Nokia Siemens Networks has agreed to sell its Optical Networks business to Marlin Equity Partners, the private equity firm that recently announced plans to buy what was left of Sycamore Networks Inc.

No financial terms were disclosed. Once the deal is concluded, which is expected to happen in early 2013, about 1,900 NSN staff, most of whom are based in China, Germany and Portugal, will transfer to Marlin. The private equity firm is creating a new optical systems company, based in Munich, with NSN's current head of optical, Herbert Merz, as the CEO.

The divestment includes NSN's 100Gbit/s coherent platform, the hiT 7300, and its packet-optical switch, the hiT 7100, plus a number of network management and planning tools. NSN claims to have more than 200 optical transport systems customers. (See XO Deploys First Nationwide 100G Network, XO's Not Done Yet With 100G, NSN Makes Optical Advances and Euronews: NSN Lands 100G Deal.)

The deal does not include NSN's Carrier Ethernet assets, for which a separate divestment deal is being sought. (See Can NSN Offload Its Carrier Ethernet Assets?)

NSN has already sold a number of technology assets, including its microwave backhaul, WiMax, fixed access broadband and IPTV product lines, and is still seeking buyers for others parts of the business. (See Is NSN Close to BSS Sale? and M&A Interest in NSN's BSS Assets Builds.)

Marlin intends to form a new optical equipment company around the new acquisition and buy more assets: It says it "intends to act as a consolidator, building an industry leader in the fragmented optical networking sector."

That sector, which generates sales of around US$15 billion a year currently, has been in decline this year, according to Ovum Ltd. . The current market leaders, according to Infonetics Research Inc. , are Huawei Technologies Co. Ltd. , Ciena Corp. (Nasdaq: CIEN) and Alcatel-Lucent (NYSE: ALU). (See Ovum: Optical Networking Market Shrinks Again.)

Lightreading