Ciena Corp. (NYSE: CIEN) further cemented its 21CN relationship with BT Group plc (NYSE: BT; London: BTA) today by announcing a deal to supply the British carrier with Ethernet access gear from its OEM partner ANDA Networks Inc.

Ciena has been a preferred vendor for the British incumbent's £10 billion next-generation network project from the beginning as one of two optical transport equipment suppliers. (See Vendors Sign BT 21CN Contracts, BT Unveils 21CN Suppliers, and Ciena Touts BT Deployment.)

Now it's extending that relationship by landing a contract to provide its CN 3000 Ethernet Access solution – ANDA hardware and Ciena management software – for the delivery of Ethernet services to business and wholesale customers.

ANDA specializes in Ethernet access equipment that's deployed at the edge of a carrier's network and at end-user premises. (See ANDA Unveils EtherReach 1000, ANDA Introduces EtherSLAM, ANDA Extends EtherReach, and Anda Unveils Ethernet Aggregator.)

No commercial terms were announced.

A key element of the new BT deal appears to be ANDA's support for Provider Backbone Transport (PBT) (also known as PBB-TE), the controversial new flavor of carrier Ethernet that is attracting growing support in the vendor community. (See PBT Stars at Ethernet Expo , Ciena's PBB-TE Play, and PBT: New Kid on the Metro Block.)

BT is PBT's leading carrier supporter and is deploying the technology as part of its 21CN Ethernet equipment rollout. (See BT Goes Live With PBT and BT Pressures Vendors Over PBT.)

Ciena isn't the only company supplying Ethernet access gear for 21CN, though. In February this year ADVA Optical Networking landed a similar deal and in September said it had already deployed more than 100,000 Ethernet ports in the British incumbent's network. (See ADVA Lands 21CN Deal and ADVA Touts BT Deployment.)

News of Ciena's new 21CN engagement came as the vendor announced fourth-quarter earnings that exceeded analyst expectations.

— Ray Le Maistre, International News Editor, Light Reading