diff --git a/README.md b/README.md
index 25186be..b9dad6c 100644
--- a/README.md
+++ b/README.md
@@ -38,19 +38,7 @@ CGO_ENABLED=0 GOOS=linux GOARCH=arm GOARM=7 go build -o bin/server-linux-armv7 .
 CGO_ENABLED=0 GOOS=linux GOARCH=arm GOARM=7 go build -o bin/peer-linux-armv7 ./cmd/peer
 ```
 
-## Deploy
 
-把对应架构的二进制拷到目标机器，并赋予可执行权限。
-
-```bash
-scp bin/server-linux-amd64 user@server-host:~/omnisocket/server
-scp bin/peer-linux-amd64 user@peer-host:~/omnisocket/peer
-```
-
-```bash
-ssh user@server-host 'chmod +x ~/omnisocket/server'
-ssh user@peer-host 'chmod +x ~/omnisocket/peer'
-```
 
 ## Run On Different Machines
 
diff --git a/cmd/internal/latencylog/summary.go b/cmd/internal/latencylog/summary.go
index 13337b2..7d6429a 100644
--- a/cmd/internal/latencylog/summary.go
+++ b/cmd/internal/latencylog/summary.go
@@ -31,13 +31,14 @@ type Summary struct {
 	BodySize    int                  `json:"body_size"`           //消息体大小（字节数）
 	Timestamps  map[string]int64     `json:"timestamps"`          //事件时间戳，key 是事件名称，value 是 UnixNano 时间戳
 
-	AProcessingLatencyNS                  *int64   `json:"a_processing_latency_ns,omitempty"`                      // A 处理时延：A_TX_SCHED - A_APP_PREP_BEGIN
-	AQueueLatencyNS                       *int64   `json:"a_queue_latency_ns,omitempty"`                           // A 排队时延：A_TX_SOFTWARE - A_TX_SCHED
-	ABTransportPropagationBQueueLatencyNS *int64   `json:"a_b_transport_propagation_b_queue_latency_ns,omitempty"` // A-B 传输时延 + B 排队时延：B_APP_RECV - A_TX_SOFTWARE
-	BKernelReceivePathLatencyNS           *int64   `json:"b_kernel_receive_path_latency_ns,omitempty"`             // B 内核接收路径近似：B_APP_RECV - B_RX_SOFTWARE
-	BProcessingLatencyNS                  *int64   `json:"b_processing_latency_ns,omitempty"`                      // B 处理时延：B_PERSIST_END - B_APP_RECV
-	EndToEndLatencyNS                     *int64   `json:"end_to_end_latency_ns,omitempty"`                        // 端到端时延：B_PERSIST_END - A_APP_PREP_BEGIN
-	MissingTimestamps                     []string `json:"missing_timestamps,omitempty"`                           // 缺失的时间戳列表，包含 requiredTimestampNames 中但在原始事件中没有的事件名称
+	AProcessingLatencyNS        *int64   `json:"a_processing_latency_ns,omitempty"`          // A 处理时延：A_TX_SCHED - A_APP_PREP_BEGIN
+	AQueueLatencyNS             *int64   `json:"a_queue_latency_ns,omitempty"`               // A 排队时延：A_TX_SOFTWARE - A_TX_SCHED
+	ABTransportPropagationNS    *int64   `json:"a_b_transport_propagation_ns,omitempty"`     // A-B 传输+传播时延近似：B_APP_RECV - A_TX_SOFTWARE
+	BKernelReceivePathLatencyNS *int64   `json:"b_kernel_receive_path_latency_ns,omitempty"` // B 内核接收路径近似：B_APP_RECV - B_RX_SOFTWARE
+	BProcessingLatencyNS        *int64   `json:"b_processing_latency_ns,omitempty"`          // B 处理时延：B_PERSIST_END - B_APP_RECV
+	EndToEndLatencyNS           *int64   `json:"end_to_end_latency_ns,omitempty"`            // 端到端时延：B_PERSIST_END - A_APP_PREP_BEGIN
+	ApproxRTTNS                 *int64   `json:"approx_rtt_ns,omitempty"`                    // 近似 RTT：首条反向应答的 B_APP_RECV - 当前请求的 A_TX_SOFTWARE
+	MissingTimestamps           []string `json:"missing_timestamps,omitempty"`               // 缺失的时间戳列表，包含 requiredTimestampNames 中但在原始事件中没有的事件名称
 }
 
 // LoadEventsFromFiles 从JSONL 原始日志文件中加载事件。
@@ -132,9 +133,15 @@ func SummarizeEvents(events []Event) []Summary {
 		}
 	}
 
-	summaries := make([]Summary, 0, len(grouped))
+	summaryPointers := make([]*Summary, 0, len(grouped))
 	for _, summary := range grouped {
 		completeSummary(summary) //补全时延指标和缺失时间戳信息
+		summaryPointers = append(summaryPointers, summary)
+	}
+	assignApproxRTTs(summaryPointers)
+
+	summaries := make([]Summary, 0, len(summaryPointers))
+	for _, summary := range summaryPointers {
 		summaries = append(summaries, *summary)
 	}
 	//对整理结果进行排序，先按发送方、再按接收方、再按消息 ID、最后按消息类型排序，保证输出的稳定性和可读性。
@@ -195,7 +202,7 @@ func completeSummary(summary *Summary) {
 		summary.AQueueLatencyNS = value
 	}
 	if value := subtractIfPresent(summary.Timestamps, EventBAppRecv, EventATXSoftware); value != nil {
-		summary.ABTransportPropagationBQueueLatencyNS = value
+		summary.ABTransportPropagationNS = value
 	}
 	if value := subtractIfPresent(summary.Timestamps, EventBAppRecv, EventBRXSoftware); value != nil {
 		summary.BKernelReceivePathLatencyNS = value
@@ -208,6 +215,90 @@ func completeSummary(summary *Summary) {
 	}
 }
 
+type routeKey struct {
+	From string
+	To   string
+}
+
+func assignApproxRTTs(summaries []*Summary) {
+	grouped := make(map[routeKey][]*Summary)
+	for _, summary := range summaries {
+		grouped[routeKey{From: summary.From, To: summary.To}] = append(grouped[routeKey{From: summary.From, To: summary.To}], summary)
+	}
+
+	for key, requests := range grouped {
+		replies := grouped[routeKey{From: key.To, To: key.From}]
+		if len(replies) == 0 {
+			continue
+		}
+
+		assignApproxRTTsForRoute(
+			sortSummariesByTimestamp(requests, EventBAppRecv),
+			sortSummariesByTimestamp(replies, EventATXSoftware),
+		)
+	}
+}
+
+func assignApproxRTTsForRoute(requests, replies []*Summary) {
+	replyIndex := 0
+	for _, request := range requests {
+		requestReceivedAtResponder, ok := request.Timestamps[EventBAppRecv]
+		if !ok {
+			continue
+		}
+
+		for replyIndex < len(replies) {
+			reply := replies[replyIndex]
+			replySentAtResponder, ok := reply.Timestamps[EventATXSoftware]
+			if !ok {
+				replyIndex++
+				continue
+			}
+			if replySentAtResponder < requestReceivedAtResponder {
+				replyIndex++
+				continue
+			}
+
+			if value := subtractSummaryTimestamps(reply, EventBAppRecv, request, EventATXSoftware); value != nil {
+				request.ApproxRTTNS = value
+			}
+			replyIndex++
+			break
+		}
+	}
+}
+
+func sortSummariesByTimestamp(summaries []*Summary, eventName string) []*Summary {
+	sorted := append([]*Summary(nil), summaries...)
+	sort.SliceStable(sorted, func(i, j int) bool {
+		leftTS, leftOK := sorted[i].Timestamps[eventName]
+		rightTS, rightOK := sorted[j].Timestamps[eventName]
+		switch {
+		case leftOK && rightOK:
+			if leftTS != rightTS {
+				return leftTS < rightTS
+			}
+		case leftOK:
+			return true
+		case rightOK:
+			return false
+		}
+
+		if sorted[i].MessageID != sorted[j].MessageID {
+			return sorted[i].MessageID < sorted[j].MessageID
+		}
+		if sorted[i].From != sorted[j].From {
+			return sorted[i].From < sorted[j].From
+		}
+		if sorted[i].To != sorted[j].To {
+			return sorted[i].To < sorted[j].To
+		}
+
+		return sorted[i].MessageType < sorted[j].MessageType
+	})
+	return sorted
+}
+
 // 返回 requiredTimestampNames 中哪些在给定的 timestamps 中缺失。
 func missingTimestampNames(timestamps map[string]int64) []string {
 	var missing []string
@@ -235,6 +326,20 @@ func subtractIfPresent(timestamps map[string]int64, endName, beginName string) *
 	return &value
 }
 
+func subtractSummaryTimestamps(endSummary *Summary, endName string, beginSummary *Summary, beginName string) *int64 {
+	end, ok := endSummary.Timestamps[endName]
+	if !ok {
+		return nil
+	}
+	begin, ok := beginSummary.Timestamps[beginName]
+	if !ok {
+		return nil
+	}
+
+	value := end - begin
+	return &value
+}
+
 // 判断事件是否是业务相关的时延事件（其中一项）
 func IsBusinessEvent(event Event) bool {
 	switch event.Event {
diff --git a/cmd/internal/latencylog/summary_chart.go b/cmd/internal/latencylog/summary_chart.go
index 1953fe9..30b7559 100644
--- a/cmd/internal/latencylog/summary_chart.go
+++ b/cmd/internal/latencylog/summary_chart.go
@@ -215,6 +215,7 @@ const summaryChartHTMLTemplate = `<!doctype html>
           <div class="row-e2e">{{.EndToEnd}}</div>
         </div>
         <div class="row-meta">{{.Subtitle}}</div>
+        <div class="row-meta">{{.ApproxRTT}}</div>
         <div class="bar">
           {{range .Segments}}
           <div class="segment" style="width: {{printf "%.4f" .WidthPercent}}%; background: {{.Color}}" title="{{.Label}}: {{.Value}}"></div>
@@ -262,6 +263,7 @@ type summaryChartRow struct {
 	Title             string
 	Subtitle          string
 	EndToEnd          string
+	ApproxRTT         string
 	MissingTimestamps string
 	Segments          []summaryChartSegment
 }
@@ -314,7 +316,7 @@ func buildSummaryChartPage(summaries []Summary) summaryChartPage {
 		Legend: []summaryChartLegendItem{
 			{Label: "A processing", Color: "var(--a-proc)"},
 			{Label: "A queue", Color: "var(--a-queue)"},
-			{Label: "Transport + B queue", Color: "var(--transport)"},
+			{Label: "A-B transport + propagation", Color: "var(--transport)"},
 			{Label: "B processing", Color: "var(--b-proc)"},
 			{Label: "Unknown / missing", Color: "var(--unknown)"},
 		},
@@ -357,8 +359,12 @@ func buildSummaryChartRow(summary Summary) summaryChartRow {
 		Title:             buildSummaryChartTitle(summary),
 		Subtitle:          buildSummaryChartSubtitle(summary),
 		EndToEnd:          "End-to-end: n/a",
+		ApproxRTT:         "Approx RTT: n/a",
 		MissingTimestamps: strings.Join(summary.MissingTimestamps, ", "),
 	}
+	if summary.ApproxRTTNS != nil && *summary.ApproxRTTNS > 0 {
+		row.ApproxRTT = fmt.Sprintf("Approx RTT: %s", formatLatencyNS(*summary.ApproxRTTNS))
+	}
 
 	if summary.EndToEndLatencyNS == nil || *summary.EndToEndLatencyNS <= 0 {
 		return row
@@ -370,7 +376,7 @@ func buildSummaryChartRow(summary Summary) summaryChartRow {
 	metrics := []summaryChartSegmentMetric{
 		{label: "A processing", value: summary.AProcessingLatencyNS, color: "var(--a-proc)"},
 		{label: "A queue", value: summary.AQueueLatencyNS, color: "var(--a-queue)"},
-		{label: "Transport + B queue", value: summary.ABTransportPropagationBQueueLatencyNS, color: "var(--transport)"},
+		{label: "A-B transport + propagation", value: summary.ABTransportPropagationNS, color: "var(--transport)"},
 		{label: "B processing", value: summary.BProcessingLatencyNS, color: "var(--b-proc)"},
 	}
 
diff --git a/cmd/internal/latencylog/summary_chart_test.go b/cmd/internal/latencylog/summary_chart_test.go
index a7a7d0d..be466ac 100644
--- a/cmd/internal/latencylog/summary_chart_test.go
+++ b/cmd/internal/latencylog/summary_chart_test.go
@@ -18,16 +18,17 @@ func TestWriteSummariesHTMLChart(t *testing.T) {
 
 	summaries := []Summary{
 		{
-			MessageType:                           protocol.MessageTypeText,
-			MessageID:                             7,
-			From:                                  "peer-a",
-			To:                                    "peer-b",
-			BodySize:                              5,
-			AProcessingLatencyNS:                  &aProcessing,
-			AQueueLatencyNS:                       &aQueue,
-			ABTransportPropagationBQueueLatencyNS: &transport,
-			BProcessingLatencyNS:                  &bProcessing,
-			EndToEndLatencyNS:                     &endToEnd,
+			MessageType:              protocol.MessageTypeText,
+			MessageID:                7,
+			From:                     "peer-a",
+			To:                       "peer-b",
+			BodySize:                 5,
+			AProcessingLatencyNS:     &aProcessing,
+			AQueueLatencyNS:          &aQueue,
+			ABTransportPropagationNS: &transport,
+			BProcessingLatencyNS:     &bProcessing,
+			EndToEndLatencyNS:        &endToEnd,
+			ApproxRTTNS:              &endToEnd,
 		},
 		{
 			MessageType:       protocol.MessageTypeFile,
@@ -56,7 +57,9 @@ func TestWriteSummariesHTMLChart(t *testing.T) {
 		"text #7",
 		"peer-a -&gt; peer-b | 5 bytes",
 		"End-to-end: 100.000 ms",
+		"Approx RTT: 100.000 ms",
 		"A processing 20.000 ms",
+		"A-B transport &#43; propagation 40.000 ms",
 		"file #8 (payload.bin)",
 		"Missing timestamps: B_RX_SOFTWARE",
 	} {
diff --git a/cmd/internal/latencylog/summary_test.go b/cmd/internal/latencylog/summary_test.go
index a7a0eb6..e8ac2f8 100644
--- a/cmd/internal/latencylog/summary_test.go
+++ b/cmd/internal/latencylog/summary_test.go
@@ -34,8 +34,8 @@ func TestSummarizeEventsComputesLatencyMetrics(t *testing.T) {
 	if got := ptrValue(summary.AQueueLatencyNS); got != 20 {
 		t.Fatalf("AQueueLatencyNS = %d, want 20", got)
 	}
-	if got := ptrValue(summary.ABTransportPropagationBQueueLatencyNS); got != 80 {
-		t.Fatalf("ABTransportPropagationBQueueLatencyNS = %d, want 80", got)
+	if got := ptrValue(summary.ABTransportPropagationNS); got != 80 {
+		t.Fatalf("ABTransportPropagationNS = %d, want 80", got)
 	}
 	if got := ptrValue(summary.BKernelReceivePathLatencyNS); got != 40 {
 		t.Fatalf("BKernelReceivePathLatencyNS = %d, want 40", got)
@@ -54,6 +54,46 @@ func TestSummarizeEventsComputesLatencyMetrics(t *testing.T) {
 	}
 }
 
+func TestSummarizeEventsComputesApproxRTTByPairingReverseMessages(t *testing.T) {
+	events := []Event{
+		{TsUnixNano: 100, Event: EventAAppPrepBegin, MessageType: protocol.MessageTypeText, MessageID: 1, From: "peer-a", To: "peer-b"},
+		{TsUnixNano: 110, Event: EventATXSoftware, MessageType: protocol.MessageTypeText, MessageID: 1, From: "peer-a", To: "peer-b"},
+		{TsUnixNano: 180, Event: EventBAppRecv, MessageType: protocol.MessageTypeText, MessageID: 1, From: "peer-a", To: "peer-b"},
+		{TsUnixNano: 120, Event: EventAAppPrepBegin, MessageType: protocol.MessageTypeText, MessageID: 2, From: "peer-a", To: "peer-b"},
+		{TsUnixNano: 140, Event: EventATXSoftware, MessageType: protocol.MessageTypeText, MessageID: 2, From: "peer-a", To: "peer-b"},
+		{TsUnixNano: 190, Event: EventBAppRecv, MessageType: protocol.MessageTypeText, MessageID: 2, From: "peer-a", To: "peer-b"},
+		{TsUnixNano: 200, Event: EventAAppPrepBegin, MessageType: protocol.MessageTypeText, MessageID: 11, From: "peer-b", To: "peer-a"},
+		{TsUnixNano: 210, Event: EventATXSoftware, MessageType: protocol.MessageTypeText, MessageID: 11, From: "peer-b", To: "peer-a"},
+		{TsUnixNano: 260, Event: EventBAppRecv, MessageType: protocol.MessageTypeText, MessageID: 11, From: "peer-b", To: "peer-a"},
+		{TsUnixNano: 220, Event: EventAAppPrepBegin, MessageType: protocol.MessageTypeText, MessageID: 12, From: "peer-b", To: "peer-a"},
+		{TsUnixNano: 230, Event: EventATXSoftware, MessageType: protocol.MessageTypeText, MessageID: 12, From: "peer-b", To: "peer-a"},
+		{TsUnixNano: 310, Event: EventBAppRecv, MessageType: protocol.MessageTypeText, MessageID: 12, From: "peer-b", To: "peer-a"},
+	}
+
+	summaries := SummarizeEvents(events)
+	if len(summaries) != 4 {
+		t.Fatalf("summary count = %d, want 4", len(summaries))
+	}
+
+	gotByMessageID := make(map[uint64]Summary, len(summaries))
+	for _, summary := range summaries {
+		gotByMessageID[summary.MessageID] = summary
+	}
+
+	if got := ptrValue(gotByMessageID[1].ApproxRTTNS); got != 150 {
+		t.Fatalf("message 1 ApproxRTTNS = %d, want 150", got)
+	}
+	if got := ptrValue(gotByMessageID[2].ApproxRTTNS); got != 170 {
+		t.Fatalf("message 2 ApproxRTTNS = %d, want 170", got)
+	}
+	if gotByMessageID[11].ApproxRTTNS != nil {
+		t.Fatalf("message 11 ApproxRTTNS = %d, want nil", ptrValue(gotByMessageID[11].ApproxRTTNS))
+	}
+	if gotByMessageID[12].ApproxRTTNS != nil {
+		t.Fatalf("message 12 ApproxRTTNS = %d, want nil", ptrValue(gotByMessageID[12].ApproxRTTNS))
+	}
+}
+
 func TestSummarizeEventsReportsMissingTimestamps(t *testing.T) {
 	events := []Event{
 		{TsUnixNano: 100, Event: EventAAppPrepBegin, MessageType: protocol.MessageTypeText, MessageID: 2, From: "peer-a", To: "peer-b"},
diff --git a/cmd/internal/peer/client.go b/cmd/internal/peer/client.go
index 48cb5fa..8ab0dd8 100644
--- a/cmd/internal/peer/client.go
+++ b/cmd/internal/peer/client.go
@@ -195,6 +195,7 @@ func (c *Client) nextMessageID() uint64 {
 	return atomic.AddUint64(&c.nextID, 1)
 }
 
+// 根据提供的选项创建 TCP 连接，并进行必要的配置，例如绑定本地 IP 或网卡。成功建立连接后，返回一个封装了该连接的 TCPConn 实例。
 func dialServerWithOptions(serverAddr string, options clientOptions) (net.Conn, error) {
 	dialer, err := buildDialer(options)
 	if err != nil {