Crowdly

Make resources accessible

Resolve scaling problems

Achieve high degree of transparency

Distributed systems differ from traditional software because:

There is a latency problem

Components are dispersed across a network

OS are controlled by management application

Performance degradation is one form of:

Openness problem

Scalability problem

Migration problem

What does it mean by Degree of Transparency:

That is how many layers of system is used to achieve distributed transparency

Percent of machines, in distribute system, that are transparent for users

That is not aiming only for transparency but also considering performance and comprehensibility

Connectivity layer consists of:

Mechanisms of resource management

Applications that operate within a virtual organization

Communication protocols for supporting transactions

Interfaces to local resources

Cluster Computing Systems build with:

Object- based architecture

Mixed architecture

Client-server architecture

Nested transactions contain:

Subtransactions

Reference to databases

Queues

Distributed pervasive systems are:

Often small, battery-powered, mobile, and only wireless

Use management application

Distributed across part of territory

Transaction processing monitor is:

Communication protocol

Fabric layer

Kind of middleware

What are four characteristic properties of Transaction?

Transactions interfere among them

Transaction happens indivisibly

Transaction does not violate system invariants

Transaction makes temporary changes

Transactions do not intervene with each other

Transactions are inconsistent

Once a transaction commits, the changes are permanent