# Network Media ### Three Media Types Modern networks use three types of media to interconnect devices: * Metal Wires within Cables : data is encoded in electrical impulses * Glass or Plastic Fibers within Cables : data is encoded into pulses of light * Wireless Transmission : data encoded via modulation of frequencies of electromagnetic waves The primary criteria for choosing a network media are: * What is the max distance the media can successfully carry a signal? * What is the environment the media will be installed in? * What is the amount of data and what speed must it be transmitted? * What is the cost of the media? The three most common types of network cable are: * Twisted Pair : wires are grouped in pairs and twisted to reduce interference, the pairs of wires are coloured so you can identify them at both ends. Typically one wire is solid colour and its partner is the same colour but with a white stripe. * Coaxial Cable : copper cable used by cable TV companies, also used for connecting various components which make up satellite communication systems. This cable has a single rigid copper core which conducts the signal, the core is typically surrounded by insulation, metal shielding and a protective jacket. * Fiber-Optic Cable : can be either glass or plastic, unaffected by electrical interference. Also used in medical imaging, medical treatment and mechanical engineering inspection. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://contrxl.gitbook.io/contrxl/systems-administration/cisco/networking-basics/network-media.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.