(C) POPs
Reason:
Wireless Interconnection to the Public Switched Telephone Network
Interconnection is defined as the point where any two (carriers') networks are linked together. It can involve a wireless carrier's connection to a local exchange carrier (LFQ a landline telco), or an Internet service provider's (ISP's) connection to an LEC, or an LEC's connection into an interexchange carrier (IXC).
Approximately 75% of all cellular telephone calls made today are initiated from mobile/portable phones, with the destination being a landline telephone. This number has been slowly but steadily changing to the point where more traffic is being terminated on wireless carriers' phones. These types of calls are known in the wireless industry as mobile-originated, or mobile-to-land (M-L) telephone calls. This large volume of mobile-land wireless traffic, it is imperative that a wireless carrier develops and maintains a cost-effective series of interconnections to the public switched telephone network (PSTN). The public switched telephone network is that which we use every day to place our telephone calls, whether they are across town, cross-country or across the world. In its most basic form, the PSTN is accessed every time a person picks up a telephone and hears a dial tone.
To develop the interconnections, a wireless carrier must first examine where to place interconnections and what type of interconnections should be ordered. This decision can be based on several factors.
First, a logical location for connection to the public telephone network is to place an interconnection, also known as a point of presence (POP).
Second, cost factors must be taken into account to justify the placement of an interconnection.
Third, the population density of a given geographic region must be examined to determine whether a local interconnection will suffice or whether a connection that offers low cost-per-minute charges over a wider area is more appropriate.
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