diff --git a/net/ping/ping.go b/net/ping/ping.go
index 4182d77..10abca5 100644
--- a/net/ping/ping.go
+++ b/net/ping/ping.go
@@ -6,41 +6,109 @@ import (
 	"strings"
 )
 
-type PingOptions struct {
-	Retry    int
-	Interval int
-	Deadline int
+type Option interface {
+	Retry() int
+	Interval() int
+	Deadline() int
+	Validate()
 }
 
-type Response struct {
-	TTL  int
-	Time float32
+type Response interface {
+	TTL() int
+	Time() float32
 }
 
-type Summary struct {
-	SendCount    int
-	ReceiveCount int
-	LossPercent  float32
-	MinTime      float32
-	MaxTime      float32
-	AvgTime      float32
+type Summary interface {
+	SendCount() int
+	ReceiveCount() int
+	LossPercent() float32
+	MinTime() float32
+	MaxTime() float32
+	AvgTime() float32
+}
+
+type Result interface {
+	Responses() map[int]Response
+	Summary() Summary
+}
+
+type PingOption struct {
+	retry    int
+	interval int
+	deadline int
+}
+
+func (o *PingOption) Retry() int {
+	return o.retry
+}
+func (o *PingOption) Interval() int {
+	return o.interval
+}
+func (o *PingOption) Deadline() int {
+	return o.deadline
+}
+func (o *PingOption) Validate() {
+	if 0 >= o.retry {
+		o.retry = 1
+	}
+	if 0 >= o.interval {
+		o.interval = 1
+	}
+	if 0 >= o.deadline {
+		o.deadline = 1
+	}
+}
+
+type PingResponse struct {
+	ttl  int
+	time float32
+}
+
+func (r *PingResponse) TTL() int {
+	return r.ttl
+}
+func (r *PingResponse) Time() float32 {
+	return r.time
+}
+
+type PingSummary struct {
+	sendCount    int
+	receiveCount int
+	lossPercent  float32
+	minTime      float32
+	maxTime      float32
+	avgTime      float32
+}
+
+func (s *PingSummary) SendCount() int {
+	return s.sendCount
+}
+func (s *PingSummary) ReceiveCount() int {
+	return s.receiveCount
+}
+func (s *PingSummary) LossPercent() float32 {
+	return s.lossPercent
+}
+func (s *PingSummary) MinTime() float32 {
+	return s.minTime
+}
+func (s *PingSummary) MaxTime() float32 {
+	return s.maxTime
+}
+func (s *PingSummary) AvgTime() float32 {
+	return s.avgTime
 }
 
 type PingResult struct {
-	Responses map[int]*Response
-	Summary   *Summary
+	responses map[int]Response
+	summary   Summary
 }
 
-func (o *PingOptions) Validate() {
-	if 0 >= o.Retry {
-		o.Retry = 1
-	}
-	if 0 >= o.Interval {
-		o.Interval = 1
-	}
-	if 0 >= o.Deadline {
-		o.Deadline = 1
-	}
+func (r *PingResult) Responses() map[int]Response {
+	return r.responses
+}
+func (r *PingResult) Summary() Summary {
+	return r.summary
 }
 
 // $ ping 192.168.1.1 -c 7 -i 1 -w 0.3
@@ -54,10 +122,10 @@ func (o *PingOptions) Validate() {
 // --- 192.168.1.1 ping statistics ---
 // 7 packets transmitted, 4 received, 42% packet loss, time 6010ms
 // rtt min/avg/max/mdev = 0.163/0.253/0.344/0.082 ms
-func parseLinuxPing(output []byte) (*PingResult, error) {
+func parseLinuxPing(output []byte) (Result, error) {
 	result := &PingResult{
-		Responses: make(map[int]*Response, 0),
-		Summary:   &Summary{},
+		responses: make(map[int]Response, 0),
+		summary:   &PingSummary{},
 	}
 	lines := strings.Split(string(output), "\n")
 
@@ -77,21 +145,21 @@ LOOP:
 				log.Print(err)
 				continue LOOP
 			}
-			result.Summary.MinTime = float32(minTime)
+			result.summary.(*PingSummary).minTime = float32(minTime)
 
 			maxTime, err := strconv.ParseFloat(times[2], 32)
 			if nil != err {
 				log.Print(err)
 				continue LOOP
 			}
-			result.Summary.MaxTime = float32(maxTime)
+			result.summary.(*PingSummary).maxTime = float32(maxTime)
 
 			avgTime, err := strconv.ParseFloat(times[1], 32)
 			if nil != err {
 				log.Print(err)
 				continue LOOP
 			}
-			result.Summary.AvgTime = float32(avgTime)
+			result.summary.(*PingSummary).avgTime = float32(avgTime)
 
 		case 8:
 			if "bytes" != fields[1] || "from" != fields[2] {
@@ -117,9 +185,9 @@ LOOP:
 				continue LOOP
 			}
 
-			result.Responses[seq] = &Response{
-				TTL:  ttl,
-				Time: float32(_time),
+			result.responses[seq] = &PingResponse{
+				ttl:  ttl,
+				time: float32(_time),
 			}
 
 		case 10:
@@ -128,21 +196,21 @@ LOOP:
 				log.Print(err)
 				continue LOOP
 			}
-			result.Summary.SendCount = sendCount
+			result.summary.(*PingSummary).sendCount = sendCount
 
 			receiveCount, err := strconv.Atoi(fields[3])
 			if nil != err {
 				log.Print(err)
 				continue LOOP
 			}
-			result.Summary.ReceiveCount = receiveCount
+			result.summary.(*PingSummary).receiveCount = receiveCount
 
 			lossPercent, err := strconv.ParseFloat(strings.Replace(fields[5], "%", "", -1), 32)
 			if nil != err {
 				log.Print(err)
 				continue LOOP
 			}
-			result.Summary.LossPercent = float32(lossPercent)
+			result.summary.(*PingSummary).lossPercent = float32(lossPercent)
 		}
 	}
 
@@ -178,10 +246,10 @@ LOOP:
 // Approximate round trip times in milli-seconds:
 //     Minimum = 37ms, Maximum = 38ms, Average = 37ms
 
-func parseWindowsPing(output []byte) (*PingResult, error) {
+func parseWindowsPing(output []byte) (Result, error) {
 	result := &PingResult{
-		Responses: make(map[int]*Response, 0),
-		Summary:   &Summary{},
+		responses: make(map[int]Response, 0),
+		summary:   &PingSummary{},
 	}
 	lines := strings.Split(string(output), "\n")
 
@@ -218,9 +286,9 @@ LOOP:
 				continue LOOP
 			}
 
-			result.Responses[seq] = &Response{
-				TTL:  ttl,
-				Time: float32(_time),
+			result.responses[seq] = &PingResponse{
+				ttl:  ttl,
+				time: float32(_time),
 			}
 			seq = seq + 1
 		case 9:
@@ -235,7 +303,7 @@ LOOP:
 				log.Print(err)
 				continue LOOP
 			}
-			result.Summary.MinTime = float32(minTime)
+			result.summary.(*PingSummary).minTime = float32(minTime)
 
 			maxTimes := strings.Replace(fields[5], "ms", "", -1)
 			maxTimes = strings.Replace(maxTimes, ",", "", -1)
@@ -244,7 +312,7 @@ LOOP:
 				log.Print(err)
 				continue LOOP
 			}
-			result.Summary.MaxTime = float32(maxTime)
+			result.summary.(*PingSummary).maxTime = float32(maxTime)
 
 			avgTimes := strings.Replace(fields[8], "ms", "", -1)
 			avgTime, err := strconv.ParseFloat(avgTimes, 32)
@@ -252,7 +320,7 @@ LOOP:
 				log.Print(err)
 				continue LOOP
 			}
-			result.Summary.AvgTime = float32(avgTime)
+			result.summary.(*PingSummary).avgTime = float32(avgTime)
 
 		case 12:
 			if "Packets:" != fields[0] {
@@ -263,14 +331,14 @@ LOOP:
 				log.Print(err)
 				continue LOOP
 			}
-			result.Summary.SendCount = sendCount
+			result.summary.(*PingSummary).sendCount = sendCount
 
 			receiveCount, err := strconv.Atoi(strings.Replace(fields[6], ",", "", -1))
 			if nil != err {
 				log.Print(err)
 				continue LOOP
 			}
-			result.Summary.ReceiveCount = receiveCount
+			result.summary.(*PingSummary).receiveCount = receiveCount
 
 			lossPercents := strings.Replace(fields[10], "(", "", -1)
 			lossPercents = strings.Replace(lossPercents, "%", "", -1)
@@ -279,7 +347,7 @@ LOOP:
 				log.Print(err)
 				continue LOOP
 			}
-			result.Summary.LossPercent = float32(lossPercent)
+			result.summary.(*PingSummary).lossPercent = float32(lossPercent)
 		}
 	}
 
@@ -297,10 +365,10 @@ LOOP:
 // --- 192.168.1.1 ping statistics ---
 // 5 packets transmitted, 5 packets received, 0.0% packet loss
 // round-trip min/avg/max/stddev = 0.971/2.760/3.934/1.204 ms
-func parseDarwinPing(output []byte) (*PingResult, error) {
+func parseDarwinPing(output []byte) (Result, error) {
 	result := &PingResult{
-		Responses: make(map[int]*Response, 0),
-		Summary:   &Summary{},
+		responses: make(map[int]Response, 0),
+		summary:   &PingSummary{},
 	}
 	lines := strings.Split(string(output), "\n")
 
@@ -320,21 +388,21 @@ LOOP:
 				log.Print(err)
 				continue LOOP
 			}
-			result.Summary.MinTime = float32(minTime)
+			result.summary.(*PingSummary).minTime = float32(minTime)
 
 			maxTime, err := strconv.ParseFloat(times[2], 32)
 			if nil != err {
 				log.Print(err)
 				continue LOOP
 			}
-			result.Summary.MaxTime = float32(maxTime)
+			result.summary.(*PingSummary).maxTime = float32(maxTime)
 
 			avgTime, err := strconv.ParseFloat(times[1], 32)
 			if nil != err {
 				log.Print(err)
 				continue LOOP
 			}
-			result.Summary.AvgTime = float32(avgTime)
+			result.summary.(*PingSummary).avgTime = float32(avgTime)
 
 		case 8:
 			if "bytes" != fields[1] || "from" != fields[2] {
@@ -360,9 +428,9 @@ LOOP:
 				continue LOOP
 			}
 
-			result.Responses[seq] = &Response{
-				TTL:  ttl,
-				Time: float32(_time),
+			result.responses[seq] = &PingResponse{
+				ttl:  ttl,
+				time: float32(_time),
 			}
 
 		case 9:
@@ -371,21 +439,21 @@ LOOP:
 				log.Print(err)
 				continue LOOP
 			}
-			result.Summary.SendCount = sendCount
+			result.summary.(*PingSummary).sendCount = sendCount
 
 			receiveCount, err := strconv.Atoi(fields[3])
 			if nil != err {
 				log.Print(err)
 				continue LOOP
 			}
-			result.Summary.ReceiveCount = receiveCount
+			result.summary.(*PingSummary).receiveCount = receiveCount
 
 			lossPercent, err := strconv.ParseFloat(strings.Replace(fields[6], "%", "", -1), 32)
 			if nil != err {
 				log.Print(err)
 				continue LOOP
 			}
-			result.Summary.LossPercent = float32(lossPercent)
+			result.summary.(*PingSummary).lossPercent = float32(lossPercent)
 		}
 	}
 
diff --git a/net/ping/ping_darwin.go b/net/ping/ping_darwin.go
index 124d030..ca91688 100644
--- a/net/ping/ping_darwin.go
+++ b/net/ping/ping_darwin.go
@@ -5,13 +5,13 @@ import (
 	"os/exec"
 )
 
-func Ping(destination string, options *PingOptions) (*PingResult, error) {
-	options.Validate()
+func Ping(destination string, options Option) (Result, error) {
+	option.Validate()
 
 	params := make([]string, 0)
 	params = append(params, destination)
-	params = append(params, fmt.Sprintf("-c %d", options.Retry))
-	params = append(params, fmt.Sprintf("-i %d", options.Interval))
+	params = append(params, fmt.Sprintf("-c %d", option.Retry()))
+	params = append(params, fmt.Sprintf("-i %d", option.Interval()))
 
 	pCmd := exec.Command("ping", params...)
 	output, err := pCmd.CombinedOutput()
diff --git a/net/ping/ping_darwin_test.go b/net/ping/ping_darwin_test.go
index b4deece..e9d8cf9 100644
--- a/net/ping/ping_darwin_test.go
+++ b/net/ping/ping_darwin_test.go
@@ -8,27 +8,27 @@ import (
 func TestPing(t *testing.T) {
 	type args struct {
 		destination string
-		options     *PingOptions
+		option      Option
 	}
 	tests := []struct {
 		name    string
 		args    args
-		want    *PingResult
+		want    Result
 		wantErr bool
 	}{
 		{
 			name: "192.168.1.1",
 			args: args{
 				destination: "192.168.1.1",
-				options: &PingOptions{
-					Retry: 4,
+				option: &PingOption{
+					retry: 4,
 				},
 			},
 		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			got, err := Ping(tt.args.destination, tt.args.options)
+			got, err := Ping(tt.args.destination, tt.args.option)
 			if (err != nil) != tt.wantErr {
 				t.Errorf("Ping() error = %v, wantErr %v", err, tt.wantErr)
 				return
diff --git a/net/ping/ping_linux.go b/net/ping/ping_linux.go
index 1578270..5f79380 100644
--- a/net/ping/ping_linux.go
+++ b/net/ping/ping_linux.go
@@ -2,21 +2,23 @@ package ping
 
 import (
 	"fmt"
+	"log"
 	"os/exec"
 )
 
-func Ping(destination string, options *PingOptions) (*PingResult, error) {
-	options.Validate()
+func Ping(destination string, option Option) (Result, error) {
+	option.Validate()
 
 	params := make([]string, 0)
 	params = append(params, destination)
-	params = append(params, fmt.Sprintf("-c %d", options.Retry))
-	params = append(params, fmt.Sprintf("-i %d", options.Interval))
-	params = append(params, fmt.Sprintf("-w %d", options.Deadline))
+	params = append(params, fmt.Sprintf("-c %d", option.Retry()))
+	params = append(params, fmt.Sprintf("-i %d", option.Interval()))
 
 	pCmd := exec.Command("ping", params...)
+	log.Print(pCmd.Args)
 	output, err := pCmd.CombinedOutput()
 	if err != nil {
+		log.Print(err)
 		return nil, err
 	}
 
diff --git a/net/ping/ping_linux_test.go b/net/ping/ping_linux_test.go
index 4ea5306..516017a 100644
--- a/net/ping/ping_linux_test.go
+++ b/net/ping/ping_linux_test.go
@@ -5,27 +5,27 @@ import "testing"
 func TestPing(t *testing.T) {
 	type args struct {
 		destination string
-		options     *PingOptions
+		option      Option
 	}
 	tests := []struct {
 		name    string
 		args    args
-		want    *PingResult
+		want    Result
 		wantErr bool
 	}{
 		{
 			name: "192.168.1.1",
 			args: args{
 				destination: "192.168.1.1",
-				options: &PingOptions{
-					Retry: 4,
+				option: &PingOption{
+					retry: 4,
 				},
 			},
 		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			got, err := Ping(tt.args.destination, tt.args.options)
+			got, err := Ping(tt.args.destination, tt.args.option)
 			if (err != nil) != tt.wantErr {
 				t.Errorf("Ping() error = %v, wantErr %v", err, tt.wantErr)
 				return
diff --git a/net/ping/ping_test.go b/net/ping/ping_test.go
index 366c70b..0240849 100644
--- a/net/ping/ping_test.go
+++ b/net/ping/ping_test.go
@@ -17,12 +17,13 @@ func TestPingOptions_Validate(t *testing.T) {
 	}{
 		// TODO: Add test cases.
 	}
+
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			o := &PingOptions{
-				Retry:    tt.fields.Retry,
-				Interval: tt.fields.Interval,
-				Deadline: tt.fields.Deadline,
+			o := &PingOption{
+				retry:    tt.fields.Retry,
+				interval: tt.fields.Interval,
+				deadline: tt.fields.Deadline,
 			}
 			o.Validate()
 		})
@@ -62,7 +63,7 @@ func Test_parseWindowsPing(t *testing.T) {
 	tests := []struct {
 		name    string
 		args    args
-		want    *PingResult
+		want    Result
 		wantErr bool
 	}{
 		{
@@ -108,7 +109,7 @@ func Test_parseDarwinPing(t *testing.T) {
 	tests := []struct {
 		name    string
 		args    args
-		want    *PingResult
+		want    Result
 		wantErr bool
 	}{
 		{
diff --git a/net/ping/ping_windows.go b/net/ping/ping_windows.go
index 6f8e605..fb89cbd 100644
--- a/net/ping/ping_windows.go
+++ b/net/ping/ping_windows.go
@@ -5,12 +5,12 @@ import (
 	"os/exec"
 )
 
-func Ping(destination string, options *PingOptions) (*PingResult, error) {
-	options.Validate()
+func Ping(destination string, option Option) (Result, error) {
+	option.Validate()
 
 	params := make([]string, 0)
 	params = append(params, "/C")
-	params = append(params, fmt.Sprintf("chcp 437 && ping %s -n %d -w %d", destination, options.Retry, options.Deadline*1000))
+	params = append(params, fmt.Sprintf("chcp 437 && ping %s -n %d -w %d", destination, option.Retry(), option.Deadline()*1000))
 
 	pCmd := exec.Command("cmd.exe", params...)
 	output, err := pCmd.CombinedOutput()
diff --git a/net/ping/ping_windows_test.go b/net/ping/ping_windows_test.go
index 4ea5306..516017a 100644
--- a/net/ping/ping_windows_test.go
+++ b/net/ping/ping_windows_test.go
@@ -5,27 +5,27 @@ import "testing"
 func TestPing(t *testing.T) {
 	type args struct {
 		destination string
-		options     *PingOptions
+		option      Option
 	}
 	tests := []struct {
 		name    string
 		args    args
-		want    *PingResult
+		want    Result
 		wantErr bool
 	}{
 		{
 			name: "192.168.1.1",
 			args: args{
 				destination: "192.168.1.1",
-				options: &PingOptions{
-					Retry: 4,
+				option: &PingOption{
+					retry: 4,
 				},
 			},
 		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			got, err := Ping(tt.args.destination, tt.args.options)
+			got, err := Ping(tt.args.destination, tt.args.option)
 			if (err != nil) != tt.wantErr {
 				t.Errorf("Ping() error = %v, wantErr %v", err, tt.wantErr)
 				return