The adverts, which likely cost several hundred thousand dollars, are an attempt to calm nervous customers and prevent Cisco Systems Inc from using the acquisition as an opportunity to poach business, mostly from McData. According to sources, Cisco has already told its sales force and channel partners to campaign on the idea that the Brocade-McData merger will cause problems for customers.

But among the list of pledges made by Brocade are that it will not abandon McData’s directors or FICON support at least until it has developed a converged post-merger replacement, and that even before then it will develop some form of native interoperability between it and Brocade’s gear, and that it will not end-of-life any products without giving its OEM customers at least six months’ notice.

We’ve been getting two, or three calls a day from customers mostly from McData customers, said Brocade’s VP of product development Don Jaworski.

Brocade and McData have heavily overlapping product sets, so a post-merger product cull is inevitable. But because interoperability between any SAN switches or directors made by different vendors is usually limited, McData’s customers will be worried that they will not be able to simply slot Brocade gear in place of existing McData gear.

Brocade told Computer Business Review, however, that it will develop microcode that can be loaded onto Brocade and McData gear to reverse that situation, by providing interoperability between the two sets of products. This will be more than just the limited or dumb interoperability mode that is already available. The goal is to deliver fully functional, native interoperability, Brocade said.

Under US law, Brocade and McData must currently continue business as usual, and this means that the two rivals’ engineering teams cannot yet meet to determine the exact degree of interoperability. There may be some limitations, but the goal is native interoperability, said Jaworski. This interoperability will extend to the future converged director, he said.

Some of the other promises made by Brocade in its advert are that it will publicize detailed product plans after the merger, and that it will continue to repair FRUs for five years after the last shipment of any product.

The first appearance of the advert yesterday co-incided with a conference held by Brocade for financial analysts in New York City. Brocade not only has to placate customers, but also Wall Street, which has not universally approved of the merger with McData.

The advert ran in the North American edition of the WSJ yesterday, and was set to run in the WSJ’s European and Asian editions later this week, and at an unspecified date in Business Week. By press time yesterday evening, it had not been posted on Brocade’s or McData’s web sites.