diff --git a/cmd/geth/config.go b/cmd/geth/config.go
index 27490c4048..bc5d54b30a 100644
--- a/cmd/geth/config.go
+++ b/cmd/geth/config.go
@@ -126,6 +126,7 @@ func makeConfigNode(ctx *cli.Context) (*node.Node, gethConfig) {
 	}
 
 	// Apply flags.
+	utils.SetULC(ctx, &cfg.Eth, &cfg.Node.P2P)
 	utils.SetNodeConfig(ctx, &cfg.Node)
 	stack, err := node.New(&cfg.Node)
 	if err != nil {
diff --git a/cmd/geth/main.go b/cmd/geth/main.go
index bdb7fad62a..16c899f064 100644
--- a/cmd/geth/main.go
+++ b/cmd/geth/main.go
@@ -84,6 +84,7 @@ var (
 		utils.TxPoolLifetimeFlag,
 		utils.FastSyncFlag,
 		utils.LightModeFlag,
+		utils.ULCModeConfigFlag,
 		utils.SyncModeFlag,
 		utils.LightServFlag,
 		utils.LightPeersFlag,
diff --git a/cmd/utils/flags.go b/cmd/utils/flags.go
index 30edf199c9..e643a85fe3 100644
--- a/cmd/utils/flags.go
+++ b/cmd/utils/flags.go
@@ -56,6 +56,7 @@ import (
 	"github.com/ethereum/go-ethereum/params"
 	whisper "github.com/ethereum/go-ethereum/whisper/whisperv5"
 	"gopkg.in/urfave/cli.v1"
+	"encoding/json"
 )
 
 var (
@@ -163,6 +164,10 @@ var (
 		Name:  "light",
 		Usage: "Enable light client mode",
 	}
+	ULCModeConfigFlag = cli.StringFlag{
+		Name:  "ulcconfig",
+		Usage: "Config file to use for ULC mode",
+	}
 	defaultSyncMode = eth.DefaultConfig.SyncMode
 	SyncModeFlag    = TextMarshalerFlag{
 		Name:  "syncmode",
@@ -718,6 +723,42 @@ func setIPC(ctx *cli.Context, cfg *node.Config) {
 	}
 }
 
+// SetULC setup ULC config from file if given.
+func SetULC(ctx *cli.Context, cfg *eth.Config, p2pCfg *p2p.Config) {
+	path := ctx.GlobalString(ULCModeConfigFlag.Name)
+	if path == "" {
+		return
+	}
+
+	cfgData, err := ioutil.ReadFile(path)
+	if err != nil {
+		Fatalf("Failed to read ULC config file: %v", err)
+	}
+
+	err = json.Unmarshal(cfgData, &cfg.ULC)
+	if err != nil {
+		Fatalf(err.Error())
+	}
+
+	if len(cfg.ULC.TrustedNodes) == 0 {
+		return
+	}
+
+	if cfg.ULC.MinTrustedFraction <= 0 || cfg.ULC.MinTrustedFraction > 100 {
+		cfg.ULC.MinTrustedFraction = eth.DefaultConfig.ULC.MinTrustedFraction
+	}
+
+	p2pCfg.TrustedNodes = make([]*discover.Node, 0, len(cfg.ULC.TrustedNodes))
+	for _, url := range cfg.ULC.TrustedNodes {
+		node, err := discover.ParseNode(url)
+		if err != nil {
+			log.Error("Trusted node URL invalid", "enode", url, "err", err)
+			continue
+		}
+		p2pCfg.TrustedNodes = append(p2pCfg.TrustedNodes, node)
+	}
+}
+
 // makeDatabaseHandles raises out the number of allowed file handles per process
 // for Geth and returns half of the allowance to assign to the database.
 func makeDatabaseHandles() int {
diff --git a/eth/config.go b/eth/config.go
index 383cd6783c..545191a490 100644
--- a/eth/config.go
+++ b/eth/config.go
@@ -42,6 +42,7 @@ var DefaultConfig = Config{
 		DatasetsInMem:  1,
 		DatasetsOnDisk: 2,
 	},
+	ULC: &ULCConfig{MinTrustedFraction: 75},
 	NetworkId:     1,
 	LightPeers:    20,
 	DatabaseCache: 128,
@@ -83,6 +84,9 @@ type Config struct {
 	LightServ  int `toml:",omitempty"` // Maximum percentage of time allowed for serving LES requests
 	LightPeers int `toml:",omitempty"` // Maximum number of LES client peers
 
+	// Ultra Light client options
+	ULC *ULCConfig `toml:",omitempty"`
+
 	// Database options
 	SkipBcVersionCheck bool `toml:"-"`
 	DatabaseHandles    int  `toml:"-"`
diff --git a/eth/gen_config.go b/eth/gen_config.go
index e2d50e1f66..fb27d7cad6 100644
--- a/eth/gen_config.go
+++ b/eth/gen_config.go
@@ -13,32 +13,28 @@ import (
 	"github.com/ethereum/go-ethereum/eth/gasprice"
 )
 
+var _ = (*configMarshaling)(nil)
+
 func (c Config) MarshalTOML() (interface{}, error) {
 	type Config struct {
 		Genesis                 *core.Genesis `toml:",omitempty"`
 		NetworkId               uint64
 		SyncMode                downloader.SyncMode
-		LightServ               int  `toml:",omitempty"`
-		LightPeers              int  `toml:",omitempty"`
-		MaxPeers                int  `toml:"-"`
-		SkipBcVersionCheck      bool `toml:"-"`
-		DatabaseHandles         int  `toml:"-"`
+		LightServ               int        `toml:",omitempty"`
+		LightPeers              int        `toml:",omitempty"`
+		ULC                     *ULCConfig `toml:",omitempty"`
+		SkipBcVersionCheck      bool       `toml:"-"`
+		DatabaseHandles         int        `toml:"-"`
 		DatabaseCache           int
 		Etherbase               common.Address `toml:",omitempty"`
 		MinerThreads            int            `toml:",omitempty"`
 		ExtraData               hexutil.Bytes  `toml:",omitempty"`
 		GasPrice                *big.Int
-		EthashCacheDir          string
-		EthashCachesInMem       int
-		EthashCachesOnDisk      int
-		EthashDatasetDir        string
-		EthashDatasetsInMem     int
-		EthashDatasetsOnDisk    int
+		Ethash                  ethash.Config
 		TxPool                  core.TxPoolConfig
 		GPO                     gasprice.Config
 		EnablePreimageRecording bool
-		DocRoot                 string      `toml:"-"`
-		PowMode                 ethash.Mode `toml:"-"`
+		DocRoot                 string `toml:"-"`
 	}
 	var enc Config
 	enc.Genesis = c.Genesis
@@ -46,6 +42,7 @@ func (c Config) MarshalTOML() (interface{}, error) {
 	enc.SyncMode = c.SyncMode
 	enc.LightServ = c.LightServ
 	enc.LightPeers = c.LightPeers
+	enc.ULC = c.ULC
 	enc.SkipBcVersionCheck = c.SkipBcVersionCheck
 	enc.DatabaseHandles = c.DatabaseHandles
 	enc.DatabaseCache = c.DatabaseCache
@@ -53,17 +50,11 @@ func (c Config) MarshalTOML() (interface{}, error) {
 	enc.MinerThreads = c.MinerThreads
 	enc.ExtraData = c.ExtraData
 	enc.GasPrice = c.GasPrice
-	enc.EthashCacheDir = c.Ethash.CacheDir
-	enc.EthashCachesInMem = c.Ethash.CachesInMem
-	enc.EthashCachesOnDisk = c.Ethash.CachesOnDisk
-	enc.EthashDatasetDir = c.Ethash.DatasetDir
-	enc.EthashDatasetsInMem = c.Ethash.DatasetsInMem
-	enc.EthashDatasetsOnDisk = c.Ethash.DatasetsOnDisk
+	enc.Ethash = c.Ethash
 	enc.TxPool = c.TxPool
 	enc.GPO = c.GPO
 	enc.EnablePreimageRecording = c.EnablePreimageRecording
 	enc.DocRoot = c.DocRoot
-	enc.PowMode = c.Ethash.PowMode
 	return &enc, nil
 }
 
@@ -72,27 +63,21 @@ func (c *Config) UnmarshalTOML(unmarshal func(interface{}) error) error {
 		Genesis                 *core.Genesis `toml:",omitempty"`
 		NetworkId               *uint64
 		SyncMode                *downloader.SyncMode
-		LightServ               *int  `toml:",omitempty"`
-		LightPeers              *int  `toml:",omitempty"`
-		MaxPeers                *int  `toml:"-"`
-		SkipBcVersionCheck      *bool `toml:"-"`
-		DatabaseHandles         *int  `toml:"-"`
+		LightServ               *int       `toml:",omitempty"`
+		LightPeers              *int       `toml:",omitempty"`
+		ULC                     *ULCConfig `toml:",omitempty"`
+		SkipBcVersionCheck      *bool      `toml:"-"`
+		DatabaseHandles         *int       `toml:"-"`
 		DatabaseCache           *int
 		Etherbase               *common.Address `toml:",omitempty"`
 		MinerThreads            *int            `toml:",omitempty"`
 		ExtraData               hexutil.Bytes   `toml:",omitempty"`
 		GasPrice                *big.Int
-		EthashCacheDir          *string
-		EthashCachesInMem       *int
-		EthashCachesOnDisk      *int
-		EthashDatasetDir        *string
-		EthashDatasetsInMem     *int
-		EthashDatasetsOnDisk    *int
+		Ethash                  *ethash.Config
 		TxPool                  *core.TxPoolConfig
 		GPO                     *gasprice.Config
 		EnablePreimageRecording *bool
-		DocRoot                 *string      `toml:"-"`
-		PowMode                 *ethash.Mode `toml:"-"`
+		DocRoot                 *string `toml:"-"`
 	}
 	var dec Config
 	if err := unmarshal(&dec); err != nil {
@@ -113,6 +98,9 @@ func (c *Config) UnmarshalTOML(unmarshal func(interface{}) error) error {
 	if dec.LightPeers != nil {
 		c.LightPeers = *dec.LightPeers
 	}
+	if dec.ULC != nil {
+		c.ULC = dec.ULC
+	}
 	if dec.SkipBcVersionCheck != nil {
 		c.SkipBcVersionCheck = *dec.SkipBcVersionCheck
 	}
@@ -134,23 +122,8 @@ func (c *Config) UnmarshalTOML(unmarshal func(interface{}) error) error {
 	if dec.GasPrice != nil {
 		c.GasPrice = dec.GasPrice
 	}
-	if dec.EthashCacheDir != nil {
-		c.Ethash.CacheDir = *dec.EthashCacheDir
-	}
-	if dec.EthashCachesInMem != nil {
-		c.Ethash.CachesInMem = *dec.EthashCachesInMem
-	}
-	if dec.EthashCachesOnDisk != nil {
-		c.Ethash.CachesOnDisk = *dec.EthashCachesOnDisk
-	}
-	if dec.EthashDatasetDir != nil {
-		c.Ethash.DatasetDir = *dec.EthashDatasetDir
-	}
-	if dec.EthashDatasetsInMem != nil {
-		c.Ethash.DatasetsInMem = *dec.EthashDatasetsInMem
-	}
-	if dec.EthashDatasetsOnDisk != nil {
-		c.Ethash.DatasetsOnDisk = *dec.EthashDatasetsOnDisk
+	if dec.Ethash != nil {
+		c.Ethash = *dec.Ethash
 	}
 	if dec.TxPool != nil {
 		c.TxPool = *dec.TxPool
@@ -164,8 +137,5 @@ func (c *Config) UnmarshalTOML(unmarshal func(interface{}) error) error {
 	if dec.DocRoot != nil {
 		c.DocRoot = *dec.DocRoot
 	}
-	if dec.PowMode != nil {
-		c.Ethash.PowMode = *dec.PowMode
-	}
 	return nil
 }
diff --git a/eth/ulc_config.go b/eth/ulc_config.go
new file mode 100644
index 0000000000..b86d191239
--- /dev/null
+++ b/eth/ulc_config.go
@@ -0,0 +1,7 @@
+package eth
+
+// Ultra Light client options
+type ULCConfig struct {
+	TrustedNodes       []string `toml:",omitempty"` // A list of trusted servers
+	MinTrustedFraction int      `toml:",omitempty"` // Minimum percentage of connected trusted servers to validate trusted (1-100)
+}