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What is DWDM?

What is DWDM?

arioonet dwdm

Dense wavelength division multiplexing (DWDM) is an optical multiplexing technology used to increase the bandwidth of existing fiber networks. DWDM works by combining and simultaneously transmitting multiple signals at different wavelengths over a single fiber. This technology creates multiple optical channels and thus multiplies the capacity of the physical environment.

DWDM-based network structures can be divided into three classes, which are point-to-point DWDM link, DWDM wavelength routing with electronic TDM and switching/routing backbone network, and all DWDM optical networks.

1. Simple link to DWDM point

In this architecture, electronic nodes can be SONET/SDH switches, Internet routers, ATM switches, or any other type of network node. The DWDM node consists of a pair of wavelength multiplexer/de-multiplexer (wavelength optical devices) and a pair of optical-electrical/electrical-optical converters. Each wavelength channel is used to transmit a data stream separately. A DWDM wavelength multiplexer combines all wavelength channels into a single light beam and sends it down a single fiber. The combined light of multiple wavelengths is separated by a demultiplexer at the receiver end. Then the signals carried by each wavelength channel are returned to the electrical domain through the OEO converter. In this way, a single wavelength channel can be equivalent to a traditional fiber core where a single optical beam is used to carry information. It is worth noting that wavelength channels in one fiber can be used for both directions or two fibers are used for each direction.

2. Wavelength routing with electronic TDM

In this structure, wavelength routers are used to configure or reset the network topology in the optical domain, and TDM network nodes are used to perform multiplexing and switching in the electrical domain. This hybrid optical and electrical network architecture can be used in SONET/SDH where the electrical TDM network nodes are SONET switches, or in the Internet where the TDM network nodes are Internet routers. This architecture can also be used in an ATM network where the TDM network nodes are ATM switches.

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Q1: How many channels does the DWDM system have?

A1: DWDM wavelength is locked on C-band,

At 100GHz network (0.8nm) can reach up to 48 wavelengths,

In the 50GHz network (0.4nm) it can get 96 wavelengths.

Q2: What services is DWDM Mux Demux usually used for?

A2: They use this system for long distance transmission. The protocol is transparent and its applications include 10/1G Ethernet, SDH/SONET, 16/8/4/2/1G Fiber Channel, FTTx and CATV.

Q3: Can the DWDM Mux Demux be changed according to customer’s requirement?

A3: Yes, we will customize the system according to your specific needs. Any specific wavelength, any connector, any module and distance can be done.

Passive DWDM and CWDM – Which is better?

A4: For short distance (like 70km), low capacity, below 10G
. CWDM works better and more efficiently.

If you want speed protocols up to 100G / 200G per channel, for long-term applications, DWDM is better.

Q5: Does this system need to be ordered from abroad?

A5: No, it is currently produced by Eriont inside Iran.