RFC 3255 (rfc3255) - Page 3 of 8

Extending Point-to-Point Protocol (PPP) over Synchronous Optical NETwork/Synchronous Digital Hierarchy (SONET/SDH) with virtual concatenation, high order and low order payloads

RFC 3255              Extending PPP over SONET/SDH            April 2002


         ANSI                   ETSI
      -----------------------------------------------------
        STS-3c (150Mbit/s)     STM-1 (150Mbit/s)
        STS-12c (620Mbit/s)    STM-4 AU-4-4c (620Mbit/s)
        STS-48c (2.4Gbit/s)    STM-16 AU-4-16c (2.4Gbit/s)
        STS-192c (9.6Gbit/s)   STM-64 AU-4-64c (9.6Gbit/s)

   Note that AU-4-4c and AU-4-16c are not generally available in SDH
   networks at present.

   With virtual concatenation the following additional WAN bandwidth
   links would be available for PPP over SONET/SDH:

        SONET

      VT-1.5-nv (n=1-64)       1.6Mbit/s-102Mbit/s
      STS-1-nv  (n=1-64)       49Mbit/s-3.1Gbit/s
      STS-3c-nv (n=1-64)       150Mbit/s-10Gbit/s

        SDH

      VC-12-nv (n=1-64)        2.2Mbit/s-139Mbit/s
      VC-3-nv  (n=1-64)        49Mbit/s-3.1Gbit/s
      VC-4-nv  (n=1-64)        150Mbit/s-10Gbit/s

   Higher levels of virtual concatenation are possible, but not
   necessarily useful.  Lower levels of virtual concatenation are
   defined in the telecommunications standards for use if needed.

   Table 1 and Table 2, respectively depict the SONET/SDH transport
   structures that are currently available to carry various popular bit
   rates.  Each table contains three columns.  The first column shows
   the bit rates of the service to be transported.

   The next column contains two values:

   a) the logical signals that are currently available to provide such
   transport and, b) in parenthesis, the percent efficiency of the given
   transport signal without the use of virtual concatenation.

   Likewise, the final column also contains two values:

   a) the logical signals that are currently available to provide such
   transport and, b) in parenthesis, the percent efficiency of the given
   transport signal with the use of virtual concatenation.






Jones & Murton              Standards Track