Cambium's very limited SFP range is a joke!

Products PTP
1

Any ideas on the SFP debacle that Cambium are only licensing 2 SFP's?

We are happy to pay for 'Cambium' SFP and licence but the range supplied is a joke, surely they can relicence the whole cisco/jdsu range so we can use them?

If they are worried about losing money to having 10+k SFP's like 20/40/70km then don't offer those but only offering two SFP's is a joke! Most industrial switches  with mulimode work on 10/100 and  1300nm but cambium offer only  850 nm / 1000 BaseSX; 

Another 'feature' which Cambium have taken the usefulness out!

2

Thanks for your comments on the SFP option in PTP 650. I can tell that you're not 100% convinced by the options we offer.

We actually offer three different SFP upgrades:

- 1000BASE-LX optical SFP for single mode on 1310 nm wavelength (C000065L008)

- 1000BASE-SX optical SFP for multimode on 850 nm wavelength (C000065L009)

- 1000BASE-T or 100BASE-TX copper SFP (C000065L0010)

In each case, the upgrade includes the appropriate SFP module, an extended cable gland for environmental sealing and strain relief, and an entitlement to generate a License Key with the SFP capability.

I'm not sure why you think we support only 850 nm.

We're not aware of any optical SFP modules that support more than one data rate, and the modules we supply only support gigabit operation. If you can identify some multi-rate optical SFP modules we'd be happy to investigate further. Also, if you really need 100 Mbit/s operation on fiber, you're welcome to submit a feature request.

As you point out, there are many different gigabit optical SFP modules on the market. Whilst they appear similar, they are not always interchangeable. We have tested the parts that we supply to be certain that problems will not arise in operation. We think this is an effective way to support our customers. Other SFP modules in the same format might well work, but we can't provide much support if you use other parts.

The situation with the copper SFP is a bit different. The ODU has to configure the Ethernet PHY by writing to registers in the module, and the details of this vary significantly between different manufacturers. Copper SFPs are not interchangeable in PTP 650, and we actively reject use of parts that we have not tested.

1 Like
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@mike11 wrote:

Any ideas on the SFP debacle that Cambium are only licensing 2 SFP's?

We are happy to pay for 'Cambium' SFP and licence but the range supplied is a joke, surely they can relicence the whole cisco/jdsu range so we can use them?

If they are worried about losing money to having 10+k SFP's like 20/40/70km then don't offer those but only offering two SFP's is a joke! Most industrial switches  with mulimode work on 10/100 and  1300nm but cambium offer only  850 nm / 1000 BaseSX; 

Another 'feature' which Cambium have taken the usefulness out!

page 2-42 of the user manual have them listed... I've never seen a 5km tall tower, but someday it might happen... 

and as cambium said, you can try other SFPs   other brands do work, they just can't guarantee reliability... like every other vendor out their says. 

1 Like
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@Mark Thomas wrote:

Thanks for your comments

I'm not sure why you think we support only 850 nm.

As referenced in post, I'm looking for a 1300nm multimode SFP , the only multimode SFP offered by Cambium as you quite accurately rightly in the same post is the  - 1000BASE-SX optical SFP for multimode on 850 nm wavelength (C000065L009) that operates in 850nm not 1300nm.

@Mark Thomas wrote:

We're not aware of any optical SFP modules that support more than one data rate, and the modules we supply only support gigabit operation. If you can identify some multi-rate optical SFP modules we'd be happy to investigate further. Also, if you really need 100 Mbit/s operation on fiber, you're welcome to submit a feature request.

As you point out, there are many different gigabit optical SFP modules on the market. Whilst they appear similar, they are not always interchangeable. We have tested the parts that we supply to be certain that problems will not arise in operation. We think this is an effective way to support our customers. Other SFP modules in the same format might well work, but we can't provide much support if you use other parts.

The GLC-FE-100FX-RGD work in both fast ethernet and gig ports whilst running 100base FX and the GE variant works in gig ports, have tried, ive got a dozen different SFP's on hand to trial and purchased a few more yesterday.

@Chris_Bay wrote:

page 2-42 of the user manual have them listed... I've never seen a 5km tall tower, but someday it might happen... 

and as cambium said, you can try other SFPs   other brands do work, they just can't guarantee reliability... like every other vendor out their says. 

Cambium don't actually say, "try other SFP's" they lock down / licence SFP ports and then sell only 3 SFP options, 2 of which being Fiber. I don't have a problem with paying for the 'licence' but need more supported SFP's

Yes, Towers might not be 5km tall, but if that's all you've got to worry about you are sorted. Radios are often 5km + from existing networks, 

I do not have a R+D engineering TEAM on hand that a tech company the size of Cambium would have many divisions, I'd think with the latest 5G fiber to the radio networks being deisnged that Cambium would be all over the use of fiber to the radio - fiber SFP ports - but instead Cambium offer 2 fiber SFP's. I understand a company like CISCO will only support CISCO SFP's but consider the range they offer, its closer to 50 than 2.

I'm happily putting my own time and money into researching this as Cambium haven't,  or they have and don't want to put the info out there. 

I've bought 2x PTP650's just for testing, I've bought a bunch of switches and SFP's to emulate what I'm trying to create. As Cambium couldn't assist with info they have sent me a licence yesterday to test a unit so getting somewhere and hopefully it works but the limitation of what is sold / supported is a joke SFP wise, the PTP650 radio's are brilliant otherwise.


 

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Thanks. That clarifies some aspects of the original post.

You're looking to use multimode cable at 1310 nm wavelength. Cambium doesn't supply a suitable SFP transceiver for this combination. As far as I know, this hasn't been a problem in the past.

As we pointed out before, the upgrade includes the extended gland and the entitlement to enable the SFP port on the PTP 650. The license simply enables the port; it doesn't lock the ODU to any particular optical SFP module.

Of course, Cambium does not manufacture SFP modules. We simply selected some suitable parts and tested them to ensure compatibility. Figure 23 in the PTP 650 User Guide shows a JDSU part. You can see details of the SFP modules installed by looking at the SFP Configuration page in the web-based interface.

Fiber SFP modules are actually quite simple, essentially consisting of an optical transmitter and receiver, a basic controller, and not much else. We checked out the datasheets for the GLC-FE-100FX-RGD and GLC-GE-100FX. These parts work at 125 Mbit/s over fiber. We believe that the 100BASE-FX parts will not work in PTP 650, because of a data rate mismatch, since the PTP 650 Ethernet physical layer for the fiber SFP only transmits and receives serial data at 1.25 Gbit/s. Nevertheless, we have ordered some of these parts in case there is more to this than meets the eye. We'll post the results when the parts arrive.

Please keep us up to date with results of your tests.

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Hi Mark

Thanks for your time in responding to these, I see you are in touch with other Cambium personel so good to see this might end up with a solution with SFP port supporting 100mb. Though I think you have missed the the point, the point isn't to whinge, the point being that Cambium, by following the Cambium business model and licensing out everything, only support two fiber SFP modules, that remian undocumented in any Cambium literature.

Yes - I realise Cambium do not make SFP's! Cambium also do not make the PTP820 but they happily licence out Ceragon units? Surely they can stick a Cambium badge on top of bunch of Finisar SFP's etc?

Yes, I have seen on various vendors websites that they may sell a JDSU SFP, with a poor quality picture that you can not read any part numbers, but there is no documentation associated with it, as there is no documentation with the SFP licencing that clearly states, you can "use any compatible SFP". The only documentation is that you can buy a licence to use a SFP supplied by Cambium. Don't forget the gland... The closest thing is this thread in the Cambium community pages!

Through various emails we have discovered that the Licence may open up many different SFP's options but only 1gbps SFP, which is unfortunate considering the amount of production equipment that still operates on 100mb. It is also unfortunate that it is not backwards compatible. Going from various Siemens/Moxa/Hirschmann industrial 100mb switches fiber ports to a 1000mb SFP port on a cosco switch with a Cisco RGD FE / GE I can get a link, but plugging the same SFP into the PTP650  I get a link light up and 1000mb green status but can not ping/pass traffic over it. A limitation on the PTP650 I believe.

I have done testing with a bunch of singlemode/1310 1gbps SFP's and am happy to add to a data base of what I have found worked, but I am yet to see any database or list of supported SFP's. Is there one you are aware of? I must need a different SFP licence to use a copper SFP as none of the copper 10/100/1000 SFP's I used worked.

I think the fiber to the radio will come into use a lot more in the coming future for the simple reasons of, no intereference to signal and potential to go xx kms distance from source.

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As you have demonstrated, most 1 Gbit/s fiber modules will work with PTP 650. We haven't tested them all, but these modules are designed to be more or less interchangeable.

Usung the 100BASE-FX modules is a bigger problem; the circuitry in the PTP 650 is expecting serial data from the SFP module at 1.25 Gbit/s, whilst the 100BASE-FX modules provide serial data at 125 Mbit/s. Unless we missed something, this combination is not going to work without a significant redesign of the PTP 650.

The situation with the copper SFP is a bit different. In this case, the Ethernet PHY is in the module, and connects to the ODU using an SGMII interface. The ODU has to configure the Ethernet PHY by writing to registers in the module, and the details of this vary significantly between different manufacturers. Because of this, copper SFPs are not interchangeable in PTP 650, and we actively reject use of parts that we have not previously tested. In principle, we could add additional modules to the list of supported modules, but we would first have to check out the exact register settings and do some testing.

We are going to investigate a further possibility. A few optical SFP modules are available for 100BASE-FX, where the Ethernet PHY is in the module and the interface to the host (the PTP 650) is SGMII. Because of this interface, the modules connect to the PTP 650 in the same way as copper SFPs. These are likely to be rejected by the existing firmware as unrecognised copper SFPs, so some firmware changes will be needed. We'll let you know how we get on.

8

Hi

Any luck with the tests your were doing?

The ones I did wouldn’t work with the PTP650 but would work with other 1Gbps SFP ports.

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There are two cases to consider. Most of the 100 Mbit/s fibre SFPs provide a simple serial interface to the host, and we knew that these would not work in PTP 650, because the circuit expects to see a 1.25 Gbit/s stream, and will not work with a 125 Mbit/s stream. Maybe other network equipment is more flexible than PTP 650 and adapts to either rate.

The second case is with a less common type of SFP module that provides 100 Mbit/s interface to the fibre, a built-in fibre PHY layer, and an SGMII interface to the host. This makes the module appear to the host as similar to a copper SFP. We experimented with some of these modules, but unfortunately could not get them to work in PTP 650.

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I have to agree this is kind of ridiculous in this day and age to lock down the sfp ports on a piece of equipment like this. If you were a switch vendor it would make a little more sense. Why not just sell the license and code the port to accept any MSA standard optic. This is pretty much the industry standard today.

The comment of who has a 5km high tower  lacks any ingenuity in thinking. There are many more purposes today to deploy equipment other than standard macro towers. These are great devices to use on small cell type deployments which may only be 6o feet tall but can be 10 miles from the switch.

another big use for other optics up a tower are BIDI transceivers. These are very useful if you already have fiber up a tower and are limited to the number of strands. It is also much easier to use common components like drop cable and Splice on SC connectors for cables up the tower. This most common hardware is singe fiber drop cable and SC APC connectors.

My question is if we buy the kit is there still anything that would prevent someone from using there own optics. It really does nothing to lock them down anyway as it is not that difficult to re-code one to look the same as the Cambium.

11

Hi Trey,

We sell three upgrade kits with either single mode fiber, multimode fiber or copper SFP modules. The kits contain the SFP module, an extended housing and gland, and an entitlement to activate the SFP port. You can't use the SFP port without one of these upgrades. The kits contain an SFP module from a limited range that we have tested, and that we can confidently support.

Gigabit fiber SFP modules are essentially quite simple devices and are normally interchangeable. If you would like to use a different part, it will most likely work satisfactorily. If you try a different part and it doesn't work we would like to know more details. There is no sense in which we have "locked down" the ports for fiber SFP modules. I'm not sure why you think this is the case.

In Message 4, mike11 mentions that he was trying to use 100BASE-FX modules. These operate at 100 Mbit/s and are not compatible with the circuits in the PTP 650/670/700. We identified some alternative 100BASE-FX modules that supposedly emulate a copper SFP module and experimented with these parts, sadly without any success. Unfortunately we couldn't come up with a solution to the 100BASE-FX problem without doing significant additional development.

Gigabit copper SFP modules are a different proposition. Here, the module includes the Etherent physical layer and the module must be configured by the ODU. This interface is not completely standard, and the ODU has to configure each module differently. Here we do take steps to limit the modules that can be used, so it would be fair to say that we have locked down the choice of copper SFPs. However, it appears that most customers using the SFP port are using fiber, for sensible and understandable reasons.

Now for the question of single fiber modules: As things stand, this will probably work if your SFP module has an LC connector. When the ODU fails to find an LC connector it assumes a copper RJ-45 connector, which is obviously not appropriate. If there is demand for bidirectional operation with an SC connector, we might look to introduce support in a future release.

Mark