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Comparison of communication links used in the published literature from 1995 to 2015.
| Communication means | Usage count | Usage percentage |
| Satellite | 20 | 28% |
| Mobile (GSMa, GPRSb, CDMAc) | 19 | 27% |
| Others (Radio, VPNd, and others) | 13 | 19% |
| ISDNe | 11 | 16% |
| Broadband | 7 | 10% |
aGSM: Global System for Mobile Communication.
bGPRS: General Packet Radio Service.
cCDMA: code division multiple access.
dVPN: Virtual Private Network.
eISDN: Integrated Services Digital Network.
