T 0628/07 (Data rate negotiation method/GLOBALFOUNDRIES) 06-07-2010

Reasons for the Decision

1. Admissibility

1.1 The appeal complies with the provisions of Articles 106 to 108 EPC 1973 which are applicable according to J 10/07, point 1 (cf. Facts and Submissions, item IV. above). Therefore it is admissible.

2. Non-attendance at oral proceedings

2.1 The need for procedural economy requires the board to reach its decision as quickly as possible while giving the appellant a fair chance to argue its case. Oral proceedings provide an appellant with the opportunity to present its concluding comments on the outstanding issues with the aim of ensuring that the case is ready for a decision at the end of the oral proceedings (Article 15(3) RPBA).

2.2 According to Article 116(1) EPC 1973, oral proceedings shall take place either at the instance of the European Patent Office if it considers this to be expedient or at the request of any party to the proceedings. In the present case, the board considered the holding of oral proceedings to be expedient and thus issued a summons accompanied by a communication as foreseen by Article 15(1) RPBA.

2.3 The board notes that in accordance with Article 15(3) RPBA, it shall not be obliged to delay any step in the proceedings, including its decision, by reason only of the absence at the oral proceedings of any party duly summoned who may then be treated as relying on its written case.

2.4 The appellant could reasonably have expected that during the oral proceedings the board would consider the objections and issues raised in its communication, (cf. Facts and Submissions, item V. above). By not attending the oral proceedings, the appellant effectively chose not to avail of the opportunity to present its observations and counter-arguments orally but instead to rely on its written case as presented in the written statement setting out the grounds of appeal and in the letter of reply dated 1 June 2010.

2.5 The board considers that the reasons on which its decision are based do not constitute a departure from grounds or evidence previously put forward which would require that the appellant be given a further opportunity to comment.

3. Closest prior art

3.1 A home phone line network, a typical hardware-software interface for it and a method for rate negotiation are disclosed in the section of the application entitled "Background of the Invention" (cf. published application: pages 1 and 2). The technical problem set out in the description is formulated on the basis of this acknowledged background art.

3.2 According to established case law of the Boards of Appeal (see for example: T 0654/92, T 0691/94, T 0087/01, T 0730/05, T 1449/05, T 0211/06), the prior art cited and acknowledged in a patent application for the purpose of formulating the technical problem may be used as starting point for assessing novelty and inventive step (cf. in particular T 0087/01, point 5.2).

3.3 The appellant did not respond to the board's observations concerning the public availability of the HPNA 2.0 specification document submitted with the letter of 19 October 2006 (cf. Facts and Submissions, item V. above) and thus it has not been established to the board's satisfaction that this document was in the public domain at the claimed priority date. However, the inventive step argumentation submitted by the appellant in its letter of 1 June 2010 was based on the omission of a specification in the HPNA 2.0 standard as to how the PHY MSE reaches the upper level driver (cf. letter of 1 June 2010, p.1, 2nd paragraph) thereby implicitly accepting the opinion expressed in the board's communication that the background art acknowledged in the application represents the closest prior art. In view of the foregoing, the board judges that despite the absence of a specific publicly available document relating thereto this background art may be taken as the closest prior art in the present case particularly in view of the fact that the appellant has not made any attempt to resile from it.

4. Novelty

4.1 The background art acknowledged in the present application discloses a chip comprising a physical layer, a media access control and a media independent interface which receives and processes a signal containing data packets (cf. published application: page 1, second to last paragraph). This implies the preparation of frames by the media access control. The physical layer receives a frame with a payload encoding and calculates a mean square error for this frame. This mean square error is sent to the upper layer driver software (cf. application: page 2, lines 12 to 14).

4.2 Thus, a method for communicating a physical layer mean square error to upper layer device driver software with the steps of receiving a frame by the physical layer, computing a mean square error for the frame by the physical layer and sending the mean square error and the frame was known from the aforementioned closest prior art.

4.3 This prior art does not specify how the physical layer mean square error reaches the upper level driver software (cf. application: page 2, lines 22 and 23). The subject-matter of claim 1 is thus novel inasmuch as it is distinguished over the closest prior art by the specification in step (c) that the mean square error and the frame are sent to the media access control and by steps (d) and (e).

5. Inventive step

5.1 The objective technical problem underlying the claimed invention may thus be formulated as how to provide a method for communicating a physical layer mean square error to an upper layer driver software for rate negotiation (cf. application: page 2, lines 22 to 25).

5.2 D2 is primarily concerned with a method for using the unused bits of a data packet comprising a first code word to transmit various types of control information, such as queue status information or flow control information, being formatted in a second code word, from one node to another (cf. D2: column 4, lines 16 to 23). D2 further discloses that in an alternative approach, according to the practice of the prior art, each code word, i.e. the primary code word and the secondary code word, may be transmitted in a separate data packet (cf. D2: column 15, lines 49 to 53). The skilled person would understand that the data packet used in D2 corresponds to a data frame. D2 thus effectively discloses two alternative possibilities for sending information, in particular control information, from one node to another, i.e. using the same frame as the data to which the information relates (in accordance with the invention of D2) or using a separate frame for the information (in accordance with the prior art practice referred to in D2).

5.3 As the preparation of frames for transmission is generally performed by the media access control, the board judges that it lies within the routine competence of the skilled person to send the mean square error and the frame to the media access control and that it does not require the exercise of inventive skill in the given context to insert the mean square error into a second frame (i.e. the frame status frame) associated with the first frame as recited in step (d) of claim 1 and to send both frames to the upper layer device driver software as recited in step (e) of claim 1.

6. Observations re appellant's submissions

6.1 The board makes the following observations concerning the appellant's submissions contained in the letter dated 1 June 2010 arguing that the subject-matter of claim 1 involves an inventive step.

6.2 The appellant's submissions emphasise two elements of the claimed solution which are considered to be of particular significance: first, the choice of the media access control as the module that prepares the mean square error to be sent to the upper layer software in the computer and second, use of the frame status frame generated by the media access control as the vehicle to carry the mean square error.

6.3 Concerning the choice of the media access control, the appellant states that there are also other possible ways to send the mean square error from the physical layer to upper level software, e.g. generating the frame status frame by the physical layer itself, but that media access control has been chosen "probably for certain technical considerations". However, these technical considerations are not explained beyond some speculative comments at the end of the paragraph bridging pages 1 and 2 of the letter.

In view of the fact that the technical considerations motivating the choice of the media access control are neither disclosed nor derivable from the application as filed nor elucidated in a satisfactory manner in the appellant's submissions, the board cannot identify any basis for concluding that the choice of the media access control as the module that prepares the mean square error to be sent to the upper layer software represents more than a straightforward, obvious design choice in the given context.

6.4 Concerning the "frame status frame", the board notes that neither claim 1 nor the description specifies this feature beyond indicating that it is a frame associated with the data frame received by the physical layer. As the manner in which the two frames are "associated" is not further defined in technical terms, the board understands this specification merely to imply that the former frame (i.e. the "frame status frame") contains status information relating to the latter frame (i.e. the data frame received by the physical layer). On this basis, the term "frame status frame" as used in claim 1 is not found to imply any particular characteristics of said frame which would distinguish it in technical terms from a conventional frame used for transporting data.

6.5 The appellant additionally submits that the intended goal of D2 is to use the unused capacity of a data frame of defined size and that the skilled person trying to modify the closest prior art in the light of D2 would thus attempt to insert the mean square error of a data frame into the frame itself rather than into a separate frame, i.e. the frame status frame. The appellant further argues that from a technical point of view such an attempt would be against the "mandate of HPNA" and, moreover, that in the context of HPNA it would be technically impossible to piggyback the mean square error into the data frame because there is not enough space.

The board notes that the appellant's argumentation in this regard relies on technical considerations that are neither disclosed nor clearly and unambiguously derivable from the application as filed which contains no identifiable mention of or reference to the aforementioned design constraints of the HPNA specification and their technical implications for the solution of the underlying technical problem.

In the absence of any identifiable technical teaching in relation to these matters in the application as filed, the board takes the view that if, as argued by the appellant, the design constraints of the HPNA specification imply that it would be both undesirable and technically impossible to piggyback the mean square error into the data frame the skilled person could be expected to recognise this without the exercise of inventive skill.

Thus, in the context of a system based on the HPNA specification, the skilled person recognising the undesirability and technical impossibility of using the piggyback approach disclosed in D2 in view of the aforementioned design constraints would be led to follow the alternative approach of the prior art of D2 according to which control information is transmitted in a separate data packet (frame). In the light of the overall disclosure of D2, the use of a separate frame for transmitting control information represents a known design alternative to the piggyback approach and one which the skilled person confronted with the stated technical problem would choose without the exercise of inventive skill in the given circumstances.

6.6 The appellant's submissions contained in the letter of reply dated 1 June 2010 have thus failed to convince the board of the inventive merits of the claimed subject-matter.

7. In view of the foregoing, the board finds that the subject-matter of claim 1 does not involve an inventive step. A corresponding objection applies mutatis mutandis to the subject-matter of the further independent claim 5. The appellant's request is therefore not allowable and in the absence of an allowable request the appeal must be dismissed.