Configuring a Multichannel STM-1 on a Cisco router

When you have numerous E1 customers (> 8), you could terminate them on dedicated E1 ports of a router, e.g. with one or more  PA-MC-8E1/120 (EoL since 2003).
A more efficient way is to terminate them on a STM-1 port-adapter (e.g. a PA-MC-STM1), where you can aggregate up to 63 customers with one single fiber connection to the transport [...]

SDH multiplex structure

 Synchronous Digital Hierarchy (SDH) is a CCITT standard for a hierarchy of optical transmission rates. Synchronous Optical Network (SONET) is an ANSI (American National Standards Institute) standard for North America, that is largely equivalent to SDH.
Both are widely spread technologies for very high speed transmission of voice and data signals across the numerous world-wide fiber-optic networks.
SDH and SONET are [...]