For distributed systems and networks, we often should assume that there are adversaries
Everywhere in the network
Adversary may: eavesdrop, manipulate, inject, alter, duplicate, reroute, etc…
Adversary may control a large number of network nodes that are geographically separated
Dolev-Yao Threat Model:
A very powerful adversarial model that is widely accepted as the standard by which cryptographic protocols should be evaluated
Eve, the adversary, can:
Obtain any message passing through the network
Act as a legitimate user of the network (i.e.
Nothing is more frustrating than knowing you have previously solved a complex
problem but not being able to find the document or note that specified the
solution. It is not uncommon to refuse to rework the solution because you
know you already solved the problem and don’t want to waste time redoing
past work. In fact, taken to the extreme, you may waste more time finding the
previous solution than it would take to redo the work. This is a direct result of
our information management facilities not keeping pace with the capacity of
our information storage....
Smart homes are intelligent environments that interact dynamically and respond readily in an adaptive manner to the needs of the occupants and changes in the ambient conditions. The realization of systems that support the smart homes concept requires integration of technologies from different fields. Among the challenges that the designers face is to make all the components of the system interact in a seamless, reliable and secure manner.
To solve the problems caused by the merger, no schema changes are required.
Merge the customer entity sets removing duplicate tuples with the same social-
security ﬁeld. Before merging the branch entity sets, prepend the old bank name
to the branch-name attributeineachtuple.The employee entity sets can bemerged
directly, and so can the payment entity sets. No duplicate removal should be
performed. Before merging the loan and account entity sets, whenever there is a
number common in both the banks, the old number is replaced by a new unique
number, in one of the banks....
The forward process makes use of the information contained in the
hypothesis A. The backward process tries to find a chain of statements leading
to the fact that the conclusion B is true.
With the backward process, you start with the statement B that you are
trying to conclude is true. By asking and answering key questions, you derive
a sequence of new statements with the property that if the sequence of new
statements is true, then B is true. The backward process continues until you
obtain the statement A or until you can no longer ask and/or answer the key
One ongoing issue in translational informatics is patient privacy and the security of
data. An approach that has been pursued using semantic technologies is to encode
data access rules and then check all data accesses against these policies . For exam-
ple,apolicycangiveahospitalbillingspecialist access to data about procedures per-
formed at the hospital for the purpose of insurance billing. Then, when procedure data
is requested, the requester would need to show that they were a billing specialist and
provide the purpose for which they want to access the data.