ፎርም ፋክተሮች፦ አጠቃላይ እይታ እና ንጽጽር
ቡድናችን በትርጉሙ ላይ እየሠራ ነው። ይህ ጽሑፍ ለጊዜው በአማርኛ አይገኝም፤ ስለዚህ በእንግሊዝኛ ቀርቧል።
An optical transceiver's form factor fixes its size, connector, electrical interface, lane count and — crucially for CodingBox — the management specification that defines where every field lives in module memory. CodingBox supports the 14 form factors below; each has its own reference page.
The single-lane family (SFP lineage)
| Form factor | Lanes × rate | Total | Management | Typical use |
|---|---|---|---|---|
| GBIC | 1 × 1G | 1G | GBIC MSA serial ID | legacy 1GbE, 1GFC |
| SFP | 1 × up to ~4G | 1–4G | SFF-8472 | 1GbE, 1/2/4GFC, SONET |
| SFP+ | 1 × 10G | 10G | SFF-8472 | 10GbE, 8/16GFC |
| SFP28 | 1 × 25G | 25G | SFF-8472 | 25GbE, 32GFC |
| SFP56 | 1 × 50G (PAM4) | 50G | SFF-8472 | 50GbE, 64GFC |
| SFP-DD | 2 × 25/50G | 50–100G | SFP-DD MIS 2.0 | 100G in an SFP footprint |
| XFP | 1 × 10G | 10G | INF-8077i | 10GbE, OC-192 (legacy) |
The four-lane family (QSFP lineage)
| Form factor | Lanes × rate | Total | Management | Typical use |
|---|---|---|---|---|
| QSFP | 4 × ~2.5–5G | up to 20G | SFF-8436 | early InfiniBand, 4×1G |
| QSFP+ | 4 × 10G | 40G | SFF-8636 | 40GbE, IB FDR |
| QSFP28 | 4 × 25G | 100G | SFF-8636 | 100GbE, IB EDR, 128GFC |
| QSFP56 | 4 × 50G (PAM4) | 200G | SFF-8636 / CMIS | 200GbE, IB HDR |
| QSFP112 | 4 × 100G (PAM4) | 400G | CMIS | 400GbE, IB NDR |
The eight-lane family (double density)
| Form factor | Lanes × rate | Total | Management | Typical use |
|---|---|---|---|---|
| QSFP-DD | 8 × 50/100G | 400G / 800G | CMIS | 400GbE/800GbE, AI fabrics |
| OSFP | 8 × 50/100G | 400G / 800G | CMIS | 400GbE/800GbE, IB NDR |
| OSFP224 | 8 × 200G | 1.6T | CMIS | 1.6TbE, IB XDR (200G lanes) |
| OSFP-XD | 16 × 100G / 200G | 1.6T / 3.2T | CMIS | 1.6T switch ports, AI fabrics |
Three generations of management
- Two-address (SFF-8472) — SFP-class modules expose identity at A0h and diagnostics at A2h. See SFF-8472.
- Paged (SFF-8636) — QSFP-class modules use one address with a lower page and selectable upper pages. See SFF-8636.
- CMIS / MIS — QSFP-DD, OSFP, QSFP112 and SFP-DD use the form-factor-independent CMIS model (or its SFP-DD sibling MIS) with banked pages and a module state machine. See CMIS and MIS.
Codes shared by all of them — identifiers, connectors, interface codes — live in SFF-8024.
Why it matters
The form factor tells CodingBox which decoder to apply, so identity and DDM are read from the right addresses; reading an SFP as if it were a QSFP would misinterpret every field. CodingBox detects the form factor automatically. How a module protects its memory is a separate axis — see Write-protection types & programming.
Which cages accept which of these form factors, and what speeds the port behind the cage can run: Port types and cages.
Power class ladders and real consumption for each form factor: Power & consumption.
Which of these form factors and PMDs fits which fibre, distance and connector — the matching table from the plant's point of view, with the common module-to-plant mismatches: Transceivers in the link.