Abstract: A method checking for ambiguity the definition of channels in a channel splitting arrangement, such channels being defined by a set of rules. The method includes associating a mark with each of the rules, breaking each rule down into sub-rules so that each sub-rule has one or more operators selected only from the following Boolean operators AND, equality or negation including any number of uses of these in the same sub-rule, the parent rules being able to be expressed by combining sub-rules using OR Boolean operators, each sub-rule being associated with the mark associated with the respective parent rule.

Abstract: A method in a packet switching system for arbitrating access for incoming channels (100÷109) to an outgoing channel (120) so that each channel is constrained within a minimum bandwidth, a maximum bandwidth, and a defined inter-packed delay range by use of a transferable credit value system, including a channel value for each channel, a master value, and selecting one incoming channel (100) to be permitted to transmit a packet through the outgoing channel (120), upon a transmission from one of the incoming channels (100÷109) to the outgoing channel (120) being permitted, changing the credit for that channel and making a corresponding change in the master value. Channels are eligible to transmit packets while they have a channel value within a specified limit. Channel values are reset when the master value falls outside a specified limit.

Abstract: A packet switching system including a method for determining if a real time channel with inter-packet delay requirements can be admitted into the system is disclosed. A method and means for scheduling channels to send packets based on these inter-packet delay requirement is also presented. Variations to provide selected jitter requirements on packets are also disclosed.

Abstract: A packet switching arrangement to effect rate control of acceptance of presented packets for transmission through an outgoing channel, including calculation of an autocorrection factor which permits accurate rate control, limiting burstiness while also limiting under-utilisation.