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Reasoning Vs Inference

Inference: Inference is a general term representing the derivation of new knowledge from existing knowledge and axioms (i.e., rules of derivation) within a single step, and can be one of many kinds, such as, induction, deduction and abduction. For example, "modus tollens" is a rule of inference. Thus, one inference is the derivation of new knowledge using a single step using modus tollens. Inference is about taking in data and trying to draw a conclusion based on the limited information you have in a situation where not all the data is given. Reasoning: Reasoning is in context of a goal (e.g., decide whether a propositional formula is satisfiable or not)  and is carried out via a search process involving multiple inferences. Choices during such search have to be made such as which axiom to "fire" along with which knowledge in order to derive new knowledge. Resolution is a particular kind of reasoning involving the "resolution rule". Reasoning is

Principles of Congestion Control

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In this section, we consider the problem of congestion control in a general context, seeking to understand why congestion is a "bad thing,"   how network congestion is manifested in the performance received by upper-layer applications, and various approaches that can be taken to avoid, or react to, network congestion. This more general study of congestion control is appropriate since, as with reliable data transfer, it is high on the "top-10" list of fundamentally important problems in networking. The Causes and the "Costs" of Congestion: Congestion control can be studied by examining three increasingly complex scenarios in which congestion occurs.  In each case, we'll look at why congestion occurs in the first place, and the  "cost" of congestion (in terms of  resources not fully utilized and poor performance received by the end systems). Scenario 1: Two senders, a router with infinite buffers We begin by considering perhaps the s