SONET: No more techno-junking

We are in a world where versatility of telecommunication systems to transmit audio, data, image, and video signals over high-speed networks is imperative. The trend in optical telecommunication system is shifting increasingly towards convergence, delivery of audio, data, images, and video through diverse transmission and switching systems that supply high-speed transportation over any medium to any location.

Synchronous optical network or SONET fits the bill. Its modular, service-independent architecture offers vast capabilities in terms of service flexibility. And, what’s more, the transport infrastructure for worldwide telecommunications for at least the coming 20 to 30 years will be provided by the comprehensive SONET/synchronous digital hierarchy (SDH) standard. SONET should be a familiar acronym the world-over for the next few decades at the least.

What is SONET?

Synchronous optical network (SONET) is a standard for optical telecommunications transport. SONET provides for increased configuration flexibility and bandwidth availability, which has significant advantages over the older telecommunications system.

Get the SONET advantage

Some of the key advantages of SONET are:

• increase in network reliability



• remote provisioning provides centralized maintenance



• synchronous multiplexing format & structure ­ helps carry lower level digital signals (viz. DS­1, DS­3) that greatly simplifies the interface to digital switches, digital cross-connect switches, and add-drop multiplexers



• a flexible architecture capable of accommodating future applications, with a variety of transmission rates.

What are the benefits of SONET?

The transport network using SONET provides much more powerful networking capabilities than existing asynchronous systems. Its capabilities include:

• Grooming: It refers to either consolidating or segregating traffic to make more efficient use of the facilities



• Midspan meet with multivendor: SONET allows optical interconnection between network providers regardless of who makes the equipment



• Because of the bandwidth capacity it offers, SONET is a logical carrier for ATM–asynchronous transfer mode–a fast packet-switching technique



• Reduced cabling: As SONET system allows a multi-point or hub configuration, it reduces the need for back-to-back terminals as compared to asynchronous systems which are dominated by back-to-back terminals due to inefficient architecture.



• One connection can reach all network elements within a given architecture.

How was it before SONET?

Before SONET, the first generation of fiber-optic systems in the public telephone network used proprietary architectures, equipment, line codes, multiplexing formats, and maintenance procedures.

The users of these equipment around the world wanted standards so that they could mix and match equipment from different suppliers, thereby reducing capital costs by not having to junk the whole system.

Thus, the standard for connecting one fiber system to another was created by ECSA in 1984, and this standard is called SONET.

How does it work?

SONET defines a technology for carrying many signals of different capacities through a synchronous, flexible, optical hierarchy. This is accomplished by means of a byte-interleaved multiplexing scheme. Byte-interleaving simplifies multiplexing and offers end-to-end network management.

With fast paced technological innovation rendering several technologies obsolete in a very short time, in this scenario a proprietary technology would require total replacement and added costs. But a standard like SONET, which facilitates multi-vendor equipment mix-match, plus other numerous benefits, should definitely help the communication world from another "techno-junking" because of technology obsolescence.