Coarse WDM and its applications Coarse Wavelength Division Multiplexing (CWDM), a WDM technology, is characterized by wider channel spacing than Dense WDM (DWDM) as defined in ITU-T Rec. G.671. CWDM systems can realize cost-effective applications, through a combination of uncooled lasers, relaxed laser wavelength selection tolerances and wide passband filters. CWDM systems can be used […]
Data Transmission
Технология CWDM
Технология CWDM доказала свою эффективность для решения задач уплотнения оптических несущих – WDM (Wavelength Division Multiplexing). Суть этой технологии заключается в том, что потоки данных, передаваемые по отдельным оптическим линиям, с помощью СWDM устройств (CWDM мультиплексоров) cоединяется в единый оптический сигнал, передаваемый по оптоволокну. На ответной стороне выполняется демультиплексирование (обратная операция). Ключевые преимущества CWDM: До […]
Practical Considerations of DWDM Deployment
Based on bit rate alone, DWDM has a fourfold advantage even over the latest—albeit nascent—TDM option, STM–64/OC–192. To fairly compare the two technologies, however, we need to review and outline what would be an ideal technological solution for expanding network capacity. This has to be done in a broad sense, recognizing that there are instances […]
Purpose and Scope of the X2 MSA
This Multi-Source Agreement (MSA) defines X2, a compact 10 Gigabit/s optical transceiver. The MSA should be regarded as a supplement to the XENPAK MSA and does not attempt to re-specify areas already covered by XENPAK. Every attempt has been made to make this document succinct and contain only information required to make or use the […]
The differences between SDH and SONET
SDH stands for synchronous digital hierarchy. SDH is the synchronous technology used everywhere except the US, Canada and Japan. Development of this international counterpart to SONET began a few years after SONET. The differences between SONET and SDH are based primarily on the different asynchronous bit rates that must be mapped into them. In developing […]
6 reasons why SONET
With the introduction of PCM technology in the 1960s, communications networks were gradually converted to digital technology during the years that followed. To cope with the demand for ever-higher bit rates, a multiplex hierarchy or plesiochronous digital hierarchy (DSn) evolved. The bit rates start with the basic multiplex rate of 1.5 Mb/s with a further […]
7 Reasons Why SDH (Synchronous Digital Hierarchy)?
Communications networks gradually converted to digital technology after PCM was introduced in the 1960s. A multiplex hierarchy known as plesiosynchronous digital hierarchy (PDH) evolved to cope with the demand for everhigher bit rates. The bit rates start with the basic multiplex rate of 2 Mbps with further stages of 8, 34, and 140 Mbps. In […]
Multi-port 60W PoE Gigabit media converters
Omnitron Systems Technology recently introduced the OmniConverter GHPoE/S, which the company described as “the first multi-port, 60 Watts Power over Ethernet Gigabit media converter.” Omnitron explained the converter is compatible with IEEE 802.3af PoE (15 Watts) and 802.3at PoE Plus (30 Watts) standards, and “provides 100/1000-Ethernet-fiber-to-10/100/1000-copper” as a media converter. “It is classified as Power […]