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What payment methods do you accept?

We accept the following payment methods:Credit/Debit Cards: Visa, MasterCard, American ExpressPayPal: Secure online paymentWire Transfer: Bank transfer for bulk/wholesale ordersWestern Union: Available for international customersAll payments are processed securely. Your information is encrypted.

What is your shipping policy?

We offer worldwide shipping:Express (DHL/FedEx/UPS): 3-7 business daysAir Mail (China Post): 15-25 business daysSea Freight: Available for bulk wholesale ordersOrders processed within 1-2 business days after payment. Free shipping available for qualifying orders.

Do you offer OEM/ODM services for fiber optic products?

Yes, we offer OEM and ODM services:OEM: Custom branding with your logo and packaging on existing productsODM: Custom product design based on your specificationsCustomization: Custom cable lengths, connector types, and packagingMOQ varies by product (typically 50-100 units). Contact our sales team for a quote.

What is the difference between GPON and EPON?

GPON offers higher downstream bandwidth and better QoS. EPON provides symmetric bandwidth at lower cost. GPON supports split ratios up to 1:128 for wider coverage.

Which ONU/ONT is compatible with my OLT?

Our L880G and L801 series ONUs support XPON dual-mode and work with Huawei, ZTE, FiberHome and other major OLT brands. Contact support to confirm compatibility.

What is the difference between SC/APC and SC/UPC connectors?

SC/APC (Angled Physical Contact) and SC/UPC (Ultra Physical Contact) are two common fiber optic connector polish types. The key difference is the end-face angle.SC/UPC: Flat end-face with slight curve, return loss ≥50dB. Used for general-purpose data transmission. Blue color.SC/APC: 8° angled end-face, return loss ≥60dB. Used for RF video transmission (CATV) and PON networks. Green color.They are NOT interchangeable — mixing them can damage the connector end-face.

How do I choose the right fiber optic splitter for my network?

Choosing the right fiber optic splitter depends on several factors:Type: PLC splitters offer better performance for FTTx; FBT splitters suit smaller setupsRatio: Common ratios: 1×2, 1×4, 1×8, 1×16, 1×32, 1×64Package: ABS box (indoor), Mini steel tube (tight spaces), LGX cassette (rack mount)Connector: SC/APC for CATV, SC/UPC for dataFor GPON/EPON FTTH deployments, a 1×8 or 1×16 PLC splitter with SC/APC connectors is recommended.

What is the maximum distance for fiber optic transmission?

Fiber optic transmission distance depends on fiber type and equipment:Single-mode fiber (OS2): Up to 40km+ without amplificationMulti-mode fiber (OM1-OM5): 300m to 550m at 10GbpsGPON: Typically 20km reachEPON: Typically 20kmXGS-PON: Up to 40km1550nm wavelength has lower attenuation (≈0.2dB/km) vs 1310nm (≈0.35dB/km). For standard GPON FTTH, 20km is typical from OLT to ONU.

How do I configure an ONU/ONT for my fiber network?

Configuring an ONU/ONT involves these steps:Connect: Plug fiber cable into PON port, Ethernet to your router/PCPower on: Wait for PON LED to turn solid (optical signal received)Access web: Set PC to same subnet (192.168.1.x), open ONU IP (usually 192.168.1.1)Configure WAN: Set connection type (PPPoE, DHCP, or Static IP) per ISP requirementsRegister: Some ISPs require registration via serial number, LOID password, or MAC address

What is XGS-PON and how is it different from GPON?

XGS-PON (10 Gigabit Symmetric PON) is the next-generation PON technology offering 10Gbps symmetric bandwidth. Key differences from GPON:Speed: GPON = 2.5Gbps down / 1.25Gbps up. XGS-PON = 10Gbps both directionsWavelength: XGS-PON uses 1577nm down / 1270nm up (different from GPON's 1490nm/1310nm)Coexistence: XGS-PON can share the same fiber with GPON via WDMXGS-PON ONUs work with dual-mode OLTs but need an XGS-PON port for 10G speeds. Ideal for 4K/8K streaming, cloud computing, and enterprise use.

How Many Homes Can One OLT Port Serve?

In GPON networks, one OLT port typically serves 32 to 128 homes, depending on the split ratio. A 1:32 splitter is most common for FTTH deployments. With XGS-PON, one port can serve 256+ subscribers. Actual capacity depends on bandwidth per user — if each user needs 100Mbps, a GPON port (2.5Gbps down) handles ~25 users at peak. For our 2-port EPON OLT (L202), each port supports up to 64 ONUs, giving a total of 128 homes per device.

How Is GPON Data Secured on Fiber Optic Networks?

GPON uses AES-128 encryption to secure downstream data. Each ONU receives only its own data — the OLT encrypts traffic with a unique key per ONU. Upstream data is inherently secure because each ONU transmits in its assigned time slot. AES encryption is enabled by default in most OLTs like our EPON/GPON models. For additional security, MAC address filtering and ONU authentication are supported.

Is Fiber Optic Cheaper Than Copper in the Long Run?

Yes. While fiber optic cabling costs 20-30% more upfront, its total cost of ownership (TCO) over 10 years is 40-60% lower than copper. Fiber supports 40Gbps+ bandwidth vs copper's 10Gbps limit, has 25+ year lifespan (copper: 5-10 years), and needs no signal repeaters for up to 40km. For ISPs, the breakeven point is typically 2-3 years. Our single-mode fiber patch cables and splitters provide reliable long-term infrastructure.

10G to 400G Ethernet Guide | Langzhi Technology

10G to 400G Ethernet Evolution: SFP+/SFP28/QSFP+/QSFP28/QSFP-DD Guide

29/04/2026 Langzhi Technology

Complete guide to Ethernet speed evolution from 10G to 400G. Covers SFP+, SFP28, QSFP+, QSFP28, QSFP-DD optical modules and cabling for each speed tier.

Ethernet Speed Evolution Overview

From 10Mbps to 400Gbps, Ethernet technology has evolved dramatically. Each speed tier uses different optical module form factors and cable types.

10G (SFP+): SR (300m OM3), LR (10km), ER (40km), ZR (80km). For enterprise access layer and server connections.

25G (SFP28): Replacing 10G for next-gen server connectivity. SR (100m), LR (10km), DAC (3-5m).

40G (QSFP+): SR4 (150m MPO), LR4 (10km LC). Data center aggregation.

100G (QSFP28): The mainstream high-speed standard. SR4 (100m), LR4 (10km), CWDM4 (2km), PSM4 (500m).

200G (QSFP56): 4x50G channels. Emerging standard.

400G (QSFP-DD/OSFP): 8x50G channels. SR8 (100m), DR4 (500m), FR4 (2km), LR8 (10km). For hyperscale data centers and AI clusters.

Network Upgrade Path

SMB: 10G access, 40G/100G backbone
Enterprise: 25G server, 100G spine-leaf
Data Center: 25G/50G server, 100G/400G spine
Telco: 100G/400G backbone transport

Langzhi Technology offers full-range SFP modules, network switches, and fiber patch cables. Visit Langzhi Technology.