Characteristics of P2P Computing
The importance of P2P computing can be better understood by looking at its
characteristics:
■■ P2P computing is decentralized and, thus, resilient by nature.
■■ Self-organization is a native property of P2P computing.
■■ P2P networks have high usability. Their operation and use require no
understanding by users and no maintenance by network operations
staff.
■■ Ad hoc networks can be set up with absolute minimal configuration.
■■ Performance is a function of the bandwidth and computing power of
the peer nodes. Performance can be optimized using:
■■ Caching
■■ Smart routing algorithms (such as in Chord)
■■ P2P networks are scalable from small home and enterprise networks to
global Internet scale.
■■ Secure P2P networks can be built and are easier to audit for possible
vulnerabilities because of limited complexity.
■■ The cost of ownership is minimal because of the lack of network infra-
structure and also because of the lack of operations costs for service
infrastructure. Later in this chapter, we will discuss the disruption this
causes to the legacy telecom and VoIP industries.Security of P2P Networks
P2P networks have two broad security aspects:- It is harder to attack P2P nodes because of the distributed nature of P2P.
Denial of Service (DOS) attacks are most often performed by concen-
trating the power of many compromised computers on one single tar-
get—this approach does not work for P2P. Secure overlay systems
(SOS) [6] can be built by using system properties, such as the mobility
of peers (harder to impersonate and to find the target) and the large
number of targets. Other techniques for secure overlays include secret
proxy servers that are known only to a small number of users. The
secret servers are actually another network overlay, called the secure
overlay access points.
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