Designers, installers, and operators of fiber networks with MPO connectivity highlight trends and challenges.
MPO Connector Testing
MPO Connector Efficiency
Multi-fiber Push On (MPO) connectors increase your data capacity with a highly efficient use of space. But users have faced challenges such as extra complexities and time required for testing and troubleshooting multi-fiber networks. VIAVI helps overcome these challenges with the industry's most complete portfolio of test solutions for MPO connectivity.
Essentials of Multi-Fiber (MPO) Connector Testing
While MPO connectors have many benefits and advantages over typical single fiber connectors, there are also differences that introduce new challenges for technicians. This resource page provides an overview of the essential information technicians must understand when testing MPO connectors.
MPO Testing Challenges
Performing MPO inspection and enterprise testing with tools designed for single fiber applications can be cumbersome and time consuming. With native MPO now running directly to switches, routers and servers in 40/100 Gig applications, advanced testing becomes more essential thus necessitating test equipment with native MPO ports to efficiently test these links and channels.
Inspecting MPO connectors with conventional single fiber inspection tools can difficult because the MPO interface presents unique access and geometry challenges. Dedicated MPO inspection tips can be added to microscopes designed for single fiber connections, but this adaptation process can be time-consuming. An autonomous multi-fiber inspection solution can adequately address the importance of end face inspection in MPO applications, while further automating the inspection practice.
Tier 1 length, loss and polarity testing can be performed with a traditional OLTS and break-out cables from the LC or SC input ports, but this process is improved significantly simply through the introduction of dedicated MPO OLTS equipment. Similarly, OTDR test equipment with dedicated MPO switch ports can conveniently cycle multiple fibers through advanced testing processes
To learn more about MPO connector testing challenges, watch our “MPO Testing” video posted in the above section.
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Tyler Vander Ploeg: Hi everybody. I'm Tyler from VIAVI Solutions. And in this episode I'm talking with Ed Gastle. He's our product line manager for many of our fiber optic test equipment. And he also oversees many of our MPO test instruments. So I wanted to have some time to talk with him a little bit about the different portfolio that we have and what testing is used and when. So Ed, thanks for being on with us.
Ed Gastle: Thanks, Tyler.
Tyler Vander Ploeg: So tell us a little bit when it comes to MPO testing, I know it's been around for a long time, but a lot of folks who are getting into this are asking, okay, what do I need? What kind of test equipment do I need for MPO?
Ed Gastle: MPO testing is not that much different than regular duplex fiber testing in the sense of what tests need to be performed. Obviously the testers are somewhat different. So for the test that you need to perform, you've got your straight on inspection of the fiber end faces and of course it's typically a 12-fiber fair that you have to inspect. You've got your tier one or basic fiber certification, which is your loss, length and polarity. And you also have your tier two or your enhanced testing, which is performing OTDR tests so that you can really see each individual event in that fiber link. So that's really, it's the exact same that you would see for duplex testing. It's just that your tools have to be different because you've got a different fiber connector, being that MPO connector.
Tyler Vander Ploeg: Great, yeah. So we've talked a lot, obviously, about fiber inspection on other episodes and such, but I want to ask a little bit more about when it comes to, you talked about length, loss, and polarity, differentiating when to use a typical MPO to MPO test versus maybe, I know there's applications where MPO is a subset of a greater link. Can you talk a little bit more about when you'd need to use direct MPO testing versus others?
Ed Gastle: Yes. So this is, MPO really has been in networks for quite some time and it's been used as a backbone or a trunk. When you have that backbone or a trunk, then you'll typically have something like a cassette to break down into individual LCs. And those, that still exists and that will get you up, in today's world with multimode, will get you up to 10 gig. If you start to go beyond 10 gig, then you start to need to have different types of connectors out at the end. So that's, this is your cassette. You've got your 24 fibers coming in at the back through MPO, and these need to be inspected. But then your test is done with a classical LTS by testing each of the individual LC drops. So in this case you really don't need to test the trunk assembly. If you do need to troubleshoot it, that's where an OTDR would come into play, and then you can look to find out where a specific fault is. But typically with those trunk assemblies, your issue is your connections that you have, the MPO connections.
Ed Gastle: So then when things start to get different is where you're running at, especially with multimode, 40 and 100 gig, and there are systems like PSM4 for single mode that also run what I would call native MPO right into the equipment, whether it's a switch, a router, a server type of thing. And for that, then you need to start having native MPO interfaces on your test equipment which allow you to test those links and channels. So that's what the, in this case, the MPO LX does, is your basic or tier one certification, your loss, length and polarity. And it's done really much the same way that you would do with an OLTS on LC links. As you do a set reference. You set a limit and then you connect up to your system that you're testing. You perform the test. You get pass/fail. Except you're doing a pass/fail on 12 fibers now instead of two.
Tyler Vander Ploeg: Gotcha. Okay. So very similar behavior. It's still an optical loss test set.
Ed Gastle: Exactly.
Tyler Vander Ploeg: Now, and you said this is more prevalent when you get into that 40 gig, 100 gig with QSFPs and such.
Ed Gastle: With QSFPs, where you've got that direct QSFP or MPO connection into your switch and servers. That's where you need to be, now your link itself, instead of being a duplex LC, your link is an MPO. Typically a 12-fiber MPO. And that's why you need to test that length with native MPO testing. Or you can test the channel as well. Disconnect from the QSFP plugged into the switch, server, router, whatever, and then test the channel.
Tyler Vander Ploeg: Okay. You had briefly mentioned the tier two or enhanced testing as well. Finding out more information. How do you, can you talk a little bit more about some of the new technologies with being able to test an MPO individual lanes with an OTDR.
Ed Gastle: So with our 4000 platform, we have a switch module for it. So your OTDR is still a simplex connection, but the simplex connection goes to the switch and the switch gives you that 12-fiber MPO out and because the MPO switch module and the OTDR module are both on the same device, it's really automated. So you say what you want to test. I want to test all 12 fibers. You hit start, and the OTDR tests fiber number one. The switch switches to fiber number two. Test fiber number two, and so on.
Ed Gastle: So you just start it, step back and let it go through all 12 fibers in a, by stepping through with the switch.
Tyler Vander Ploeg: And again, like any OTDR, that gives you the benefit of seeing each individual event through that entire-
Ed Gastle: Correct. And with modern OTDRs, you're, certainly the 4000, is that you're then seeing a schematic view so that you see what the events are and which events have a problem with it instead of having to read a squiggly line on a screen.
Tyler Vander Ploeg: That's perfect. Well, hey, thanks again for joining us, Ed. You also recently wrote a white paper.
Ed Gastle: I did.
Tyler Vander Ploeg: That goes into great depth on this.
Ed Gastle: Yes.
Tyler Vander Ploeg: For more information and to get that white paper that Ed wrote, you can visit us online at viavisolutions.com/mpo. Thanks for watching.