The Evolution of XTP

The design of XTP has been a 3 year process so far with roots traceable to work in the 1970's and 80's. There have been roughly ten distinct revisions of the protocol. Since Revision 3.4 in June 1989 there has been an effort to stabilize the design. This has been accomplished. The most recent versions - Revision 3.4 and 3.5 - were about 14 months apart whereas earlier versions were 3 to 6 months apart. Fortunately the net effect of the change from Revision 3.4 to 3.5 was to remove mechanism from the design. There have been at least nine distinct software implementations of the protocol. Experience with these implementations has been fed back into the protocol specification. We believe that the functionality in the present design, Revision 3.5 plus Addendum 1a, is strengthened by the number of alternative mechanisms that have been tried and rejected. XTP history and evolution will be reviewed in this paper with a focus on some of the protocol mechanisms that have changed over time. Int..

XTP/PE Design Considerations

The Xpress Transfer Protocol, XTP, is an approach to protocol design for next generation networks. The Protocol Engine, PE, is a hardware architecture for implementing network protocols and system interfaces using VLSI techniques. The two projects are related: XTP is designed with a PE in mind. This paper presents some of the ideas and goals in XTP. Introduction XTP [1] represents a compromise between issues of bandwidth, latency, protocol complexity, VLSI constraints, transport services, system interfacing, and speculation about future network evolution. The general goals are to demonstrate feasibility of Gbit/sec operation, to fit in a VLSI environment, and to provide adequate functionality for distributed system applications. Bandwidth Network interfaces can be based on software plus specialized hardware for the link level functions, and can be effective at the 10 Mbit/sec level. As network bandwidths from 100 Mbit/sec to 2 Gbit/sec become available it is necessary to apply hard..

Stereotactic ablative radiotherapy versus standard radiotherapy in stage 1 non-small-cell lung cancer (TROG 09.02 CHISEL): a phase 3, open-label, randomised controlled trial

Background: Stereotactic ablative body radiotherapy (SABR) is widely used to treat inoperable stage 1 non-small-cell lung cancer (NSCLC), despite the absence of prospective evidence that this type of treatment improves local control or prolongs overall survival compared with standard radiotherapy. We aimed to compare the two treatment techniques. Methods: We did this multicentre, phase 3, randomised, controlled trial in 11 hospitals in Australia and three hospitals in New Zealand. Patients were eligible if they were aged 18 years or older, had biopsy-confirmed stage 1 (T1–T2aN0M0) NSCLC diagnosed on the basis of F-fluorodeoxyglucose PET, and were medically inoperable or had refused surgery. Patients had to have an Eastern Cooperative Oncology Group performance status of 0 or 1, and the tumour had to be peripherally located. Patients were randomly assigned after stratification for T stage and operability in a 2:1 ratio to SABR (54 Gy in three 18 Gy fractions, or 48 Gy in four 12 Gy fractions if the tumour wa