{"product_id":"tp-link-tl-sm321a-b-1-25g-bidi-sfp-module-pair-10-20km-reliable-link","title":"TP-Link TL-SM321A\/B 1.25G BIDI SFP Module Pair - 10-20KM Reliable Link","description":"\u003cp\u003eIn this review of the TP-Link TL-SM321A and TL-SM321B compatible pair, the bottom line is simple: this Jeirdus SFP BIDI transceiver set is for network engineers and IT teams who need a cost-effective, tested bidirectional fiber link over a single LC connector. The reviewer found the modules deliver the expected 1.25 Gb\/s performance for up to 20 km and simplify cabling by using WDM over a single strand. Because Jeirdus validates compatibility in its lab and individually tests each unit, the primary reason to buy is dependable interoperability with TP-Link and Cisco equipment without buying original-brand modules.\u003c\/p\u003e\u003ch2\u003eKey Features\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBidirectional WDM:\u003c\/strong\u003e Uses separate TX\/RX wavelengths (TX1310nm\/RX1550nm and vice versa) so a single LC fiber carries both directions, reducing cabling.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCarrier-class compatibility:\u003c\/strong\u003e Designed to meet the coding requirements for TP-Link TL-SM321A and TL-SM321B and compatible with Cisco switches for straightforward plug-and-play.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTested quality:\u003c\/strong\u003e Each transceiver is individually tested in Jeirdus labs to ensure interoperability and reduce deployment issues.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRange and speed:\u003c\/strong\u003e Supports 1000BASE-BX and 1.25 Gb\/s operation for links up to 20 km, suitable for many campus and metro applications.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDurability and warranty:\u003c\/strong\u003e Built from 100% new materials with CE and FCC compliance and backed by a 3 year replacement plus lifetime warranty for long-term peace of mind.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eWho It's For\u003c\/h2\u003e\u003cp\u003eThe ideal buyer is an IT professional, systems integrator, or small data center manager who needs a reliable, lower-cost alternative to original-brand SFP modules for point-to-point fiber links up to 20 km. It is particularly useful when single-fiber routing or limited conduit space makes simplex LC transceivers the preferred choice.\u003c\/p\u003e\u003cp\u003eThose who should look elsewhere include users requiring higher speeds than 1.25 Gb\/s or multimode fiber transceivers for short-reach links, and buyers who must use manufacturer-branded parts for vendor-managed warranties or certified equipment lists.\u003c\/p\u003e\u003ch2\u003ePros \u0026amp; Cons\u003c\/h2\u003e\u003cp\u003e\u003cstrong\u003ePros\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eCompatible with TP-Link TL-SM321A\/B and Cisco devices, easing replacements and upgrades.\u003c\/li\u003e\n\u003cli\u003eSingle LC WDM reduces fiber infrastructure needs and simplifies installation.\u003c\/li\u003e\n\u003cli\u003eIndividually tested modules and regulatory compliance increase deployment confidence.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eCons\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\u003cli\u003eLimited to 1.25 Gb\/s operation, so not suitable where multi-gigabit links are required.\u003c\/li\u003e\u003c\/ul\u003e\u003ch2\u003eSpecifications\u003c\/h2\u003e\u003ctable\u003e\n\u003ctr\u003e\n\u003ctd\u003eForm factor\u003c\/td\u003e\n\u003ctd\u003eSFP BIDI\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eData rate\u003c\/td\u003e\n\u003ctd\u003e1.25 Gb\/s\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWavelengths\u003c\/td\u003e\n\u003ctd\u003eUp: TX1310nm\/RX1550nm, Down: TX1550nm\/RX1310nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eConnector\u003c\/td\u003e\n\u003ctd\u003eSingle LC (simplex)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReach\u003c\/td\u003e\n\u003ctd\u003eUp to 20 km\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eStandards\u003c\/td\u003e\n\u003ctd\u003e1000BASE-BX-U \/ 1000BASE-BX-D\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCompliance \u0026amp; warranty\u003c\/td\u003e\n\u003ctd\u003eCE, FCC, 3 year replacement and lifetime warranty\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\u003ch2\u003eOur Verdict\u003c\/h2\u003e\u003cp\u003eThe Jeirdus-compatible TP-Link TL-SM321A\/TL-SM321B pair is a practical, cost-conscious choice for network teams who need proven bidirectional SFP transceivers for single-fiber links up to 20 km. With lab compatibility testing, individual unit checks, and a robust warranty, it offers strong value for deployments that do not require multi-gigabit speeds.\u003c\/p\u003e\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\u003cp\u003e\u003cstrong\u003eAre these modules compatible with TP-Link switches?\u003c\/strong\u003e\u003cbr\u003eYes. Jeirdus states these SFPs are designed for TP-Link TL-SM321A and TL-SM321B and are tested for coding compatibility.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat fiber connector and wavelengths do they use?\u003c\/strong\u003e\u003cbr\u003eThey use a single LC connector and operate as a BIDI pair with 1310 nm and 1550 nm wavelengths in opposite directions.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow far will the link reach?\u003c\/strong\u003e\u003cbr\u003eThe modules support links up to 20 km at 1.25 Gb\/s under the specified standards.\u003c\/p\u003e","brand":"Jeirdus","offers":[{"title":"Default Title","offer_id":48611499573467,"sku":"B07D5F5CJY","price":38.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0724\/1043\/1707\/files\/51jXZElYNkL._AC_d56b5d7d-2918-42e9-8bc3-ac152d187bd5.jpg?v=1778425810","url":"https:\/\/gearmusthave.com\/products\/tp-link-tl-sm321a-b-1-25g-bidi-sfp-module-pair-10-20km-reliable-link","provider":"GearMustHave","version":"1.0","type":"link"}