diff --git a/internal/api/captcha.go b/internal/api/captcha.go
index 9cedb3d3e..9a0c6f3ca 100644
--- a/internal/api/captcha.go
+++ b/internal/api/captcha.go
@@ -41,7 +41,7 @@ func (c *CaptchaApi) VerifyCaptcha(ctx *gin.Context) {
 	}
 	resp, err := c.Client.VerifyCaptcha(ctx, req)
 	if err != nil {
-		log.ZError(ctx, "captcha verify rpc failed", err, "captchaID", req.GetCaptchaID(), "x", req.GetX(), "y", req.GetY())
+		log.ZError(ctx, "captcha verify rpc failed", err, "captchaID", req.GetCaptchaID(), "clickCount", len(req.GetClickPoints()))
 		apiresp.GinError(ctx, err)
 		return
 	}
diff --git a/internal/api/router.go b/internal/api/router.go
index 2e3cb02ad..328b83db2 100644
--- a/internal/api/router.go
+++ b/internal/api/router.go
@@ -9,10 +9,10 @@ import (
 	pbAuth "github.com/openimsdk/protocol/auth"
 	pbcaptcha "github.com/openimsdk/protocol/captcha"
 	"github.com/openimsdk/protocol/conversation"
+	pbcrypto "github.com/openimsdk/protocol/crypto"
 	"github.com/openimsdk/protocol/group"
 	"github.com/openimsdk/protocol/msg"
 	"github.com/openimsdk/protocol/relation"
-	pbcrypto "github.com/openimsdk/protocol/crypto"
 	"github.com/openimsdk/protocol/rtc"
 	"github.com/openimsdk/protocol/third"
 	"github.com/openimsdk/protocol/user"
@@ -334,8 +334,8 @@ func newGinRouter(ctx context.Context, client discovery.SvcDiscoveryRegistry, co
 		phoneGroup := r.Group("/phone")
 		phoneGroup.POST("/get_sn_info", phoneSN.GetSNInfo)
 		phoneGroup.POST("/set_sn_info", phoneSN.SetSNInfo)
-  }
-  {
+	}
+	{
 		rc := NewRtcApi(rtc.NewRtcServiceClient(rtcConn))
 		rtcGroup := r.Group("/rtc")
 		rtcGroup.POST("/signal_message_assemble", rc.SignalMessageAssemble)
diff --git a/internal/msggateway/message_handler.go b/internal/msggateway/message_handler.go
index 2706540a0..cb1b2ea27 100644
--- a/internal/msggateway/message_handler.go
+++ b/internal/msggateway/message_handler.go
@@ -188,6 +188,9 @@ func (g *GrpcHandler) SendSignalMessage(ctx context.Context, data *Req) ([]byte,
 		}
 		assembleReq.SignalReq = &signalReq
 	}
+
+	log.ZDebug(ctx, "SendSignalMessage", "assembleReq", assembleReq)
+
 	resp, err := g.rtcClient.RtcServiceClient.SignalMessageAssemble(ctx, &assembleReq)
 	if err != nil {
 		log.ZError(ctx, "SendSignalMessage", err, "r", err.Error())
diff --git a/internal/rpc/captcha/captcha.go b/internal/rpc/captcha/captcha.go
index 206b376e5..4b5e6c833 100644
--- a/internal/rpc/captcha/captcha.go
+++ b/internal/rpc/captcha/captcha.go
@@ -2,6 +2,7 @@ package captcha
 
 import (
 	"context"
+	"encoding/json"
 	"errors"
 	"time"
 
@@ -17,10 +18,17 @@ import (
 	"go.mongodb.org/mongo-driver/mongo/options"
 	"google.golang.org/grpc"
 
-	"github.com/wenlng/go-captcha/v2/base/option"
-	"github.com/wenlng/go-captcha/v2/slide"
+	"github.com/wenlng/go-captcha/v2/click"
 )
 
+// alphanumChars is the character pool for the click captcha.
+// Visually ambiguous characters (I, O, 0, 1, l) are excluded.
+var alphanumChars = []string{
+	"A", "B", "C", "D", "E", "F", "G", "H", "J", "K",
+	"L", "M", "N", "P", "Q", "R", "S", "T", "U", "V",
+	"W", "X", "Y", "Z", "2", "3", "4", "5", "6", "7", "8", "9",
+}
+
 type Config struct {
 	RpcConfig     config.Captcha
 	MongodbConfig config.Mongo
@@ -31,14 +39,14 @@ type Config struct {
 type server struct {
 	pbcaptcha.UnimplementedCaptchaServer
 	conf       config.Captcha
-	capt       slide.Captcha
+	capt       click.Captcha
 	collection *mongo.Collection
 }
 
+// captchaDoc is the MongoDB document that stores the verification answer.
 type captchaDoc struct {
 	CaptchaID  string    `bson:"captcha_id"`
-	X          int       `bson:"x"`
-	Y          int       `bson:"y"`
+	DotsJSON   string    `bson:"dots_json"` // JSON-encoded map[int]*click.Dot (answer dots)
 	ExpiredAt  time.Time `bson:"expired_at"`
 	CreateTime time.Time `bson:"create_time"`
 	VerifyTime time.Time `bson:"verify_time,omitempty"`
@@ -66,17 +74,15 @@ func Start(ctx context.Context, cfg *Config, _ discovery.SvcDiscoveryRegistry, g
 		return err
 	}
 
-	resources, err := loadResources()
+	capt, err := buildClickCaptcha()
 	if err != nil {
-		log.ZError(ctx, "captcha load resources failed", err)
+		log.ZError(ctx, "captcha build click captcha failed", err)
 		return err
 	}
 
-	builder := slide.NewBuilder()
-	builder.SetResources(resources...)
 	s := &server{
 		conf:       cfg.RpcConfig,
-		capt:       builder.Make(),
+		capt:       capt,
 		collection: collection,
 	}
 	if s.conf.ExpireSeconds <= 0 {
@@ -95,24 +101,31 @@ func (s *server) GenerateCaptcha(ctx context.Context, _ *pbcaptcha.GenerateCaptc
 		log.ZError(ctx, "captcha generate failed", err)
 		return nil, err
 	}
-	block := captData.GetData()
-	masterImage, err := captData.GetMasterImage().ToBase64DataWithQuality(option.QualityNone)
+
+	dots := captData.GetData() // answer dots: map[int]*click.Dot
+	masterImage, err := captData.GetMasterImage().ToBase64DataWithQuality(0)
 	if err != nil {
 		log.ZError(ctx, "captcha encode master image failed", err)
 		return nil, err
 	}
-	tileImage, err := captData.GetTileImage().ToBase64Data()
+	thumbImage, err := captData.GetThumbImage().ToBase64Data()
 	if err != nil {
-		log.ZError(ctx, "captcha encode tile image failed", err)
+		log.ZError(ctx, "captcha encode thumb image failed", err)
 		return nil, err
 	}
+
+	dotsJSON, err := json.Marshal(dots)
+	if err != nil {
+		log.ZError(ctx, "captcha marshal dots failed", err)
+		return nil, err
+	}
+
 	id := uuid.NewString()
 	now := time.Now()
 	expiredAt := now.Add(time.Duration(s.conf.ExpireSeconds) * time.Second)
 	_, err = s.collection.InsertOne(ctx, captchaDoc{
 		CaptchaID:  id,
-		X:          block.X,
-		Y:          block.Y,
+		DotsJSON:   string(dotsJSON),
 		ExpiredAt:  expiredAt,
 		CreateTime: now,
 	})
@@ -120,26 +133,26 @@ func (s *server) GenerateCaptcha(ctx context.Context, _ *pbcaptcha.GenerateCaptc
 		log.ZError(ctx, "captcha insert mongodb failed", err, "captchaID", id)
 		return nil, err
 	}
+
+	log.ZDebug(ctx, "captcha generated", "captchaID", id, "dotCount", len(dots), "expireAt", expiredAt.Unix())
 	return &pbcaptcha.GenerateCaptchaResp{
 		CaptchaID:   id,
 		MasterImage: masterImage,
-		TileImage:   tileImage,
-		TileY:       int32(block.DY),
+		ThumbImage:  thumbImage,
 		ExpireAt:    expiredAt.Unix(),
 	}, nil
 }
 
 func (s *server) VerifyCaptcha(ctx context.Context, req *pbcaptcha.VerifyCaptchaReq) (*pbcaptcha.VerifyCaptchaResp, error) {
+	log.ZDebug(ctx, "captcha verify request", "captchaID", req.CaptchaID, "clickCount", len(req.ClickPoints))
+
 	now := time.Now()
 	filter := bson.M{
 		"captcha_id":  req.CaptchaID,
 		"verify_time": bson.M{"$exists": false},
 	}
-	update := bson.M{
-		"$set": bson.M{
-			"verify_time": now,
-		},
-	}
+	update := bson.M{"$set": bson.M{"verify_time": now}}
+
 	var doc captchaDoc
 	err := s.collection.FindOneAndUpdate(
 		ctx,
@@ -159,9 +172,41 @@ func (s *server) VerifyCaptcha(ctx context.Context, req *pbcaptcha.VerifyCaptcha
 		log.ZWarn(ctx, "captcha expired", nil, "captchaID", req.CaptchaID, "expiredAt", doc.ExpiredAt.Unix())
 		return nil, servererrs.ErrFileUploadedExpired.WrapMsg("captcha expired", "captchaID", req.CaptchaID)
 	}
-	success := slide.Validate(int(req.X), int(req.Y), doc.X, doc.Y, s.conf.VerifyPadding)
+
+	// Unmarshal the stored answer dots.
+	var answerDots map[int]*click.Dot
+	if err := json.Unmarshal([]byte(doc.DotsJSON), &answerDots); err != nil {
+		log.ZError(ctx, "captcha unmarshal dots failed", err, "captchaID", req.CaptchaID)
+		return nil, servererrs.ErrDatabase.WrapMsg("internal captcha data error")
+	}
+
+	success := validateClickPoints(req.ClickPoints, answerDots, s.conf.VerifyPadding)
 	if !success {
-		log.ZError(ctx, "captcha validate failed", nil, "captchaID", req.CaptchaID, "x", req.X, "y", req.Y, "docX", doc.X, "docY", doc.Y)
+		log.ZError(ctx, "captcha validate failed", nil,
+			"captchaID", req.CaptchaID,
+			"clickCount", len(req.ClickPoints),
+			"answerCount", len(answerDots),
+		)
+	} else {
+		log.ZDebug(ctx, "captcha validate success", "captchaID", req.CaptchaID)
 	}
 	return &pbcaptcha.VerifyCaptchaResp{Success: success}, nil
 }
+
+// validateClickPoints checks that each user click point falls within the
+// bounding box of the corresponding answer dot (in order).
+func validateClickPoints(points []*pbcaptcha.ClickPoint, dots map[int]*click.Dot, padding int) bool {
+	if len(points) != len(dots) {
+		return false
+	}
+	for i, pt := range points {
+		dot, ok := dots[i]
+		if !ok {
+			return false
+		}
+		if !click.Validate(int(pt.X), int(pt.Y), dot.X, dot.Y, dot.Width, dot.Height, padding) {
+			return false
+		}
+	}
+	return true
+}
diff --git a/internal/rpc/captcha/embed.go b/internal/rpc/captcha/embed.go
index 9ec2e8d8f..c0c0372bf 100644
--- a/internal/rpc/captcha/embed.go
+++ b/internal/rpc/captcha/embed.go
@@ -2,12 +2,7 @@ package captcha
 
 import "embed"
 
-// resourceFS embeds background images and tile images at compile time.
-// Background images come from go-captcha-resources (sourcedata/images/image-{1..5}).
-// Tile images come from go-captcha-resources (sourcedata/tiles/tile-{1..4}):
-//   overlay.png  → GraphImage.OverlayImage
-//   shadow.png   → GraphImage.ShadowImage
-//   mask.png     → GraphImage.MaskImage
+// resourceFS embeds background images for the click captcha at compile time.
 //
-//go:embed resources/images/*.jpg resources/tiles/*/*.png
+//go:embed resources/images/*.jpg
 var resourceFS embed.FS
diff --git a/internal/rpc/captcha/resources.go b/internal/rpc/captcha/resources.go
index 1264ef1fd..d02ce1c29 100644
--- a/internal/rpc/captcha/resources.go
+++ b/internal/rpc/captcha/resources.go
@@ -6,24 +6,42 @@ import (
 	_ "image/jpeg"
 	_ "image/png"
 
-	"github.com/wenlng/go-captcha/v2/slide"
+	"github.com/golang/freetype"
+	"github.com/golang/freetype/truetype"
+	"github.com/wenlng/go-captcha/v2/base/option"
+	"github.com/wenlng/go-captcha/v2/click"
+	"golang.org/x/image/font/gofont/goregular"
 )
 
-// loadResources reads the embedded files and returns slide.Resource options
-// ready to be passed to slide.NewBuilder().SetResources(...).
-func loadResources() ([]slide.Resource, error) {
-	backgrounds, err := loadBackgrounds()
+// buildClickCaptcha constructs a click.Captcha instance configured with
+// alphanumeric characters, a bundled Go font, and the embedded background images.
+func buildClickCaptcha() (click.Captcha, error) {
+	font, err := loadGoRegularFont()
 	if err != nil {
-		return nil, fmt.Errorf("load captcha backgrounds: %w", err)
+		return nil, fmt.Errorf("load font: %w", err)
 	}
-	graphImages, err := loadGraphImages()
+	backgrounds, err := loadBackgrounds()
 	if err != nil {
-		return nil, fmt.Errorf("load captcha graph images: %w", err)
+		return nil, fmt.Errorf("load captcha backgrounds: %w", err)
 	}
-	return []slide.Resource{
-		slide.WithBackgrounds(backgrounds),
-		slide.WithGraphImages(graphImages),
-	}, nil
+
+	builder := click.NewBuilder(
+		click.WithRangeLen(option.RangeVal{Min: 6, Max: 8}),
+		click.WithRangeVerifyLen(option.RangeVal{Min: 3, Max: 4}),
+		click.WithRangeSize(option.RangeVal{Min: 26, Max: 34}),
+		click.WithDisplayShadow(true),
+	)
+	builder.SetResources(
+		click.WithChars(alphanumChars),
+		click.WithFonts([]*truetype.Font{font}),
+		click.WithBackgrounds(backgrounds),
+	)
+	return builder.Make(), nil
+}
+
+// loadGoRegularFont parses the bundled Go Regular TTF font.
+func loadGoRegularFont() (*truetype.Font, error) {
+	return freetype.ParseFont(goregular.TTF)
 }
 
 // loadBackgrounds decodes the embedded JPEG background images.
@@ -41,32 +59,6 @@ func loadBackgrounds() ([]image.Image, error) {
 	return images, nil
 }
 
-// loadGraphImages decodes the 4 sets of tile overlay/shadow/mask PNG images.
-func loadGraphImages() ([]*slide.GraphImage, error) {
-	const count = 4
-	graphs := make([]*slide.GraphImage, 0, count)
-	for i := 1; i <= count; i++ {
-		overlay, err := decodeEmbedImage(fmt.Sprintf("resources/tiles/tile-%d/overlay.png", i))
-		if err != nil {
-			return nil, fmt.Errorf("decode tile-%d overlay: %w", i, err)
-		}
-		shadow, err := decodeEmbedImage(fmt.Sprintf("resources/tiles/tile-%d/shadow.png", i))
-		if err != nil {
-			return nil, fmt.Errorf("decode tile-%d shadow: %w", i, err)
-		}
-		mask, err := decodeEmbedImage(fmt.Sprintf("resources/tiles/tile-%d/mask.png", i))
-		if err != nil {
-			return nil, fmt.Errorf("decode tile-%d mask: %w", i, err)
-		}
-		graphs = append(graphs, &slide.GraphImage{
-			OverlayImage: overlay,
-			ShadowImage:  shadow,
-			MaskImage:    mask,
-		})
-	}
-	return graphs, nil
-}
-
 func decodeEmbedImage(path string) (image.Image, error) {
 	f, err := resourceFS.Open(path)
 	if err != nil {
diff --git a/internal/rpc/captcha/resources/images/image-1.jpg b/internal/rpc/captcha/resources/images/image-1.jpg
index f3be01297..a392ce012 100644
Binary files a/internal/rpc/captcha/resources/images/image-1.jpg and b/internal/rpc/captcha/resources/images/image-1.jpg differ
diff --git a/internal/rpc/captcha/resources/images/image-2.jpg b/internal/rpc/captcha/resources/images/image-2.jpg
index ca35458f6..36e867881 100644
Binary files a/internal/rpc/captcha/resources/images/image-2.jpg and b/internal/rpc/captcha/resources/images/image-2.jpg differ
diff --git a/internal/rpc/captcha/resources/images/image-3.jpg b/internal/rpc/captcha/resources/images/image-3.jpg
index 104aeb77a..77cdb21db 100644
Binary files a/internal/rpc/captcha/resources/images/image-3.jpg and b/internal/rpc/captcha/resources/images/image-3.jpg differ
diff --git a/internal/rpc/captcha/resources/images/image-4.jpg b/internal/rpc/captcha/resources/images/image-4.jpg
index dc12c2bf4..5fea0bd09 100644
Binary files a/internal/rpc/captcha/resources/images/image-4.jpg and b/internal/rpc/captcha/resources/images/image-4.jpg differ
diff --git a/internal/rpc/captcha/resources/images/image-5.jpg b/internal/rpc/captcha/resources/images/image-5.jpg
index 4a11044a9..601702436 100644
Binary files a/internal/rpc/captcha/resources/images/image-5.jpg and b/internal/rpc/captcha/resources/images/image-5.jpg differ
diff --git a/internal/rpc/rtc/signal.go b/internal/rpc/rtc/signal.go
index b20e02d36..a3efb70c5 100644
--- a/internal/rpc/rtc/signal.go
+++ b/internal/rpc/rtc/signal.go
@@ -48,7 +48,7 @@ func (s *rtcServer) SignalMessageAssemble(ctx context.Context, req *rtc.SignalMe
 	)
 	switch payload := req.SignalReq.Payload.(type) {
 	case *rtc.SignalReq_Invite:
-		log.ZInfo(ctx, "SignalMessageAssemble", "payload", payload.Invite)
+		log.ZDebug(ctx, "SignalMessageAssemble", "payload", payload.Invite)
 		r, err := s.handleInvite(ctx, payload.Invite, req.SignalReq)
 		resp.Payload = &rtc.SignalResp_Invite{Invite: r}
 		respErr = err
diff --git a/openim-sdk-core b/openim-sdk-core
new file mode 120000
index 000000000..889d82c06
--- /dev/null
+++ b/openim-sdk-core
@@ -0,0 +1 @@
+../openim-sdk-core-origin
\ No newline at end of file
diff --git a/protocol b/protocol
index 9f0b38eb5..ed16bd0c4 160000
--- a/protocol
+++ b/protocol
@@ -1 +1 @@
-Subproject commit 9f0b38eb5c5015da3969d6711a140c3ba12956bb
+Subproject commit ed16bd0c4049d722e7b605c3f314ee661b9bc4e1
diff --git a/start-config.yml b/start-config.yml
index d06738143..52afa4cab 100644
--- a/start-config.yml
+++ b/start-config.yml
@@ -13,6 +13,7 @@ serviceBinaries:
   openim-rpc-msg: 1
   openim-rpc-rtc: 1
   openim-rpc-third: 1
+  openim-rpc-crypto: 1
 toolBinaries:
   - check-free-memory
   - check-component