Jameson Loeb, co-founder and CTO of Casa, a crypto archive company, posted a report on the performance test of multi-signature bitcoin hardware signing on the Casa blog on September 13th.

The results show that hardware encrypted wallets can handle small and simple transactions well. However, they have trouble completing when the transaction becomes complex. Casa is said to be built on geographically dispersed hardware with multiple signatures, hardware designed to lock keys, customized user interface and customer service.

Loeb noted that although the company does not control the hardware, the goal is to keep any device alive at the end of the day. Therefore, he decided to do some research and hoped to draw some conclusions and help software vendors with multiple signatures better understand hardware limitations and customize wallet software for better performance.

Casa is currently compatible with six devices, including Trezor, Ledger, Coinkite and Coldcard. Testing was performed on all supported devices and BitBox.

Re-tested using the Electrum 4.0.2 implementation on Debian Linux and created many P2WSH (original segwit) wallets that use Bitcoin test networks and USB-connected devices. 100 UTXOs were deposited in each wallet.

Lopp created a series of tests to determine the properties of this hardware box when signing transactions with multiple signatures of varying complexity. Repeat these tests and conclude that it is better and safer for devices to display download and signature progress bars. He added:

“I really hate devices that do not show downloads and sign progress lines. In this regard, I prefer Coldcard and Trezor. Both BitBox and Ledger are disturbing because you have no idea what’s really going on. ”

When it comes to getting around transaction size restrictions and processing time delays, Lopp suggested that hardware wallets try to split the transfer into several smaller transactions that do not reach the limits.

When the transaction process takes a long time, some devices disconnect due to inactivity. Race suggests that the least a device manufacturer can do to avoid such inconveniences is to disable screen lock timeouts while the device is still running in a transaction.

The hardware must also support partially signed Bitcoin (PSBT) transactions and all possible valid multi-signature transactions, said Lopp. He added:

“I think it’s time for device manufacturers to start working as platform vendors and make sure they offer reliable platforms that can be used to build different solutions.”

When signing a Bitcoin transaction, the devices must complete two steps, said Flea:

First, the transaction is downloaded to the device, and you analyze the details and display them on the user confirmation screen. These details usually represent the address (es) to which the money is sent, the amount (s) being sent, and the fees paid. Then, after user confirmation, the device signs each transaction record and then returns the signed transaction to the wallet application.

Source: CoinTelegraph