Transcript Networking Named Content Van Jacobson, Diana K. Smetters, James D. Thornton, Michael F.

Networking Named Content
Van Jacobson, Diana K. Smetters, James D. Thornton,
Michael F. Plass, Nicholas H. Briggs, Rebecca L.
Braynard
Content Centric Networking
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Network use has evolved since IP was designed
Usage of the Internet is in terms of what not
where
CCN: architecure built on named data rather than
named hosts
Provides security, scalability, performance.
Content Centric Networking
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Two packet types: Interest and Data
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Heirarchical content naming scheme
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Allows dynamic content generation: active names
CCN node has 3 components: FIB, Content Store
and PIT
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FIB: Forwarding table, allows multiple output
faces
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Content Store: Buffer, also caches Data packets
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PIT: Pending Interest Table
CCN Nodes
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Processing an Interest:
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Matching Data is found in the Content Store
=> send it and consume Interest
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Pending Interest in PIT
=> add this face to RequestingFaces list
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Use FIB to forward Interest on outgoing faces, add
to PIT
Processing Data:
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Data follows a chain if PIT entries back to the
source
Duplicate and unsolicited Data is discarded
Reliability and Flow Control
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Interests serve the role of window advertisements
Each packet is independent => TCP SACK is
implicit
Flow balance is maintained at each hop, not endto-end like TCP
Thus additional, TCP-like congestion control
mechanisms not required.
Naming Content
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Hierarchical content names with a flexible format
Individual name consists of a number of
components
Names can be relative to some known name, e.g.
next/previous
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Same content can have multiple names! Problems
with caching?
A source of data performs a Register operation for
a prefix
Routing
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Routing between CCN nodes can occur over
unmodified OSPF.
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Incremental deployment of CCN nodes is possible
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Integration with BGP is also possible
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Routers do not construct spanning trees
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Loops are not possible anyway
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Multiple paths can be used
Content Based Security
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Security travels with the content, it is not a
property of the connection
CCN authenticates name-content bindings by
signing the name and content in each data packet
Arbitrary key management schemes can be used
over CCN
Keys can be sent over CCN since they are just
another piece of data
If we trust some public keys, we can infer more
Network Security
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Sending a malicious packet to a host is difficult
because CCN talks only about content, not to
hosts
Data based DoS attacks are impossible because
only one Data packet is forwarded per Interest
Interest flooding:
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Multiple Interests for the same content are
combined
Limit the forwarding of unsuccesful interests
What if sender and receiver collude?
Evaluation
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Transfer time vs Number of Sinks
Evaluation
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Failover
An Architecture for Internet Data
Transfer
Niraj Tolia, Michael Kaminsky, David G. Andersen,
and Swapnil Patil
Data Oriented Transfer Service
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Seperate control from data
Control logic is application specific; use DOT for
all data transfer
Benefits:
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Transfer techniques can reused and new ones tried
Coding, multi-pass compression, caching etc. can
be applied by the transfer service
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Multi-path transfers
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Cross application data processors
DOT
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DOT provides an
architecture
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API and a plugin
Transfer Plugins: eg. Multi-path, portable storage
Storage Plugins: access to local data, divide data
into chunks, compute hashes
Basic API:
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Sender calls put with data, gets back an OID
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Receiver uses OID to get data
Evaluation
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Multipath Plugin: Using two 100 Mbit/s Ethernet
links, transfer time went down from 3.59 seconds
to 1.90 seconds
Modified Postfix mail server to use DOT
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Minimal modification: 184 LoC
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DOT saves 20% of total message bytes transferred
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Duplicated messages
Partial redundancies in messages
Thank You!