In ATM, a mechanism is needed for the establishment and release of VPCs and VCCs. The exchange of information involved in this process is referred to as control signaling and takes place on separate connections from those that are being managed.

For VCCs, I.150 specifies four methods for providing an establishment/release facility. One or a combination of these methods will be used in any particular network:

1. Semipermanent VCCs may be used for user-to-user exchange. In this case, no control signaling is required.
2. If there is no preestablished call control signaling channel, then one must be set up. For that purpose, a control signaling exchange must take place between the user and the network on some channel. Hence we need a permanent channel, probably of low data rate, that can be used to set up VCCs that can be used for call control. Such a channel is called a meta-signaling channel, as the channel is used to set up signaling channels.
3. The meta-signaling channel can be used to set up a VCC between the user and the network for call control signaling. This user-to-network signaling virtual channel can then be used to set up VCCs to carry user data.
4. The meta-signaling channel can also be used to set up a user-to-user signaling virtual channel. Such a channel must be set up within a preestablished VPC. It can then be used to allow the two end users, without network intervention, to establish and release user-to-user VCCs to carry user data.

For VPCs, three methods are defined in I.150:

1. A VPC can be established on a semipermanent basis by prior agreement. In this case, no control signaling is required.
2. VPC establishment/release may be customer controlled. In this case, the customer uses a signaling VCC to request the VPC from the network.
3. VPC establishment/release may be network controlled. In this case, the network establishes a VPC for its own convenience. The path may be network-tonetwork, user-to-network, or user-to-user.