An equipment for shaping transmission speed of a data traffic flow in which each protocol data unit is arranged to belong to one of at least two traffic categories, said equipment comprising control equipment (105, 106, 107) arranged to a) determine, in response to sending of a protocol data unit, whether sending of a next protocol data unit should be delayed in order to meet a condition set on the transmission speed, b) delay the sending of said next protocol data unit in response to a situation in which said next protocol data unit belongs to a first traffic category and the sending of said next protocol data unit should be delayed in order to meet the condition set on the transmission speed, c) determine whether transfer speed of protocol data units belonging to a second traffic category and constituting part of said traffic flow meets a preset condition, said transfer speed being either speed of arrival of traffic represented by the protocol data units belonging to said second traffic category or transmission speed of the traffic represented by the protocol data units belonging to said second traffic category, d) allow the sending of said next protocol data unit in response to a situation in which said next protocol data unit belongs to said second traffic category and said transfer speed meets the preset condition, even if the sending of said next protocol data unit should be delayed in order to meet the condition set on the transmission speed, and e) delay the sending of said next protocol data unit in response to a situation in which said next protocol data unit belongs to said second traffic category and the sending of said next protocol data unit should be delayed in order to meet the condition set on the transmission speed and said transfer speed does not meet said preset condition, f) allow the sending of said next protocol data unit in response to a situation in which (i) said next protocol data unit belongs to said first traffic category and (ii) there is no need to delay the sending of said next protocol data unit in order to meet the condition set on the transmission speed, and g) allow the sending of said next protocol data unit in response to a situation in which (i) said next protocol data unit belongs to said second traffic category and (ii) there is no need to delay the sending of said next protocol data unit in order to meet the condition set on the transmission speed and (ii) said transfer speed meets the preset condition, characterised in that said control equipment is arranged to: h) allow the sending of said next protocol data unit in response to a situation in which (i) said next protocol data unit belongs to said second traffic category and (ii) there is no need to delay the sending of said next protocol data unit in order to meet the condition set on the transmission speed and (ii) said transfer speed does not meet the preset condition. a) determine, in response to sending of a protocol data unit, whether sending of a next protocol data unit should be delayed in order to meet a condition set on the transmission speed, b) delay the sending of said next protocol data unit in response to a situation in which said next protocol data unit belongs to a first traffic category and the sending of said next protocol data unit should be delayed in order to meet the condition set on the transmission speed, c) determine whether transfer speed of protocol data units belonging to a second traffic category and constituting part of said traffic flow meets a preset condition, said transfer speed being either speed of arrival of traffic represented by the protocol data units belonging to said second traffic category or transmission speed of the traffic represented by the protocol data units belonging to said second traffic category, d) allow the sending of said next protocol data unit in response to a situation in which said next protocol data unit belongs to said second traffic category and said transfer speed meets the preset condition, even if the sending of said next protocol data unit should be delayed in order to meet the condition set on the transmission speed, and e) delay the sending of said next protocol data unit in response to a situation in which said next protocol data unit belongs to said second traffic category and the sending of said next protocol data unit should be delayed in order to meet the condition set on the transmission speed and said transfer speed does not meet said preset condition, f) allow the sending of said next protocol data unit in response to a situation in which (i) said next protocol data unit belongs to said first traffic category and (ii) there is no need to delay the sending of said next protocol data unit in order to meet the condition set on the transmission speed, and g) allow the sending of said next protocol data unit in response to a situation in which (i) said next protocol data unit belongs to said second traffic category and (ii) there is no need to delay the sending of said next protocol data unit in order to meet the condition set on the transmission speed and (ii) said transfer speed meets the preset condition, h) allow the sending of said next protocol data unit in response to a situation in which (i) said next protocol data unit belongs to said second traffic category and (ii) there is no need to delay the sending of said next protocol data unit in order to meet the condition set on the transmission speed and (ii) said transfer speed does not meet the preset condition.