03-07-2012, 04:53 PM
A Peer-to-Peer Overlay Architecture for Ubiquitous Communications and Networking
[attachment=26582]
ABSTRACT
Approaches to building an intelligent consumerfriendly
network have evolved over time from
centralized switch-based to router- and serverbased
Internet architectures. We propose to
drive this evolution further with a new highly
scalable architecture that provides features to
users derived from the computational and networking
capabilities of very large populations of
sophisticated terminals.
INTRODUCTION
How to build an intelligent, consumer-friendly
network? For over three decades, we have seen
new developments in the thinking (and the corresponding
technology) on how to build an intelligent
network that supports a wide variety of
consumer-oriented telecommunications and networking
applications. Traditional network architectures
were characterized by the embedding of
intelligence into large network elements, such as
switches, the use of relatively dumb terminals to
deliver applications to the end user, and service
creation paradigms that relied on network operators
wrestling with the intricacies of service creation.
Later, coincident with the rise of the
Internet, we saw architectures that relied on
intelligence that was split between network
routers/server farms and more sophisticated terminals
such as PCs and mobile phones running
browsers and software clients.
OVERLAYS, THEIR MANAGEMENT,
AND SECURITY
WHAT IS AN OVERLAY?
An overlay (Fig. 1) is an application layer — virtual
or logical — network that provides connectivity,
routing, and messaging between endpoints that
are addressable. Each peer in an overlay maintains
a list of neighbors and a routing table to
reach other parts of the overlay. This is often done
through the use of a distributed hash table (DHT),
although other mechanisms are possible. The
overlay protocol has operations for bootstrap, peer
join/leave, and routing table update. There is endto-
end addressing connectivity between all peers,
and automated Network Address Translation
(NAT) traversal is used to reach peers behind
middleboxes. Peers may perform specialized roles
such as super nodes, relays, and gateways. Basic
deployment models include overlays embedded in
a P2P application, overlays that are offered as a
service for other P2P applications to use, and
overlays with infrastructure level support.
HETEROGENEITY AND ADAPTIVITY
In view of a wide range of possible devices
requiring communications functionality, it is safe
to assume that they are highly heterogeneous.
Unlike most structured overlays, variable-hop
overlays [3] can support heterogeneity among
the peer population as well as changing conditions
at each peer. In the variable-hop approach,
routing table accuracy varies according to bandwidth
available at each peer for routing table
maintenance. A peer might have high bandwidth
capacity in one interval of time and low bandwidth
in another. Since a variable-hop overlay is
adaptive, peers of different bandwidth capacities
can coexist.
WIRELESS DEVICES IN
UP2P NETWORKS
Due to increased consumer demand for untethered
communication services, wireless interfaces
are being installed on a large number of consumer
devices. While most application scenarios
using such wireless devices depend on infrastructure
support for connectivity, a wide range
of novel applications (games, social face-to-face
interactions, in-meeting collaboration, etc.) are
being developed based on ad hoc communication
between these wireless devices. We envision
future scenarios where wireless devices will communicate
in an ad hoc manner while infrastructure
support is not available and take
advantage of infrastructure connectivity when
available to at least one of the ad hoc nodes. It
is important for applications on these devices
that the DHT operate seamlessly across these
networks.
CONCLUSIONS
We have devised a UP2P networking architecture
and have illustrated how a UP2P network
can be implemented by means of client software
embedded in terminal devices. This UP2P network
depends on the devices for its intelligence,
and can provide the high-quality services expected
from a user-oriented network. These networks
can be self-organizing and self-managed
or deployed and managed by an overlay network
operator. UP2P networks can adapt to heterogeneity
in terminal devices, and provide support
for wireless devices connected in both ad hoc
and infrastructure modes. If required, multiple
such networks can interoperate using a federated
architecture.
[attachment=26582]
ABSTRACT
Approaches to building an intelligent consumerfriendly
network have evolved over time from
centralized switch-based to router- and serverbased
Internet architectures. We propose to
drive this evolution further with a new highly
scalable architecture that provides features to
users derived from the computational and networking
capabilities of very large populations of
sophisticated terminals.
INTRODUCTION
How to build an intelligent, consumer-friendly
network? For over three decades, we have seen
new developments in the thinking (and the corresponding
technology) on how to build an intelligent
network that supports a wide variety of
consumer-oriented telecommunications and networking
applications. Traditional network architectures
were characterized by the embedding of
intelligence into large network elements, such as
switches, the use of relatively dumb terminals to
deliver applications to the end user, and service
creation paradigms that relied on network operators
wrestling with the intricacies of service creation.
Later, coincident with the rise of the
Internet, we saw architectures that relied on
intelligence that was split between network
routers/server farms and more sophisticated terminals
such as PCs and mobile phones running
browsers and software clients.
OVERLAYS, THEIR MANAGEMENT,
AND SECURITY
WHAT IS AN OVERLAY?
An overlay (Fig. 1) is an application layer — virtual
or logical — network that provides connectivity,
routing, and messaging between endpoints that
are addressable. Each peer in an overlay maintains
a list of neighbors and a routing table to
reach other parts of the overlay. This is often done
through the use of a distributed hash table (DHT),
although other mechanisms are possible. The
overlay protocol has operations for bootstrap, peer
join/leave, and routing table update. There is endto-
end addressing connectivity between all peers,
and automated Network Address Translation
(NAT) traversal is used to reach peers behind
middleboxes. Peers may perform specialized roles
such as super nodes, relays, and gateways. Basic
deployment models include overlays embedded in
a P2P application, overlays that are offered as a
service for other P2P applications to use, and
overlays with infrastructure level support.
HETEROGENEITY AND ADAPTIVITY
In view of a wide range of possible devices
requiring communications functionality, it is safe
to assume that they are highly heterogeneous.
Unlike most structured overlays, variable-hop
overlays [3] can support heterogeneity among
the peer population as well as changing conditions
at each peer. In the variable-hop approach,
routing table accuracy varies according to bandwidth
available at each peer for routing table
maintenance. A peer might have high bandwidth
capacity in one interval of time and low bandwidth
in another. Since a variable-hop overlay is
adaptive, peers of different bandwidth capacities
can coexist.
WIRELESS DEVICES IN
UP2P NETWORKS
Due to increased consumer demand for untethered
communication services, wireless interfaces
are being installed on a large number of consumer
devices. While most application scenarios
using such wireless devices depend on infrastructure
support for connectivity, a wide range
of novel applications (games, social face-to-face
interactions, in-meeting collaboration, etc.) are
being developed based on ad hoc communication
between these wireless devices. We envision
future scenarios where wireless devices will communicate
in an ad hoc manner while infrastructure
support is not available and take
advantage of infrastructure connectivity when
available to at least one of the ad hoc nodes. It
is important for applications on these devices
that the DHT operate seamlessly across these
networks.
CONCLUSIONS
We have devised a UP2P networking architecture
and have illustrated how a UP2P network
can be implemented by means of client software
embedded in terminal devices. This UP2P network
depends on the devices for its intelligence,
and can provide the high-quality services expected
from a user-oriented network. These networks
can be self-organizing and self-managed
or deployed and managed by an overlay network
operator. UP2P networks can adapt to heterogeneity
in terminal devices, and provide support
for wireless devices connected in both ad hoc
and infrastructure modes. If required, multiple
such networks can interoperate using a federated
architecture.