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An access network is a section of telecommunications network which connects end users to their immediate service provider. It is contrasted with the core network, which connects local providers to one another. The access network may be further divided between feeder plant or distribution network, and drop plant or edge network.^{[further explanation needed]}

An access network refers to the series of wires, cables and equipment lying between a consumer/business telephone termination point (the point at which a telephone connection reaches the customer) and an outside plant or telephone exchange, and between outside plants which can connect each other, feed into exchanges, and serve as repeaters. Older access network infrastructure consists largely of coaxial cabling or twisted pairs of copper or aluminum wires emplaced for telephone communications. The exchanges, formerly staffed by switchboard operators, now often contain banks of automated switching equipment which direct a call or connection to the end user.

With the advent of the World Wide Web and the internet, telecommunications providers started offering internet services across existing access network infrastructure. The introduction and rapid increase in popularity of wireless cellphones^[1] caused telecommunications companies to rely more on internet services such as DSL, VoIP, and Internet Protocol television as revenue from Plain Old Telephone services decreased.

As technology has advanced, there have been multiple attempts to improve the effectiveness and longevity of existing infrastructure. Switching data transmission from analog to digital allows for faster data and more efficient multiplexing of multiple data streams to increase bandwidth capacity. Companies may also replace the aluminum wiring utilized in some networks, as it may present issues caused by electromigration.This results in increased electrical resistance, reducing signal integrity and ultimately leading to the complete failure of the wire. As existing networks age, telecommunications companies are beginning to replace traditional wired networks entirely and move towards optical fiber networks, which can support much higher bandwidths, cost less, and have intrinsically better security.^[2] As of June 2023, approximately 55% of US households are within range of a fiber internet access network, and approximately 12.5% of US households have an active fiber optic internet connection.^[3]

The process of communicating with a network begins with an access attempt, in which one or more users interact with a communications system to enable initiation of user information transfer. An access attempt itself begins with issuance of an access request by an access originator.

An access attempt ends either in successful access or in access failure – an unsuccessful access that results in termination of the attempt in any manner other than initiation of user information transfer between the intended source and destination (sink) within the specified maximum access time.

Access time is the time delay or latency between a requested access attempt and successful access being completed. In a telecommunications system, access time values are measured only on access attempts that result in successful access.

Access failure can be the result of access outage, user blocking, incorrect access, or access denial. Access denial (system blocking) can include:

• Access failure caused by the issuing of a system blocking signal by a communications system that does not have a camp-on busy signal feature.
• Access failure caused by exceeding the maximum access time and nominal system access time fraction during an access attempt.

An access charge is a charge made by a local exchange carrier for use of its local exchange facilities for a purpose such as the origination or termination of network traffic that is carried to or from a distant exchange by an interexchange carrier.

Although some access charges are billed directly to interexchange carriers, a significant percentage of all access charges are paid by the local end users.

• GERAN
• UTRAN
• E-UTRAN
• CDMA2000
• GSM
• UMTS
• 1xEVDO
• voLTE
• Wi-Fi in* WiMAX

A passive optical distribution network (PON) uses single-mode optical fiber in the outside plant, optical splitters and optical distribution frames, duplexed so that both upstream and downstream signals share the same fiber on separate wavelengths. Faster PON standards generally support a higher split ratio of users per PON, but may also use reach extenders/amplifiers where extra coverage is needed. Optical splitters creating a point to multipoint topology are also the same technology regardless of the type of PON system, making any PON network upgradable by changing the optical network terminals (ONT) and optical line terminal (OLT) terminals at each end, with minimal change to the physical network.^[4]

Access networks usually also must support point-to-point technologies such as Ethernet, which bypasses any outside plant splitter to achieve a dedicated link to the telephone exchange. Some PON networks use a “home run” topology where roadside cabinets only contain patch panels so that all splitters are located centrally. While a 20% higher capital cost could be expected, home run networks may encourage a more competitive wholesale market since providers’ equipment can achieve higher use.^[5]

• Edge device
• Hierarchical internetworking model
• Internet access
• IP connectivity access network
• Local loop
• Passive Optical Network

• “The Network Story”. British Telecom. 2005. Archived from the original on May 5, 2010. Interactive presentation introducing the technology and design of access networks