There are some excellent tutorials on this topic. Fiberstore has a very nice collection of them...
http://www.fs.com/wdm-networking-cid-9.html Start with the tutorial on basics first and then build on it with others. http://www.fs.com/do-you-know-all-these-terminologies-of-wdm-technology-aid-474.html Here is another nice set of tutorials, clearly written.. http://www.fiber-optic-tutorial.com/category/network-solutions/wdm-optical-network/cwdm-dwdm-mux-demux ** The only difference conversationally between an "Active" vs "Passive" CWDM/DWDM gear is as to who is doing the 'Standard Color' to "CWDM/DWDM" optical conversions. This is what consumes/requires external power. (aka, media converter packaging) if you take a media converter and a passive mux/demux put it into one box, that now becomes an active solution if you take the media converter out, as a separate box, then the mux/demux is considered to be a passive solution. If the gear on both sides is under your control, then you can skip the media converters and just put in the matching colored optics in your gear on both sides Otherwise you deploy a media converter to convert between the colored optics to standard optics... both in context of Ethernet as well as TDM). In regards to distance and ring topology......there is no issue, just how you design the fiber path... aka fiber light link budget and optic's receive sensitivity.. just like RSSI on a Fixed Wireless link.. There are standard figures you can use for link loss, each panel appox 1 to 1.5db, (e.g. if the TX is 1-4dbm, and Rx sensitivity is 15dbm, you have approx 12-15db margin... using two muxes each with a 4.5db insertion loss, gives you 3-5db for other losses......but if your mux has an insertion loss of 6db then you will need to look at longer range optics, (higher tx power and higher rx sensitivity, resulting in more expensive optics). >Any particular vendors of the passive MUX, colored optics etc that you prefer >and have worked well? I have been happy and comfortable in working with the FiberStore (fs.com) There are other vendors which others have worked with. To me, after everything has clicked together in my understanding.... I now look at a passive mux in the same manner I would look at a Spool of Ethernet cable.. i.e. look at the specs, and the product, the cost, the name of the mfg. makes little difference other then consistency in delivery and standing behind the delivered product for the first 30/60 days. > It sounds like the costs are mainly the electronics to take the colored paths > and "convert" them back to normal wavelength if I'm not > missing something... Yep, bingo you are starting to understand it... And most important, don't forget to buy a Light Meter, it does not have to be anything fancy even a cheap one ($50) is good enough for deployment purposes, since you can get relative information from it. Regards. Faisal Imtiaz Snappy Internet & Telecom 7266 SW 48 Street Miami, FL 33155 Tel: 305 663 5518 x 232 Help-desk: (305)663-5518 Option 2 or Email: [email protected] ----- Original Message ----- > From: "Paul Stewart" <[email protected]> > To: [email protected] > Sent: Sunday, August 14, 2016 2:07:01 PM > Subject: Re: [AFMUG] DWDM Gear > Thanks very much - much appreciate this ... > > Optical stuff has always been a "weak area" for me ... worked around them for > years but 'spoiled' that we added X, Y, and Z per vendor recommendations along > with a web interface and things just worked ;) > > My comments re: colored optics though were very specific to what I consider an > "active" solution. A solution where we wouldn't have to put the colored > optics > specifically into switches on each side for example - realizing that the > optics > in the "solution" do the actual work .. I'm seen some passive systems where > you > have to put colored optics into your network gear for example. Those systems > were pretty cool though in the sense where you didn't have to power them at > all > - but that's not what we want to accomplish here .. a number of these fibers > we > don't "own" both ends for example. Using an 'active' solution we can jump > into > the middle of the fiber no problem but for handoff to the network itself we > need "standard" optics in place. > > For distance, this two locations with two paths so a ring topology .... one > path > is 1.1KM and the other path is approximately 3.2KM in length (geographic > diversity between locations, separate cable entranceways, separate risers etc) > so nice short run. Today we are just using 10KM single mode optics but > burning > fibers at a rapid rate .... > > Any particular vendors of the passive MUX, colored optics etc that you prefer > and have worked well? It sounds like the costs are mainly the electronics to > take the colored paths and "convert" them back to normal wavelength if I'm not > missing something... > > Again - thanks ... appreciate this and really like the "build your own" > approach > ... with savings expected it makes it easier to look at sparing etc too > > Paul > > > > > -----Original Message----- > From: Af [mailto:[email protected]] On Behalf Of Faisal Imtiaz > Sent: August 14, 2016 1:04 PM > To: [email protected] > Subject: Re: [AFMUG] DWDM Gear > > I just want to drill down, for the sake of an in-depth conversation, not just > for you but for others who are lurking as well... > > see my answers inline below:- > > Faisal Imtiaz > Snappy Internet & Telecom > 7266 SW 48 Street > Miami, FL 33155 > Tel: 305 663 5518 x 232 > > Help-desk: (305)663-5518 Option 2 or Email: [email protected] > > ----- Original Message ----- >> From: "Paul Stewart" <[email protected]> >> To: [email protected] >> Sent: Sunday, August 14, 2016 12:32:57 PM >> Subject: Re: [AFMUG] DWDM Gear > >> Thanks for that.... >> >> We want something managed and can be monitored ... > > There is no difference, or anything lost, in this arena, between an 'Active > Solution' vs a "designed/yourself passive" solution. > >> modular in nature if possible. > > There is no "Canned solution" that can beat the a 'designed passive solution' > in > this area. > > >> Thinking active as the "endpoints" (routers and/or switches) we do not want >> to >> utilize colored optics nor can we support it in some situations ... >> so MUX for sure. >> > > I think you are mis-understand how this actually works/gets implemented... > All CWDM/DWDM solutions have a passive fiber Mux/Demux in the box, the only > difference is what you see (out side the box) as optic options. > > e.g. each side just looks like this...... (passive mux/demux)---> {(Colored > optics <--> SMF Optics)in a managed Media Converter} > (One can use a managed modular media converter or a managed switch for > this). > >> While we operate a WISP, this is part of our core network in one city >> between two data centers so we want high quality > > There is nothing 'lost' or 'gained' in this area, only the perception of what > is > under the hood. > >> with a lower than we're used to price tag :) We would start with >> 40x10G likely and see how it goes > > Be prepaid for some serious pain to the wallet for lots of marketing BS to > justify that from those selling canned solutions. > Also pay attention to the Cost and power range of the required optics, (do you > power budget calcs due to insertion loss) > > My suggestion would be as follows:- > For a moment, forget about which solution you are going to buy, take a bit of > time to 'engineer' a passive solution, and just pencil in the figures, for all > the components... > > Use this as a baseline to value the solution you are actually looking to buy, > or > negotiate for... > > (when I do such an exercise, 40c DWDM mux/demux units are running less than > $2k > each, low insertion loss units(3-4.5db), 100mhz channels, Colored optics > (15db > margin) are under $300 each. You can add 10g SFP+/SFP+ media converter for > each > side ($900each) or you can add your favorite brand of 10g 48 port switches to > each side ...(running anything between $1000 to $1500 on the 2ndary markets). > > This would help in establish the value proposition and make you comfortable > with > what you end up going with. > > >> >> >> Thanks! >> Paul >> >> >> -----Original Message----- >> From: Af [mailto:[email protected]] On Behalf Of Faisal Imtiaz >> Sent: August 14, 2016 11:16 AM >> To: [email protected] >> Subject: Re: [AFMUG] DWDM Gear >> >> Technically speaking, there is no magic to CWDM or DWDM solution.... >> You can go with a 'canned' solution from folks such as Ciena/Cisco/etc >> etc etc or you can create your own with the required pieces, in the >> simplest form all one needs is couple of passive Mux/Demux units, >> colored optics and a Switch/Media Converters (ones that you can read the >> light >> levels from). >> >> Depending on length of the fiber, you may or may not need anything >> more (such as regen units, amps etc). If you are going to design a >> solution using passive Mux/Demux do pay attention to the insertion >> loss figures on the different products. >> >> In my opinion, doing a CWDM/DWDM design calculations for a WiSP should >> be fairly easy to understand. >> >> The benefit in designing your own solution, you gain a much better >> understanding on what you can do and what you cannot do... (e.g. do >> you know that you can potentially stack a DWDM solution right behind a >> CWDM passive mux ? .... and you will end up with a much more flexible >> solution, at a fraction of the cost of a comparable canned solution. >> >> We did a CWDM (8ch) passive solution, along with colored optics, 10g >> Switches between 4 different Data Center, for under $12k a couple of years >> back. >> They way we optimized our design for initial cost, while maintaining >> the ability to expand my adding another CWDM or DWDM mux in the future. >> >> (We went with gear from Fiberstore, we did consult them with our >> solution, and they offered us Mux/DeMux units with even lower >> insertion loss that those listed on their website for a slight >> premium, which in our case was well worth >> it) >> >> >> Faisal Imtiaz >> Snappy Internet & Telecom >> 7266 SW 48 Street >> Miami, FL 33155 >> Tel: 305 663 5518 x 232 >> >> Help-desk: (305)663-5518 Option 2 or Email: [email protected] >> >> ----- Original Message ----- >>> From: "Justin Wilson" <[email protected]> >>> To: [email protected] >>> Sent: Sunday, August 14, 2016 10:52:02 AM >>> Subject: Re: [AFMUG] DWDM Gear >> >>> Are you looking for active or passive? >>> >>> We just replaced a failing Ciena Mux with an 18 channel passive mux >>> for a data center client. Ours was CWDM, but they make a DWDM >>> version. Total cost was under 5 grand, including spares. Ciena >>> wanted 24k to update the service contract, update software, and >>> troubleshoot an alarm state. >>> >>> Justin Wilson >>> [email protected] >>> >>> --- >>> http://www.mtin.net Owner/CEO >>> xISP Solutions- Consulting – Data Centers - Bandwidth >>> >>> http://www.midwest-ix.com COO/Chairman Internet Exchange - Peering - >>> Distributed Fabric >>> >>>> On Aug 14, 2016, at 10:41 AM, Chuck McCown <[email protected]> wrote: >>>> >>>> I have always used Cyan. >>>> >>>> -----Original Message----- From: Paul Stewart >>>> Sent: Sunday, August 14, 2016 7:30 AM >>>> To: Animal Farm >>>> Subject: [AFMUG] DWDM Gear >>>> >>>> For those folks doing DWDM on fiber, whats your preferred equipment and >>>> why? >>>> >>>> We currently use BTI equipment which works extremely well but it’s >>>> priced in the same ballpark as Ciena, Nortel, Cisco etc … quite >>>> expensive to deploy. Hoping to find something more economical but >>>> just as reliable? By reliable I mean that it’s deployed for years >>>> without having to do anything service impacting to it. For this >>>> particular deployment I’m thinking of, ROADM isn’t important >>>> neither. Prefer active solution vs passive. CWDM would even be ok at >>>> this >>>> point to consider … >>>> >>>> Basically looking at ways to cut down on 10G fibers between two >>>> physical locations (the fiber is leased) >>>> >>>> thanks, > > >> Paul
