icn considerations for isp’s existing networks lichun li, xin xu, jun wang, zhenwu hao...
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ICN Considerations for ISP’s Existing Networks
Lichun Li, Xin Xu, Jun Wang, Zhenwu [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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10-4
10-3
10-2
10-1
100
0
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normalized rank of videos (ranked by one-day view count)
cum
ulat
ive
dist
ribut
ion
of v
iew
s
ifeng UGCPPTV movie
Sohu movie
Tudou movie
Tudou TVTudou UGC
Deployment Considerations: benefit of cache in core networks
• 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
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On the Scale and Performance of Cooperative Web Proxy, SOSP 99
Cache size increases more than 100 times
Cache hit rate increases 20-25%
Web caching and Zipf-like distributions: Evidence and implications, Infocom 99.
0.6~2%UGC TV/movie
6~20%
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
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Content router at network edge
ICN controller
Content source
Content router at core network
Centralized ICN controller Routing control
Caching policy control
ICN over IP
IP router
Thank you!
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