Friday 20 July 2007

Telecommunications

  • Radio
  • Telephony
  • Satellite Communications
  • Communications in insecure environments

Telecommunications

The type of telecommunications found in aid work can be divided broadly into three main categories:

a. Radio

Radio communications were previously the lifeline for relief operations in environments where there were no other options. The rise of satellite telephony – and more recently of mobile telephony – has changed this, but radio communications are still a key part of NGO communications, particularly in insecure environments. In an emergency response, radio communications are either managed by NGOs themselves or more frequently by the UN on behalf of the community. Licences for radio communications are usually issued by national governments, which may set restrictions on import and use.

  • High Frequency (or short wave) is used for medium and long range communication. HF radio waves are bounced from the lower atmosphere, so the longer range of HF is offset by its vulnerability to atmospheric conditions, which can affect both transmission and reception. HF is relatively complex to set up and maintain, and requires specialist knowledge, but its advantages include connecting to telephone networks and station-to-station calling. HF radios are usually either vehicle radios or base stations, with a range of several hundred kilometres or more; common makes are Codan and Barrett.
  • Very High Frequency has a more limited range than HF since it relies on line of sight, but is more reliable. VHF range can be increased by deployment of repeater stations at strategic locations (usually on an elevation such as a hill or a tall building), where two VHF stations are visible to the repeater but not to each other. VHF is generally used for voice communication, and requires less technical expertise than HF to set up and manage. (VHF is also used for television and FM radio broadcasting.) VHF radios are usually hand-held (typical range 2-5km), vehicle radios (up to 20km range), or base stations (up to 50km range); common makes are Motorola, Icom and Yaesu.

For concise further information, see the ECHO Generic Security Guide for Humanitarian Organisations, section 4.10 (a) and Annex 24.

b. Telephony

Telephone networks are usually run by the national government or commercial vendors under licence from the government. Recently mobile networks have been established as part of the emergency response (for example, in Kabul after the removal of the Taliban).

  • Fixed line networks are the most ‘traditional’ of communications solutions, operating over a public telephone network through metal wire or optical fibre. As well as voice communication, internet access is commonly provided through the same lines, either via a dial-up connection or on a dedicated line. Landlines are more reliable and cheaper to run than mobile communications, although they are more expensive to install and maintain.
  • Mobile (or cellular) networks have expanded massively in the last decade, in some cases enabling developing countries to avoid fixed line networks. This is partly a question of the lower cost of setting up cell networks, but also of their portability and flexibility, which includes the capacity to transmit data, not just voice. Mobile telephones transmit over electromagnetic waves through a network of fixed base stations (or ‘cells’).

c. Satellite Communications

Satellite communications have extended the reach of agency communications into the deep field, particularly as fixed and running costs have come down in the last ten years. Satellite technology develops quickly and new solutions are appearing all the time; at the time of writing, Inmarsat had just released its new BGAN services with lower costs and improved data communications.

  • Thuraya is a regional satellite service serving Europe, Africa and the Middle East, working through authorised service providers. Thuraya handsets are popular with aid agencies because they are highly portable and have a dual mode that enables them to use both the Thuraya satellite network and GSM mobile networks that have an agreement with Thuraya. Thurayas can also be used for data connectivity, although this is more complicated and costly,and bandwidth is poor.
  • Inmarsat is an international telecommunications company that provides a range of satellite communications services. At the time of writing, the most common in use by the NGO community was RBGAN. The RBGAN network is provided by Inmarsat, with various vendors making RBGAN units for the market. RBGAN units are portable, reliable and offer good voice and data connections, but are considered expensive to operate and their use is generally minimised by agencies. Inmarsat also provide the widely-used Mini-M products.
  • VSAT (Very Small Aperture Satellite) is a satellite ground station technology characterised by a relatively small satellite dish (less than 3m). There are a number of VSAT providers, generally operating on a regional basis. VSAT is increasingly used as a means of delivering broadband internet access to remote or rural locations that cannot get reliable internet access through local providers.
  • Iridium is an international company managing a global satellite network that handles voice and data communications via handheld units (provided by either Motorola or Kyocera). One of the smaller providers, they are used by some agencies particularly in the Pacific region.

Communications in Insecure Environments

There are some key points to remember about managing communications in insecure environments:

  • It is good practice, in insecure situations, for staff to have two independent means of communication (e.g. radio and satellite phone), so that if one breaks down communication will still be possible.
  • Avoid dependency on mobile phones. It is fine to use them, but in a crisis a cellular telephone system is particularly vulnerable to becoming overloaded, damaged, or simply being switched off by the provider or the government.
  • Remember that no telecommunications are fully secure. Encrypting your messages can provide some security, but not all encryption is fool-proof – and encryption can attract attention from government agencies who may wish to know what you are trying to hide.

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