les: implement ultralight client (#16904)

For more information about this light client mode, read
https://hackmd.io/s/HJy7jjZpm

1 files changed, 9 insertions, 0 deletions

diff --git a/eth/ulc_config.go b/eth/ulc_config.go
new file mode 100644
index 000000000..effa6da21
--- /dev/null
+++ b/eth/ulc_config.go
@@ -0,0 +1,9 @@
+package eth
+
+const DefaultULCMinTrustedFraction = 75
+
+// ULCConfig is a Ultra Light client options.
+type ULCConfig struct {
+	TrustedServers     []string `toml:",omitempty"` // A list of trusted servers
+	MinTrustedFraction int      `toml:",omitempty"` // Minimum percentage of connected trusted servers to validate trusted (1-100)
+}