J-carrier (Japanese-carrier)

A hierarchy of standards for digital transmission that essentially is the

Japanese version of the United States T-carrier digital carrier system.At levels one and two, J-carrier mimics T-carrier with respect to the signaling rates, but diverges at level three and beyond. J-carrier also uses a different PCM companding technique (A-law rather than µ-law). As J-carrier is medium-independent, it can be provisioned over any of the transmission media, at least at the J-1 rate of 1.544 Mbps. (At the J-3

rate of 32.064 Mbps, twisted pair is unsuitable due to issues of signal attenuation.) The fundamental building block of J-carrier is a 64-kbps channel, referred to as DS-0 (Digital Signal level Zero).Through time division multiplexing (TDM), J-carrier interleaves DS-0 channels at various signaling rates to create the services that comprise the Japanese digital hierarchy, as detailed in Table J-1.

• PON (Passive Optical Network)
• PON (Passive Optical Network)
• PON (Passive Optical Network)
• Pony Express
• POP
• POP3 (Post Office Protocol version 3)
• port
• portability
• Portable Network Graphics (PNG)
• portal
• portal
• portmanteau
• portmanteau
• POS
• positive
• positive intrinsic negative (PIN)
• Postel, Jon (1943–1998)
• Postel’s Law
• Post Office Code Standardization Advisory Group (POCSAG)
• Post Office Protocol (POP)
• Post, Telegraph, and Telephone (PTT)
• potential
• POT (Point Of Termination)
• POTS (Plain Old Telephone Service)
• pound sign