Transcript 1 - IETF

ICN Considerations for ISP’s
Existing Networks
Lichun Li, Xin Xu, Jun Wang, Zhenwu Hao
[email protected]
{xu.xin18, wang.jun17, hao.zhenwu}@zte.com.cn
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Deployment Considerations:
ICN over layer-2 or layer-3?
• ICN scenarios: Internet, ad hoc networks, DC, etc
• ISP’s existing networks: ICN overlay over IP network
– Incremental deployment allowed
– No need to deploy content routers in the places where link cost is low and QoS is
satisfied.
– Fewer content router tiers: lower CAPEX and OPEX
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Deployment Considerations:
Benefits of cache at network edge
• earlier cache hit means better QoS and less link cost
• reducing the load of core content routers
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Deployment Considerations: benefit of cache in core
On the Scale and Performance of Cooperative Web
networks
Proxy, SOSP 99
cumulative distribution of views
1
0.8
0.6
ifeng UGC
PPTV movie
Sohu movie
Tudou movie
Tudou TV
Tudou UGC
0.6~2%
UGC
6~20%
TV/movie
0.4
0.2
Cache hit rate increases
20-25%
0
-4
-3
-2
-1
10
10
10
10
normalized rank of videos (ranked by one-day view count)
•
high cache hit rate requires both large
cache size and large user number
– Only possible in the core network
– DPI cache size today: 100s TB
0
10
Cache size increases
more than 100 times
Web caching and Zipf-like distributions:
Evidence and implications, Infocom 99.
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Routing and Caching Control
• Decentralized
– Routing table populating: Content routers run routing
protocols and routing algorithms
– Cache replacement: content routers run replacement
algorithm, e.g. LRU
• Centralized
– Routing table populating: controller(s) collect topology
data, generate routing tables and send routes to routers
– Routing and Caching policies: controller(s) send policies
to routers
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Routing and caching policies
• To meet QoS requirement
– an ISP may decide routing path and cache priority
considering factors like content type, content popularity
and the distance to the content source.
• To reduce link cost
– an ISP may assign more cache resources for the contents
passing through costly links by controlling routing path
and/or cache priority
• To balance link load and cache load
• To provide better services
– For paid users or paid content providers
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Example of ICN inside ISP
Centralized ICN controller
Routing control
Caching policy control
Content
source
ICN
controller
Content router at
core network
ICN over IP
Content router at
network edge
IP router
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Thank you!
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