Section: 6.2.2 Logical Channels
Content: Different kinds of data transfer services as offered by MAC. Each logical channel type is defined by what type of information is transferred. Logical channels are classified into two groups: Control Channels and Traffic Channels. Control channels are used for the transfer of control plane information only: - Broadcast Control Channel (BCCH): a downlink channel for broadcasting system control information. - Paging Control Channel (PCCH): a downlink channel that carries paging messages. - Common Control Channel (CCCH): channel for transmitting control information between UEs and network. This channel is used for UEs having no RRC connection with the network. - Dedicated Control Channel (DCCH): a point-to-point bi-directional channel that transmits dedicated control information between a UE and the network. Used by UEs having an RRC connection. Traffic channels are used for the transfer of user plane information only: - Dedicated Traffic Channel (DTCH): point-to-point channel, dedicated to one UE, for the transfer of user information. A DTCH can exist in both uplink and downlink.