Terminals in CSMA-CA group share seeds for pseudo-random back-off generation and maintain table of all group members' waiting times

摘要

Terminals in a shared medium network using carrier sense multiple access â collision avoidance (CSMA-CA) (eg an IEEE 802.11 wireless network) calculate their back-off time (eg. using a pseudo-random number/sequence generator (PRNG/PRSG)) from a specific value/seed (eg. the terminal nodeâ s ID) (steps 500-510). The terminals associate into a group by sharing the seeds with all other members, each member then creates and maintains a table with every memberâ s back-off time using the PRNG. Duplicate back-offs (ie. Potential collisions) can be stripped from the table and recalculated (555). The back-off slot counts are decremented (535-540) until transmission at a zero count (530,545-555) in the normal fashion. Grouped terminals can be mixed in a network with terminals using standard CSMA-CA, hence collisions can still occur (545).