Cisco's access solutions encompass a range of access products and services to address all facets of accessing the network. Cisco Access Gateway product connects the internal telephone system to the Public Switched Telephone Network (PSTN). Cisco Access Gateways use more complex route patterns that can contain wildcards. Cisco Access gateways can route ranges of numbers with complex restrictions and manipulate directory numbers before the Cisco CallManager passes them onto an adjacent system such as a central office or private branch exchange (PBX).