Single fibre transceivers

[nicholab]

Can you get Single fibre transceivers for popular modes of switch yet? I was looking at the ADVA box and it only use one fibre can we do the same? It could be a cost effective way of getting more links then again it could cost silly money for the transceivers.

[ellsandell]

You can get SM transceivers for all types of switches, they are more expensive optics generally but if you are installing new fibre runs always single mode over multi mode. (You can get some fairly cheap non branded SM transceivers)

[Ric_]

@nicholab If I understand your question correctly, you are effectively trying to get twice as many runs by using SM rather than MM fiber. If this is the case, it is worth baring in mind that the actual fiber characteristics are not the same so your fiber may not be suitable for SM transmission.

 

Unless you have runs requiring SM (which is unlikely) I would personally just run more cores at once. I'm not a fan of random brands for transceivers and prefer to match the brand of transceiver to the device to make sure that your warranty/support is not affected in any way (i.e. the first thing that the manufacturer will tell you is to remove all non-approved modules before troubleshooting an issue).

[AlanD]

I think there may some confusion here. I think the original question is about using a SINGLE fibre (rather than a pair) for a duplex connection. I don't think its about Single Mode and Multimode fibre which is do with scattering of light and multipath reflections over longer distances. I've never heard of creating a duplex connection over a single fibre - but it doesn't surprise me to hear that it might be possible. I assume that there are specialist fibre modules to do this - although I suspect range is reduced because there will be "noise" scattered back. Maybe it would get you a working duplex connection if one fibre failed...but suspect that in most cases the cost of two such modules would be a lot more than dragging in a new fibre run and terminating it.

[m25man]

I've never heard of creating a duplex connection over a single fibre

 

BIDI Fibre modules are well supported in many switches,

See the HP compatibility matrix

http://h20565.www2.hpe.com/hpsc/doc/public/display?docId=c05115518&mkt_tok=eyJpIjoiTXpRd1pETXpNakF3Wm1ReCIsInQiOiJ4NStTc0lEU3BHa3duQVA5dkY2dkprRUlTeGZlVnJwMkpWYWlFMW5yVjFXc0NzT2xBUmVQbHJpdXVEOVBiaU84UVwvUmIxd3FXQ1lsVHg5bHUxS1oyaXhkS0NVdkV4WFcwdjdQNUlUNVdLNm89In0%3D#page27

 

Generally Single Mode Fibre using WDM (wavelength division multiplexing) with the TX and RX using different colours of light spectrum in a bi-directional transceiver using a single fibre.

 

You will often see them used in ISP CPE equipment to share a fibre between multiple subscribers.

 

A bit like using VLAN tags on an Ethernet connection, one data stream uses the red/blue wavelength whilst another uses yellow/orange.

Thus two connections can use the same fibre at the same time

 

BiDi and WDM/DWDM/CDWDM are all encompassed in the SFP/SFP+ specification.

 

The transceivers are readily available however the hardware that can make use of them is pretty specific and your campus fibre has to support it.

 

Cisco CPE and Routers commonly use them and most Tier1 vendors have switch support for them.

They have been common in video transmission over fibre for years.

 

You won't see them widely supported in current budget switch vendors hardware.

You get what you pay for in the networking game.

 

Most schools have fibre installed for a specific requirement I don't know of many that had WDM in mind when they signed to order...

 

If you've never heard of WDM it's about as significant to networks as DVBT2 was to televisions.

[Mark-wilde]

A single fiber for the QVDA box can't do the same as optical transceivers connecting with fiber patch cables on either ends.

 

FYI, compatible modules are usually much cheaper than the original ones.

[RichardZh]

How about the Ethernet media converter？