A sign is something other people, apart from the patient can detect, such as a swelling, rash, or change in skin color. A symptom is something only the patient feels and describes, such as a headache, fatigue, or dizziness. For the most part, the symptoms of HIV are the result of infections caused by bacteria, viruses, fungi and parasites.
Coarse wavelength-division multiplexing â cost-efficient transport in short-distance optical networks. CWDM is the technology of choice for cost-efficiently transporting large amounts of data traffic in telecom or enterprise networks. Optical networking and especially the use of CWDM technology has proven to be the most cost-efficient way of addressing this requirement.
WDM systems are divided in different wavelength patterns: conventional or coarse and dense WDM. 1  Conventional WDM systems provide up to 16 channels in the 3rd transmission window (C-band, around 1550 nm) of silica fibers.  Dense WDM (DWDM) uses the same 3rd transmission window (C-band) but with denser channel spacing. Channel plans vary, but a typical system would use 40 channels at 100 GHz spacing or 80 channels with 50 GHz spacing. Some technologies are capable of 25 GHz spacing (sometimes called ultra dense WDM).