Bolstering Peers
Secure, irreversible economic freedom is vital because it represents a basic foundation and stepping stone to more comprehensive independence. Not only can financial sovereignty give a passive avenue to resist a government encroaching on personal freedom, but it can also give individuals the opportunity to do the same within a domestic setting.
Satellite coverage is an essential first step in ensuring sound, consistent and borderless dispersal of Bitcoin participation. The utility provided by having constant access to bitcoin blocks, with only a fifty dollar dish, to a permissionless, off-grid payment rail is immense.
The provision of free satellites and API's for data download are undoubtedly valuable for providing constant access to Bitcoin while also dramatically decreasing the cost of running a node. Still, looking through a critical lens surmises some reasonable vulnerabilities that will hopefully be addressed by the greater Bitcoin community going forward. Just because satellites largely represent a "last resort", does not mean it should be reliant on a lesser security model than would otherwise be acceptable.
Blockstream is currently renting hosted space on a variety of satellites spread orbiting the world. Because the satellites are not built for Blockstream, they act as relay devices instead of full nodes, broadcasting blocks uplinked from ground stations to the other satellites as well and receiver dishes throughout the world. With a dedicated satellite, Blockstream wouldn't have to use ground stations but the financial burden of this is significant.
In the next few years, the world may see rural, low-bandwidth areas in underdeveloped regions integrate Bitcoin into the local economy by way of receiving free blocks from mounted dishes, and then verifying and proliferating around the blocks around a local mesh net. These economies may be solely reliant on blocks broadcasted by their regional satellite for connectivity to the main chain. This means the local economy hinges on the validity and consistency of data being uplinked from ground stations. Without access to the internet or other satellites, on a whim, an economy can be partitioned from the network via an overreliance on a single peer. While nobody could force individual nodes to accept blocks based off of non-consensus rules, an eclipse attack remains a pronounced threat.
CubeSats
CubeSats differ from larger, more permanent and powerful satellites and could give the Bitcoin network additional security and fault tolerance. First, CubeSats are customizable enough to run individual validating full nodes from space. This means low bandwidth users without internet connectivity could broadcast and receive blocks from a network of peers in space rather than a single satellite. With a fleet of dedicated CubeSats, no ground stations or teleports are needed.
CubeSats are relatively inexpensive and are often released into Low Earth Orbit (LEO) as secondary cargo. For power, CubeSats rely on a combination of solar panels and built-in battery. While they are inexpensive, they can also be unreliable and often fall out of Orbit in only a few months. Bitcoin Developer Jeff Garzik considered launching his own fleet of CubeSats but plans seem to have sputtered.
the #bitcoin satellite network is using leased bandwidth on 4 geostationary sats over 6 coverage zones. they are mixed use broadcasting TV & industrial data etc. problem with cubesats is you either need lots of them, or tracking dishes. also need BIG dishes because signal is weak— Adam Back (@adam3us) December 18, 2018
While CubeSats can provide more peers than a larger constellation, they can't necessarily provide as consistent of peers. CubeSats sit in LEO and are knocked down and around by atmospheric conditions, requiring constant recalibration. Problems with this can be mitigated through being in the range of many nodes or with a tracking dish. But even then, the low power of these devices can make connectivity a challenge due to bandwidth constraints.
This is addressed in a new Bitcoin proposal dubbed "Minisketch" focussed on dramatically reducing the bandwidth overhead associated with running a Bitcoin full node by cutting down on the amount of redundant data being broadcasted. Satellites are listed as one of the top applications in the Github seen below.
Geostationary CubeSats?
CubeSats are improving rapidly and becoming cheaper as they reach economies of scale. If they were able to provide the same consistency as larger Geostationary Satellites, CubeSats could provide more reachable network peers for off-grid users and thus more decentralization and security. Instead of an off-the-grid town being tolerant to only the failure of one regional satellite, they could now connect to a series of local ones as well, adding malevolent CubeSats to Jameson Lopp's dedicated bad node list.
CubeSats are launched into orbit with a solar panel and battery, but if the device ever turns energy negative, it immediately becomes space debris. The battery needs to be strong enough to constantly last through periods of zero sunlight.
Securing New Value
Bolstering security is necessary as new protocols begin to bootstrap bitcoin's security model for securing more than just transactions.
Microsofts "sidetree", an open-source permissionless digital identity protocol, plans on pinning user-owned digital identity to bitcoin transactions and transacting public-key, distributed identifiers through HTLC channels and around a dedicated sidechain mesh. Once again, this directly affects off-grid users who often lack a sound, secure, or accessible form of identification. Low-cost proof of identity can help give people access to financial services and can even be incorporated into existing government functions.
Another sidechain, Lot49, is being developed to incentivize a mesh-net for communication over GNU radio. As this project expands, communication networks can be built by running Lot49 with local peers and settling on the global Bitcoin chain for payment finality by broadcasting to a fully validating CubeSat. Lot49 mesh will support applications like point of sale, without an internet connection.
The additional value relying on the Bitcoin network should be factored in when considering how Bitcoin's security model will adapt over time. The proliferation of a more robust satellite network including an fleet of fully validating CubeSat nodes would have a tremendous impact on both ease of participation and overall security. If the proposal for Minisketch is incorporated into Bitcoin, it would have a sizeable impact on the viability of CubeSats and protect low-bandwidth users from eclipse attacks.
written by Francis
