Local telecommunication companies now have access to the Tejas Networks range of carrier grade communications infrastructure equipment through southern African distributor Comtest.
Comtest recently played host to Dr Kumar Sivarajan, the chief technology officer of Tejas Networks. Dr Kumar used his visit to South Africa to meet leading telecommunications companies such as Vodacom, MTN and Neotel, where he discussed advances in optical transport networks for packet services.
According to Dr Kumar: "The world's optical fibre transmission networks are built to the synchronous digital hierarchy (SDH) and synchronous optical network (SONET) standards. The first generation of SDH/SONET was developed in the 1990s and quickly became the mainstay of optical transport in service provider networks all over the world due to its high reliability and detailed fault isolation capabilities."
However, this generation of SDH was designed mainly to cater to voice traffic that was predominant at that time. Dr Kumar continues: "The next generation of SDH systems was standardised in 2002-2003 and focused on efficient transport of data/Ethernet services over first- and second-generation SDH/SONET networks, using techniques such as virtual concatenation (VCAT), generic framing procedure (GFP) and link capacity adjustment scheme (LCAS). These standards ensured that the investments made by service providers in their SDH infrastructures were fully protected."
Today, most service providers need to provide other data services including Ethernet LAN (ELAN) and also support triple-play networks with IPTV. Supporting separate networks for data and voice/TDM services is a costly proposition both in terms of capital expenditure and operational expenses. Hence, most service providers will deploy a converged transport network that is capable of supporting all applications including switched data services (IPTV, ELAN, MPLS), Ethernet and other private lines, Internet access including aggregation of DSLAM traffic, as well as transport of E1s/T1s for wireless backhaul and legacy traffic. Such a transport network can be built using SDH/SONET or by using a pure-packet-switched (Ethernet or MPLS) network. The main weaknesses of the latter Ethernet-switching based approach have historically been rapid fault-restoration and operations, administration and maintenance (OAM) capabilities. Recent technologies and standards that address these issues include the emerging Ethernet OAM standards, Provider Backbone Transport (PBT) and Transport-MPLS (T-MPLS).
For more information contact Richard Lewis, Comtest, +27 (0)11 254 2200, [email protected], www.comtest.co.za
| Tel: | +27 10 595 1821 |
| Email: | [email protected] |
| www: | www.comtest.co.za |
| Articles: | More information and articles about Comtest |
© Technews Publishing (Pty) Ltd | All Rights Reserved
printer friendly version