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The space communication environment and mobile and wireless communication environments show many similarities when observed from the perspective of a transport protocol. Both types of environments exhibit loss caused by data conuption and link outage, in addition to congestion-related loss. The constraints imposed by the two environments are also similar -power, weight, and physical volume of equipment are scarce resources. Finally, it is not uncommon for communication channel data rates to be severely limited and highly asymmetric. We are working on solutions to these types of problems for space communication environments, and we believe that these solutions may be applicable to the mobile and wireless community. As part of our work, we have defined and implemented the Space Communications Protocol StandardsTransport Protocol (SCPS-TP), a set of extensions to TCP that address the problems that we have identified. The results of our performance tests, both in the laboratory and on actual satellites, indicate that the SCPS-TP extensions yield significant improvements in throughput over unmodified TCP on errorprone links. Additionally, the SCPS modifications significantly improve performance over links with highly asymmetric data rates.

Growing concern with the panpsychist's ostensive inability to solve the 'combination problem' has led some authors to adopt a view titled 'Cosmopsychism'. This position turns panpsychism on its head: rather than many tiny atomic minds, there is instead one cosmos-sized mind. It is supposed that this view voids the combination problem, however I argue that it does not. I argue that there is a 'de-combination problem' facing the cosmopsychist, which is equivalent to the combination problem as they are both concerned with subjects being proper parts of other subjects. I then propose two methods for both theorists to avoid the problem of subjectsubject proper parthood relations: a distinction between absolute and relative phenomenal unity, and a modification of the essential nature of subjects. Of these two options, I find the latter option wanting and propose that the first should be adopted.

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Analytical models for unidirectional-bus protocols often employ a Bernoulli process to approximate the occupancy process of the slots on the bus. This approximation, which assumes independence among the statuses of consecutive slots on the bus facilitates analysis; however, it is known to provide inaccurate results, especially for stations located at the downstream end of the bus. In this paper, we quantify this inaccuracy by comparing results from the Bernoulli-based analytical model with results from a simulation model of two different access protocols. We study the Bernoulli-based model as compared to simulation in its ability both to predict network delay behavior and to describe the actual slot occupancy process as characterized by various statistical characteristics. We reveal the inaccuracy of the model as a function of station index and network load, and we identify a characteristic of the slot occupancy pattern not captured by the Bernoulli-based model, that is crucial to more accurately modeling the process for the sake of delay analysis.