DSL Advances

10.3. The Basis Systems

The basis systems are loop transmission systems deployed in the network that provide the basis for establishing spectral compatibility criteria for within a loop cable. Selection of the basis systems list required industry consensus in order to be adopted in the spectrum management standard.

The basis systems list per the first issue of the spectrum management standard T1.417 are as follows:

1. Voice grade services, which include analog voice service, network signaling, data (e.g., via voice-band modem) and tones that utilize the frequency from 0 to approximately 4 kHz.

2. Digital data service (DDS) based on signals defined in T1.410-1992. These signals use alternate mark inversion at a maximum line rate of 72 kb/s. The services ...