he ubiquity of broadband Internet is at the origin of
the emergence of Over-The-Top (OTT) subscription
services such as Netflix or Hulu. The specificity of
OTTs is to provide broadband video and audio deliv-
ery to Internet users without a particular dedicated involve-
ment of their Internet Service Provider (ISP). To offer high
quality multimedia content distribution, OTTs commonly rely
on distribution infrastructures with multiple points of pres-
ence connected at main Internet exchange points. This need
for advanced distribution infrastructures derives from the cur-
rent technical limitations of TCP/IP that bind communications
to the location of the server by using IP addresses. Moreover,
the multimedia nature of OTT services requires low latency,
jitter, and loss rate. Hence, OTT servers should not be in
topologically and performance constrained locations, as it usu-
ally happens in P2P networks, and should limit the number of
relay hops as much as possible. OTTs could simplify their dis-
tribution infrastructure by following an Information-Centric
Networking (ICN) [1] approach. ICN relies on the “routing by
name” paradigm and leverages in-network caching where
intermediate network nodes can cache any piece of data pass-
ing through them. This caching capability of ICN networks
ensures that popular content is cached on routers close to the
clients [2].
As a matter of fact, ICN can significantly increase content
distribution efficiency with respect to legacy technology [1,2].
When capital expenditures are not insurmountable obstacles
to deploy ICN-capable network elements, the advantage for
ISPs to deploy ICN inside their networks is immediate as ICN
inherently helps in reducing overall link usage. The advantage
is less straightforward for OTTs as they are very sensitive to
network conditions of networks they do not control. A reason-
able way for OTTs to profit from ICN is to construct an ICN
overlay that interconnects OTT servers and clients. The ratio-
nal behind using overlays is that they can be incrementally
deployed in the Internet and hence do not require network
nodes from the underlay (i.e. ISP’s equipment) to explicitly
participate in the ICN network. In the ICN overlay, every
node implements the same ICN protocol, and OTT clients
caching contents can deliver them to other clients on behalf of
the OTT provider. The routing system determines from which
node customers retrieve the content (either a caching node or
directly from a server).
Figure 1 synthetizes the simplest interaction between the
stakeholders (OTT, caching customer nodes, non-caching cus-
tomer nodes) for the baseline case of three ICN nodes beyond
which two are hosted by OTT consumers (nodes II and I in
the figure) and one is hosted by an OTT provider server
(node OTT in the figure). The routing system allows a cus-
tomer node to retrieve the content either directly from the
OTT server node or from the other customer node. In the fig-
ure, arrows indicate the direction of requests to obtain con-
tent and the label specifies the strategy adopted by the node
performing the request. Customer I (resp. II) has the choice
between four strategies: it can retrieve the content from the
OTT server, caching it for customer II (resp. I) (label =
OTT
c
); it can retrieve it from the OTT server, not caching it
(label = OTT); it can retrieve it from the other customer,
caching it (label = II
c
(resp. I
c
)); or it can retrieve it from the
other customer, not caching it (label = II (resp. I)). For the
sake of simplification we do not show impossible strategy
combinations.
In our study, we adopt the standpoint of the OTT provider
willing to incent the usage of the ICN overlay among its cus-
tomers, under the assumption that using the ICN overlay is
always profitable for the OTT provider: when customers
retrieve content from the OTT server it is equivalent to not
using the overlay; and the OTT infrastructure load is reduced
when customers retrieve content from other customers. In
our study, we also assume that customers are independent
and selfish, i.e. not prone to binding cooperation in ICN
provisioning. In this context we show that with the right
incentives the OTT provider can make their customers coor-
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20 IEEE Network • May/June 2014
With the explosion of broadband Over-The-Top (OTT) services, the Internet is
autonomously migrating toward overlay and incrementally deployable content dis-
tribution infrastructures. Information-Centric Networking (ICN) technologies are the
natural candidates to efficiently distribute popular content to users. However, the
strategic incentives in exploiting ICN, for both users and ISPs, are much less under-
stood to date. In this article we highlight strategic incentives for ICN overlay adop-
tion in OTT services, that is, we discus how OTTs shall shape their prices to
motivate ICN overlay usages.
On the Incentives and
Incremental Deployments of
ICN Technologies for OTT Services
Damien Saucez, Stefano Secci, and Chadi Barakat
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0890-8044/14/$25.00 © 2014 IEEE
Damien Saucez and Chadi Barakat are with INRIA Sophia Antipolis.
Stefano Secci is with UPMC.