MPO-12/APC OM4 Multimode Trunk Cable, Type B, Female-to-Female — for NVIDIA NDR 400G/800G Optics

NDR optics require APC. The UPC cords from your 100G or 200G fabric will not mate with them.

This is an MPO-12 trunk cable with angle-polished (APC) endfaces, built to the polarity and gender NVIDIA NDR-generation optics actually need: Type B crossover, female/unpinned on both ends, all 12 fibers terminated. OM4 50/125 multimode, aqua jacket, green connector housings, OFNP plenum rated.

If you are populating an MMA4Z00-NS400, an MMA1Z00-NS400 or an MMA4Z00-NS, this is the cable.

APC vs UPC — read this before you order

An APC connector has an 8° angled endface. A UPC connector is flat. They cannot mate. Put them together and you get an air gap, an unusable return loss figure, and a link that either never comes up or comes up and drifts.

The 100G (4×25G NRZ) and 200G (4×50G PAM4) generations were overwhelmingly UPC. NDR 400G and 800G moved to APC. A customer upgrading an existing fabric does not carry their patch cords forward. This is the most common ordering mistake in an NDR upgrade, and most supplier pages never mention it. The full MPO-12/APC vs UPC guide is here.

How to tell at a glance: a green connector housing means APC — NVIDIA's own module documentation describes the MPO-12/APC interface as having a green plastic shell. The jacket color tells you the fiber type — aqua is OM3/OM4 — not the endface. Two different things, easy to conflate, and jacket colors vary between manufacturers. The connector housing is the reliable answer.

Key orientation: key-up to key-down

The industry shorthand "Type B means key-up to key-up" is a UPC rule, and it does not transfer to APC. Two 8° angled endfaces have to be complementary to seat, so an APC Type B assembly mates key-up to key-down — Modified Method B, a Type B cable through Type A (key-up/key-down) adapters.

This cable is built key-up to key-down, confirmed in writing by the manufacturer. Worth checking whatever else you are buying: it is not unusual to find a part listed as APC and "female key-up to female key-up" on the same page, which cannot physically mate.

Fully terminated 12-fiber — and why that is a feature

All twelve positions are terminated in a Type B crossover: position 1 lands on position 12, 2 on 11, and so on across the connector.

An SR4 module uses four lanes in each direction. NVIDIA's own MFP7E10 multimode cable is built with eight fibers populated — positions 1–4 and 9–12, with 5–8 left unconnected — because that is all an SR4 link needs. Ours terminates all twelve. In an SR4 link the two are interchangeable: the module's four transmit positions land on the far end's four receive positions either way, and the extra pairs simply carry no traffic.

The difference shows up later. A fully terminated assembly can be re-tested end to end, can carry a different lane map if you repurpose it, and does not leave you guessing which positions were populated when a link goes marginal two years from now.

Which one do I need?

OSFP does not go in a BlueField-3. NVIDIA states that BlueField-3 adapters accept QSFP112 devices only, so a BlueField-3 takes the MMA1Z00-NS400, not the OSFP MMA4Z00-NS400. The fiber is the same either way — this cable serves both.

Twin-port rule: both ports on a twin-port module must run the same fiber type. Do not mix a straight cable in one port and something else in the other.

Technical specifications

Pricing by length

Volume: 10 or more of any one length, 10% off. 25 or more, 18% off. Quoted at checkout or on a pod quote.

Good to know

• Female/unpinned is correct. NVIDIA's SR4 and SR8 modules carry the alignment pins; the fiber connector carries the matching holes. Pinned MPO connectors belong on permanent-link backbone cabling that lands in a patch panel, not on the cable that plugs into an optic.
• OM4 at every length. NVIDIA's own MFP7E10 assemblies are specified OM3 at 30 m and under, OM4 only above 30 m. Every length here is OM4, including the 1 m — more margin in the link than the OEM part gives you at the same distance.
• OFNP, not riser. This cable is plenum-rated. NVIDIA's MFP7E10 assemblies are specified LSZH-OFNR — riser. If your run crosses a plenum air-handling space, OFNR is not code-compliant and OFNP is.
• The connectors are the loss budget. At data-center distances the fiber itself contributes almost nothing. Nearly all of your loss sits in the mated pairs, which is why low-loss grade matters more here than length does.
• Derate the reach. The 50 m OM4 figure on NVIDIA's SR4 modules — 30 m on OM3 — already assumes patch panels in the link, which is four connector junctions. It is not 50 m of clean fiber with headroom on top. More hops means less usable distance.

Quick checklist — is this the right cable?

Your optics are NDR-generation and take MPO-12/APC. Your fiber plant is multimode (OM3/OM4). You need a straight cable, not a 1:2 splitter. Your run still fits its loss budget with four connector junctions in the path.

If you do need a splitter — one twin-port 800G switch port feeding four adapters at NDR200 — we build those to order in multimode or single-mode, to your leg lengths.

Availability

In stock at Resilient Tec.

Shipped from Knoxville, Tennessee. Free standard shipping on all US orders, no minimum. Populating a pod? Tell us your node count and module part numbers and we will quote the cables and the optics together. Request a quote →

Warranty: lifetime, backed by Resilient Tec — not a manufacturer term. When something fails you reach a named seller in Knoxville, not a ticket queue.

You might also need

• 400G OSFP SR4 (MMA4Z00-NS400) — the NIC-side module this cable plugs into
• 400G QSFP112 SR4 (MMA1Z00-NS400) — the same optics for BlueField-3 and ConnectX-7 QSFP112 adapters
• 800G OSFP SR8 (MMA4Z00-NS) — the switch-side module, two cables per unit
• MPO-12/APC OS2 single-mode trunk cable — for DR-class single-mode modules
• MPO-12/APC 1:2 splitter cables — built to order, for NDR200 fan-out from a twin-port switch port
• MPO-12/APC vs UPC: why your existing fiber won't work with NDR optics — endface, pinning, polarity and key orientation in full
• NVIDIA OSFP part-number crosswalk — pin down the exact optic behind a part number before you order fiber for it
• OSFP DAC cables — for in-rack runs where copper is the better answer than fiber
• Transceivers — the rest of the optics catalog