Standards
R2 signalling refers to a vast number of variants of R2 that resemble each other to varying degrees. For most R2 variants, each such variant of R2 is promulgated by the PTT of each nation and/or by a telecommunications equipment manufacturer who addressed that national market with a nation-specific adaptation of one of their products.
The international version of R2 is an inter-nation protocol for R2 signalling that crosses national boundaries, and is neither a superset nor a subset of any national variant of R2. Conversely, each national variant of R2 is intra-nation. The international standard R2 was first promulgated by CEPT in the 1970s and then later by ITU-T with only modest evolution.
Read more about this topic: R2 Signalling
Famous quotes containing the word standards:
“In this nation I see tens of millions of its citizens, a substantial part of its whole population, who at this very moment are denied the greater part of what the very lowest standards of today call the necessities of life. I see one third of a nation ill-housed, ill-clad, ill-nourished. The test of our progress is not whether we add more to the abundance of those who have much, it is whether we provide enough for those who have too little.”
—Franklin D. Roosevelt (1882–1945)
“As long as our people quote English standards they dwarf their own proportions.”
—Ralph Waldo Emerson (1803–1882)
“A generation which has passed through the shop has absorbed standards and ambitions which are not of those of spaciousness, and cannot get away from them. Everything with them is done as though for sale, and they naturally have in view the greatest possible benefit, profit and that end of the stuff that will make the best show.”
—Alexander Herzen (1812–1870)