The Network of Information:
Architecture and Applications
SAIL – Scalable and Adaptable Internet Solutions
Bengt Ahlgren et. al.
2011
Presented by wshin 2012-05-21
Agenda
• Architectural Elements
– Transport
– Caching
– Security
– API
• Applications
– Localized CDN
– Events with large crowd
Transport
• NetInf Transport Service (NTS)
• Chunk-based request/delivery enables
Receiver-Driven Transport
• Multi-point communication
• Two approaches
– Convergence layer providing chunk request and
transport services
– End-to-End transport protocols
Transport: Chunking
• Chunk
– Application data units(ADUs) such as video frames
– A fragment of a bigger IO
– Smallest addressable and verifiable unit
• Static objects:
– Provides a way to split and move through multiple
paths.
– Failure exclusion (with per chunk auth)
– Caching
• Dynamic objects:
– Pre authentication before receiving all the chunks
Transport: Receiver-Driven Transport
• Receiver Driven
– Requester requests IOs / Publisher providing
(chunks of) such IOs
– Multiple NetInf nodes can attempt to fulfill such
requests.
• Caching
– on-path cache having chunks responds
– on-path nodes without chunks caches them
Transport: Multipoint to Point
• Path Selection
– Choice depends on performance
(Attained throughput, response time)
– These information is updated by the receiver.
• Joint “path selection and rate control”
– Receiver manages the use of available routes and
load balances. (Receiver determined multi-path)
Transport: Multicast
• Request de-duplication / Data duplication
– Request aggregation / duplication by each nodes
– Requires state to remember up / down paths
• MDHT based multicast
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NRS feature
MDHT used as a multicast distribution tree
Multicast session ID distributed into MDHT
MDHT constructs a shared distribution tree (Request
aggregated, data duplicated)
NTS Convergence Layer
• Rationale
– Multi-domain / multi-technology approach
• Convergence Layers
– An abstraction layer covering various domains and
transport mechanisms.
– A cross-domain transport layer.
– Convergence layer adaptor
– Chunk request publish / Store forward
NTS end-to-end approach
• Shortcomings of the Convergence Layer
– Out of order chunk transmission requires state mgmt
• Stateless End-to-end transport session
– State is maintained at the endpoints
– Intermediate nodes are relieved from all the
operations above.
– Caching can only be done in the resolution nodes
and/or in the edge nodes.
NTS end-to-end approach
• A receiver-based congestion control
– Rate Control Protocol (RCP)
• NetInf packets carries RCP congestion headers (RTT,
Desired rate, Feedback rate)
– Congestion control is receiver-oriented
• Data receive trigger the progression of the congestion
window and provide the rate feedback.
– Throughput: Ratio of the congestion window size
to the flow RTT
Caching
• Cache Management
• Proactive Caching
• Caching in DTN
Caching: Management
• Tradeoffs
– Efficiency determined by various performance
metrics.
– Placement
• Popularity based model
– Hit rate
• Bandwidth-lookup / Latency-hit model
– Cooperated caches
– Bandwidth required for signalling vs hits
Caching: Proactive caching
• Proactive data placement
– For efficiency
• Monitoring function
– subscriptions monitored
• Proactive client function
– Remotely instructed by the monitoring function to
subscribe a new content.
Caching in DTN
• Caching method using existing DTN facilities
• Make use of the bundle protocol (store-andforward networking)
– Custody request: from the sender to request each
nodes in the path to answer any retransmission
requests
– Bundle Protocol Query extension : Information
already in the DTN can be queried (Directing DTN
cached data requests to be responded)
– Both Handled by a node or by the DTN gateway.
Security:
Threats and Countermeasures
[Threats]
* Content Mismatch[CM]
* Content Snooping [CS]
* Privacy Invasion [PI]
* False Content Injection [FC]
* Unauthorized access [UA]
* Cache Pollution [CP]
* False accusation [FA]
* Mis-Routing [MR]
Hash based verification
PKI
XKMS
DANE
CCN style adhoc PKI
Kerberos like key sharing
“Integration of above”
API
Basic primitives (operations for NetInf layer communications)
Applications:
Localized CDN
• Overview
– Next Generation Mobile Communications
Networks
– User generated content use case
• Implementation
– Local / Global NRSs :
Rendezvous's scoped publishing
– Proactive cache : Places data close to the clients
Applications:
Localized CDN
Applications:
Event with Large Crowds
• Events with large crowds
– Large crowds subscribing events
with limited uplink bandwidth
• Nodes create an ad-hoc mesh network
– Bluetooth, WiFi and other suitable tech.
• Exploits
– Caching
– Broadcasting and link sharing
Summary
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ICN realization effort (Project SAIL)
Architectural Elements
Integration of previous approaches
Adaptive approach
Prototyping and verification
Standardization