Editing Secure communication (section)

== Systems offering partial security ==

=== Cellphones ===
Cellphones can easily be obtained, but are also easily traced and "tapped". There is no (or only limited) encryption, the phones are traceable – often even when switched off{{Citation needed|date=August 2009}} – since the phone and SIM card broadcast their International Mobile Subscriber Identity ([[International mobile subscriber identity|IMSI]]). It is possible for a cellphone company to turn on some cellphones when the user is unaware and use the microphone to listen in on you, and according to James Atkinson, a [[counter-surveillance]] specialist cited in the same source, "Security-conscious corporate executives routinely remove the batteries from their cell phones" since many phones' software can be used "as-is", or modified, to enable transmission without user awareness and the user can be located within a small distance using signal [[triangulation]] and now using built in GPS features for newer models. Transceivers may also be defeated by [[Radio jamming|jamming]] or [[Faraday cage]].

Some cellphones ([[Apple Inc.|Apple]]'s [[iPhone]], [[Google]]'s [[Android (operating system)|Android]]) track and store users' position information, so that movements for months or years can be determined by examining the phone.<ref>[https://online.wsj.com/community/groups/question-day-229/topics/how-concerned-you-iphone-tracks?commentid=2388220 Wall Street Journal: How concerned are you that the iPhone tracks and stores your location?]</ref>

The U.S. Government also has access to cellphone surveillance technologies, mostly applied for law enforcement.<ref>Pell, Stephanie K., and Christopher Soghoian. 2014. "Your secret stingray's no secret anymore: The vanishing government monopoly over cell phone surveillance and its impact on national security and consumer privacy." ''Harv. JL & Tech'' 28(1).</ref>

=== Landlines ===
Analogue landlines are not encrypted, it lends itself to being easily tapped. Such tapping requires physical access to the line which can be easily obtained from a number of places, e.g. the phone location, distribution points, cabinets and the exchange itself. Tapping a landline in this way can enable an attacker to make calls which appear to originate from the tapped line.

=== Anonymous Internet ===
{{Main|Anonymity}}
Using a [[wikt:third-party|third party]] system of any kind (payphone, Internet cafe) is often secure, however if that system is used to access known locations (a known email account or 3rd party) then it may be tapped at the far end, or noted, and this will remove any security benefit obtained. Some countries also impose mandatory registration of Internet cafe users.

[[anonymous proxy|Anonymous proxies]] are another common type of protection, which allow one to access the net via a third party (often in a different country) and make tracing difficult. Note that there is seldom any guarantee that the [[plaintext]] is not tappable, nor that the proxy does not keep its own records of users or entire dialogs. As a result, anonymous proxies are a generally useful tool but may not be as secure as other systems whose security can be better assured. Their most common use is to prevent a record of the originating [[IP address|IP]], or address, being left on the target site's own records. Typical anonymous proxies are found at both regular websites such as Anonymizer.com and spynot.com, and on proxy sites which maintain up to date lists of large numbers of temporary proxies in operation.

A recent development on this theme arises when wireless Internet connections ("[[Wi-Fi]]") are left in their unsecured state. The effect of this is that any person in range of the base unit can [[piggybacking (Internet access)|piggyback]] the connection – that is, use it without the owner being aware. Since many connections are left open in this manner, situations where piggybacking might arise (willful or unaware) have successfully led to a defense in some cases, since it makes it difficult to prove the owner of the connection was the downloader, or had knowledge of the use to which unknown others might be putting their connection. An example of this was the Tammie Marson case, where neighbours and anyone else might have been the culprit in the sharing of copyright files.<ref>[https://www.theregister.co.uk/2007/04/25/open_wi-fi_child_porn_case/ Open Wi-Fi proves no defence in child porn case], The Register</ref> Conversely, in other cases, people deliberately seek out businesses and households with unsecured connections, for illicit and anonymous Internet usage, or simply to obtain free [[Bandwidth (computing)|bandwidth]].<ref>[https://www.theregister.co.uk/2007/12/11/piggybacking_arrest_made/ 'Extortionist' turns Wi-Fi thief to cover tracks], The Register</ref>

=== Programs offering more security ===
{{see also|Comparison of instant messaging clients#Secure messengers|Comparison of VoIP software#Secure VoIP software}}
* [[Secure instant messaging]] – Some instant messaging clients use [[end-to-end encryption]] with [[forward secrecy]] to secure all instant messages to other users of the same software. Some instant messaging clients also offer end-to-end encrypted file transfer support and group messaging. 
* [[VoIP]] – Some VoIP clients implement [[ZRTP]] and [[Secure Real-time Transport Protocol|SRTP]] encryption for calls.
* [[Secure email]] – some email networks are designed to provide encrypted and/or anonymous communication. They authenticate and encrypt on the users own computer, to prevent transmission of plain text, and mask the sender and recipient. [[Mixminion]] and [[I2P#I2P-Bote|I2P-Bote]] provide a higher level of anonymity by using a network of anonymizing intermediaries, similar to how [[Tor (anonymity network)|Tor]] works, but at a higher latency.
* [[IRC]] and web chat – Some IRC clients and systems use client-to-server encryption such as [[Secure Sockets Layer|SSL]]/[[Transport Layer Security|TLS]]. This is not standardized.