Automatic Repeat ReQuest(ARQ) When the receiver detects errors in a packet, how does it let the transmitter know to re-send the corresponding packet? Systems which automatically request the retransmission of missing packets or packets with errors are called ARQ systems Three common schemes Stop Wait
Programming Languages · Control Conditionals Functions function calls Threads Data Scalars: booleans, numbers, strings Records/ structures Classes, types sept.8.2003
Satellite communications Architecture Identify Requirements Specify architectures Determine link data rates Design Size each link Document your rationale
Overview Spacecraft data processing requires microcomputers and interfaces that are functionally similar to desktop systems However, space systems require: - Low power, volume, and mass High reliability and fault tolerance
Slide 12.1.1 In the last lecture, we introduced mutation as a component of 6001s|cP our data structures We saw for example that set was a Environment mode way of changing the value associated with a variable in our system, and we saw that set-car! and set-cdr! were ways of changing the values of parts of list structure Now, several important things happened when we introduced
6.001 Structure and Interpretation of Computer Programs. Copyright o 2004 by Massachusetts Institute of Technology 6.001 Notes: Section 10.1 Slide 1o.1.1 Table: a set of bindings Over the past few lectures, we have introduced the concepts of data abstractions, types and aggregate structures. In this lecture
