By Darren Waters
Technology editor, BBC News website
When natural disaster or war strikes a country the first priorities for victims are typically food, water and shelter.
The satellite equipment is portable and can be running in minutes
But communications are essential too. After the Asian Tsunami in 2004, telephone landlines, mobile phone networks and internet connections were wiped out.
For effective relief to be brought to the affected areas humanitarian agencies need to co-ordinate their efforts and victims need to contact loved ones.
The conflict in southern Lebanon has left much of the region without any communications infrastructure and one agency, Telecoms Sans Frontieres (TSF), is working to put people back in touch with one another.
Julie Cazenave, TSF's delegate for the Americas who is in Lebanon, said: "Everything in south Lebanon has been destroyed by the bombs up to 20 kilometres from the border.
"They don't have electricity, they don't have phones, landlines or cellphones, they don't have water.
"It's a difficult situation."
MAP OF TELECOMS IN LEBANON
Source: Telecoms Sans Frontieres
TSF is a non-governmental organisation (NGO) funded by corporate partners such as satellite firm Inmarsat, mobile firm Vodafone and the European Commission.
The body is called into disaster areas by the United Nations when communications for a region or country are put out of action. But TSF can also act of its own accord.
Oisin Walton, TSF's communications director, said: "We would deploy within 24 hours of a call for up to 30 days of the disaster."
TSF has two prongs of its response - to set up telecoms for relief agencies and NGOs and to provide victims of disaster and war a chance to phone loved ones.
Mr Walton said: "We deploy a telecoms centre with internet facilities - access to e-mail, phone and fax and IT support for NGOs.
"We also help users set up their computers and with connecting to the internet."
Quickly set up
TSF has 13 full-time employees and 40 volunteers spread over three bases in France, Nicaragua and Thailand.
The organisation takes mini-satellite phones and
portable satellite broadband and phone devices, called BGAN, into areas to quickly set up a communications network.
"We can get services set up within minutes," said Mr Walton.
He said: "TSF started with one satellite phone in 1998 and now we have approximately 50 sat lines today. We have 30 data transmitters."
Phone lines and mobile antennas were destroyed in south Lebanon
In Lebanon TSF is working in areas such as Tyre and Sidon.
Ms Cazenave said: "We have sent two teams. One left on 7 August and we have been sent as the second team to give support.
"When I arrived the first team had set up internet connections and was giving IT support to NGOs and UN in different places."
Based on an assessment of need, Ms Cazenave said TSF had been travelling from village to village giving people the chance to get in touch with family for the first time since bombs had destroyed phone lines and mobile antennas.
"It's fantastic. You can see the result of your work in the moment. You give the phone and see people talk to their families - they are smiling and crying. "
TSF aims to stay for 30 days in an area following its arrival and after that time the United Nations will typically bring in its own satellite communications or potentially the area's own infrastructure is back up and running.
"When we leave everybody needs to be autonomous," said Mr Walton.
"Satellite solutions like BGAN are very reliable and efficient and can be deployed within minutes - but it's expensive. It's not a long term solution," he added.
Are you living in south Lebanon? Have you been able to contact friends and family? How badly damaged were communications in your region?
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