Wired Intelligent Edge

Dear all,

the J4858D is compatible with both the 2930F SFP+ and the 2930m SFP slots.
Regarding the Fiber media, on the document "ArubaOS-Switch and ArubaOS-CX Transceiver Guide (Edition 11) December 2021" link https://community.arubanetworks.com/HigherLogic/System/DownloadDocumentFile.ashx?DocumentFileKey=a2a1fdd8-1f45-4a13-b95e-0284ede0c394

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it is reported that the J4858D supports a maximum distance of 550 meters over an OM2 fiber.



Will two of these SFPs work on a OM3 fiber, 850 nm, 50/125, (jacket color acqua)?

If yes, at which maximum distance?

All in all: a 2930F on one side with a J4858D ina SFP+ slot, a 2930M on the other side with a J4858D ina SFP slot, approx 300 meters of OM3 fiber, will it work at 1G?

Thanks in advance to everyone who will provide useful information and their experiences.

GG

Hi. Yes, it should work at 1G :)


I hope this helps.

"If yes, at which maximum distance?"

For sure at the very same maximum distance capable when using tested OM2 MMF cables (50/125 um 850 nm), so up to 550 meters.

That's to say that using OM3 MMF or, better, OM4 MMF cables helps enhancing overall performance of optical signals and, probably, considering that, a valuable length can unofficially gained over the official 550 meters threshold value...but not so long (at some point shifting to SMF over MMF become a must if you have a long run) and nothing in that territory, in term of admissible official working values, should be taken for granted (somewhere - here as example - I saw reported a maximum distance of maybe 800/1000 meters, at best...and those values are not related to an Aruba SFP 1G SR Transceiver...indeed those values are not coming from something tested and declared by Aruba as per published standards...and indeed Aruba doesn't report those values too, see here a discussion about what is granted and what's not on MMF with SFP SR Aruba Transceivers).

A 300 meters run, especially deployed with OM3 MMF, should be an easy run for two J4858D so I believe you can expect 1Gbps Full Duplex without issues if optical cabling and patches is correctly deployed, tested and so certified.

Thank you Ulises for the confirmation and thank you Parnassus for your detailed explanation.

Yes, we will stay well below the 550 meters, and possibly under the 330 meters that will enable us one day to upgrade to 10G Short Range without replacing the fiber, ony replacing the switches and their SFPs.

Thank you again and Regards
GG
Original Message:
Sent: Oct 31, 2022 01:29 PM
From: Davide Poletto
Subject: Aruba 1G SFP LC SX MMF (J4858D) and OM3 fiber

"If yes, at which maximum distance?"

For sure at the very same maximum distance capable when using tested OM2 MMF cables (50/125 um 850 nm), so up to 550 meters.

That's to say that using OM3 MMF or, better, OM4 MMF cables helps enhancing overall performance of optical signals and, probably, considering that, a valuable length can unofficially gained over the official 550 meters threshold value...but not so long (at some point shifting to SMF over MMF become a must if you have a long run) and nothing in that territory, in term of admissible official working values, should be taken for granted (somewhere - here as example - I saw reported a maximum distance of maybe 800/1000 meters, at best...and those values are not related to an Aruba SFP 1G SR Transceiver...indeed those values are not coming from something tested and declared by Aruba as per published standards...and indeed Aruba doesn't report those values too, see here a discussion about what is granted and what's not on MMF with SFP SR Aruba Transceivers).

A 300 meters run, especially deployed with OM3 MMF, should be an easy run for two J4858D so I believe you can expect 1Gbps Full Duplex without issues if optical cabling and patches is correctly deployed, tested and so certified.