Lightning Strikes Stellar

First Bitcoin (BTC), then Litecoin (LTC), then….Stellar (XLM)? Developers for the sixth-largest cryptocurrency have revealed the first rungs of a second-layer payments system, potentially opening the door to an instantaneous off-chain settlement with no fees. In a Medium post, Interstellar revealed the first testate demo for “Starlight,” a Lightning Network for the Stellar Lumens cryptocurrency.  The move puts Stellar in the footsteps of Bitcoin and Litecoin, which have also explored off-chain payments as redemption for their longer block times and growing fees. Instead of paying fees for multiple payments, participants using off-chain payment rails can escrow their funds in a multi-signature wallet, allowing many bi-directional transactions for only a single set of fees.   “Normally, making a payment on a network like Stellar involves publishing details of the payment to all observers, paying a small fee, and waiting for the network to reach consensus and confirm the payment,” wrote Interstellar’s Dan Robinson, in the post. “A payment channel, on the other hand, uses the network to ‘lock up’ some funds for use by the channel’s participants. They may then pay each other these funds without further involving the network. Such payments are thus private, instant, and free.” As Crypto Briefing has previously reported, the system gets more complicated when there are more than two participants involved. Multi-hop payments have proven to be the Achilles’ heel of the Lightning Network, causing long delays and unexpected complications.  At present, Starlight is only designed for two-party settlement, but the blog post indicates that this may merely the first step. “As we extend the Starlight project to support not only payment channels but also multi-hop payments across those channels,” Robinson wrote, “we plan to build in compatibility with other payment-channel networks, such as Lightning and [Ripple’s] Interledger.” Starlight, Star-Bright Future? Day-to-day payments are not likely to find large advantages from off-chain payments, considering that Stellar fees are already about ten times cheaper than Litecoin transactions, with settlement times measured in seconds.    Above: Average fees for Bitcoin (red) Litecoin (gray) and Stellar (orange). Via coinmetrics.io  However, a reliable system of off-chain payments would raise the possibility of new kinds of transactions. In particular, it enables micro-payments at a sub-cent level, something which is not practical in the wildest dreams of the legacy payments system.  We’ve already seen some ersatz applications for the Lightning Network in Bitcoin, like the homemade vending machine that allows users to pay for soda by the milliliter. There are also applications that involve paying for music by the second, incremental mobile top-ups, paid content, and paying for storage through services like FileBazaar.  However, it’s too early to get excited for Starlight—the testnet-only demo is not yet practical, even for limited use, and developers warn users to expect bugs and incompatible updates. Those cautions probably won’t stop lumenauts from dreaming of a future where payments move at the speed of—well, you know.    The author has investments in Stellar and Bitcoin.