marking of IP Header TOS Byte (6 bits)
• AF - Assured Forwarding
• EF - Expedited Forwarding
• BE - Best Effort
• Hierarchical Scheduling
• Schedule Traffic Downstream taking into account
  all physical links to subscriber
• Fragmentation
• Fragment Low Priority Packets to minimize
  delay/jitter

7
BRAS Packet Processing
. . .
Cells
Ingress
Egress
8
BRAS Differentiated Services
DS3
BRAS
Switch
Aggregation Group 1(IP)
ATM WAN
DSL
CPE Router with NAT, or Ethernet Modem, or IAD
DSL
Aggregation Group 2

• New gaming service
• One VC serves multiple subscribers
• ATM QoS thru backbone
• Policies determine which subscribers can access
  service
• IP DiffServ CoS mapped to ATM QoS

OC-3
Aggregation Group 3
Best effort to Serv Provider 1
Guaranteed to Serv Provider 1
Best effort to Serv Provider 2
Voice over IP
9
Demo System
10
Current Industry Trends

• BRAS space is new with products developed from
  Alcatel, Cisco, Copper Mountain, Juniper, and
  Redback
• RFPs for BRAS currently out from ILECs with
  scheduled roll out as early as 4th quarter 2003
  but probably next year

11
Acknowledgments

• Copper Mountain Networks
• DSL Forum

12
Conclusion

• BRAS Architecture enables Multimedia over DSL
• BRAS allows multimedia over Dumb DSLAMs.
• Congestion usually only found in the last mile
  can now be avoided
• Turbo Button allows video on demand by
  dynamically boosting bandwidth up when a user
  purchases a movie
• Diffserv allows high priority multimedia traffic
  to coexist with low priority web traffic.
• Questions?