Active Jitter Control

1
Active Jitter Control

• Stephen F. Bush
• http//www.crd.ge.com/people/bush
• General Electric Corporate R D
• DARPA ITO
• F30602-98-C-0230 supported by the Air Force
  Research
• Laboratory/IF

2
Active Networking
Traditional Packet Network
Data
Header
Adaptive monitoring, and predictive control
Network-Aware Devices
Active Network
Header
Code
Data
Custom code injected by applications/devices makes
network intelligent
Reduces protocol deployment time from years to
months
3
Active Network Devices
Network executes data packets.
Network becomes computationally active.
NodeOS/EE
4
Impacts
Secure Virtual Private Networks

• Asset Management
• Remote Upgrades
• Self-management
• Remote fault diagnosis
• and repair

Active Network
Innovative Security Models
Fusion of media inside network

• E-Commerce
• Active negotiation
• Dynamic Coalitions

Custom services for wireless users
5
Without Network Jitter Control
BUFFER
destination
packets
receiving node
Packets bunch together and must be evened out
at receiving node.
For packets i and j D(i,j) (Rj-Sj) - (Ri - Si)
6
With Active Jitter Control
Packets delay themselves within the network to
reduce jitter.
7
Per Packet/Node Delay
Delay history is maintained in smallstate to
determine distribution. Packet delays itself to
exactly Qd time units.
8
Per Packet Decisions

• Packets know their content.
• Packets know their network environment.
• Packets make the optimal decision concerning how
  long to delay to minimize variance.

9
Finer Resolution In-Stream Control
Buffer
Buffer
NODE
NODE
Portions of image or other jitter sensitive data
can receive different levels of jitter control
within the same network stream.
10
Conclusion

• Active networks allow generic packet level
  processing within the network.
• Active networks can be used to benefit real-time
  applications.