diff --git a/token-validator/challenge.go b/token-validator/challenge.go
index e3ed15f..dcec5b9 100644
--- a/token-validator/challenge.go
+++ b/token-validator/challenge.go
@@ -112,6 +112,31 @@ func challengeTime(s *Student, t *givenToken, chid int) error {
 	}
 }
 
+func challengePing(s *Student, t *givenToken, chid int) error {
+	var expected []byte
+	switch s.Id % 5 {
+	case 1:
+		expected = []byte("baaaaaad")
+	case 2:
+		expected = []byte("baadfood")
+	case 3:
+		expected = []byte("baddcafe")
+	case 4:
+		expected = []byte("cafebabe")
+	default:
+		expected = []byte("deadbeef")
+	}
+
+	pkey := s.GetPKey()
+	if expectedToken, err := GenerateToken(pkey, chid, expected); err != nil {
+		return err
+	} else if ! hmac.Equal(expectedToken, t.token) {
+		return errors.New("This is not the expected token.")
+	} else {
+		return nil
+	}
+}
+
 func challengeDisk(s *Student, t *givenToken, chid int) error {
 	pkey := fmt.Sprintf("%x", s.GetPKey())
 
@@ -164,28 +189,37 @@ func init() {
 			Check: challengeTime,
 		},
 
-		/* Challenge 4 : disk */
-		Challenge{
-			Accessible: []func(*Student, *http.Request) error{noAccessRestriction},
-			Check: challengeDisk,
-		},
-
-		/* Challenge 5 : DNS TXT */
+		/* Challenge 4 : DNS TXT */
 		Challenge{
 			Accessible: []func(*Student, *http.Request) error{accessFrom(IPgwDMZ), sslOnly},
 			Check: challengeDNS,
 		},
 
-		/* Challenge 6 : time net */
+		/* Challenge 5 : time net */
 		Challenge{
 			Accessible: []func(*Student, *http.Request) error{maxProxy(1)},
 			Check: challengeTime,
 		},
+
+		/* Bonus 1 : echo request */
+		Challenge{
+			Accessible: []func(*Student, *http.Request) error{noAccessRestriction},
+			Check: challengePing,
+		},
+
+		/* Bonus 2 : disk */
+		Challenge{
+			Accessible: []func(*Student, *http.Request) error{noAccessRestriction},
+			Check: challengeDisk,
+		},
+
 	}
 
 	router.GET("/challenge", apiHandler(getChallengeList))
 	router.GET("/challenge/:chid", rawHandler(accessibleChallenge))
-	router.POST("/challenge", rawHandler(receiveToken))
+	router.POST("/challenge", rawHandler(challengeHandler(receiveToken)))
+	router.POST("/echorequest", rawHandler(definedChallengeHandler(receiveToken, 6)))
+	router.POST("/testdisk", rawHandler(definedChallengeHandler(receiveToken, 7)))
 }
 
 type givenToken struct {
@@ -219,7 +253,7 @@ func accessibleChallenge(r *http.Request, ps httprouter.Params, _ []byte) (inter
 	}
 }
 
-func receiveToken(r *http.Request, ps httprouter.Params, body []byte) (interface{}, error) {
+func receiveToken(r *http.Request, body []byte, chid int) (interface{}, error) {
 	var gt givenToken
 	if err := json.Unmarshal(body, &gt); err != nil {
 		return nil, err
@@ -231,22 +265,11 @@ func receiveToken(r *http.Request, ps httprouter.Params, body []byte) (interface
 	}
 
 	// Find challenge ID
-	var chid int
-	var err error
-	if chid, err = strconv.Atoi(string(ps.ByName("chid"))); err != nil {
-		if gt.Challenge > 0 {
-			chid = gt.Challenge
-		} else if string(ps.ByName("chid")) != "" {
-			return nil, err
-		}
-		err = nil
+	if gt.Challenge >= 1 {
+		chid = gt.Challenge
 	}
 
-	if chid == 0 {
-		chid = 4
-	}
-
-	if chid > len(challenges) {
+	if chid <= 0 || chid - 1 > len(challenges) {
 		return nil, errors.New("This challenge doesn't exist")
 	}
 
diff --git a/token-validator/handler.go b/token-validator/handler.go
index e4edab0..1fa7b32 100644
--- a/token-validator/handler.go
+++ b/token-validator/handler.go
@@ -107,6 +107,18 @@ func rawHandler(f func(*http.Request, httprouter.Params, []byte) (interface{}, e
 	}
 }
 
+func challengeHandler(f func (*http.Request, []byte, int) (interface{}, error)) func(*http.Request, httprouter.Params, []byte) (interface{}, error) {
+	return func(r *http.Request, ps httprouter.Params, body []byte) (interface{}, error) {
+		return f(r, body, 0)
+	}
+}
+
+func definedChallengeHandler(f func (*http.Request, []byte, int) (interface{}, error), chid int) func(*http.Request, httprouter.Params, []byte) (interface{}, error) {
+	return func(r *http.Request, ps httprouter.Params, body []byte) (interface{}, error) {
+		return f(r, body, chid)
+	}
+}
+
 func apiHandler(f DispatchFunction, access ...func(*Student, *http.Request) error) func(http.ResponseWriter, *http.Request, httprouter.Params) {
 	return rawHandler(func (_ *http.Request, ps httprouter.Params, b []byte) (interface{}, error) { return f(ps, b) }, access...)
 }
diff --git a/token-validator/ip.go b/token-validator/ip.go
index aa058b7..598e376 100644
--- a/token-validator/ip.go
+++ b/token-validator/ip.go
@@ -24,10 +24,13 @@ func showIPs(_ httprouter.Params, body []byte) (interface{}, error) {
 	}
 
 	for _, std := range students {
-		r[std.Login] = make(map[string]string)
+		sid := fmt.Sprintf("%d", std.Id)
 
-		r[std.Login]["vlan0"] = fmt.Sprintf("172.23.0.%d", std.IPSuffix())
-		r[std.Login]["vlan7"] = fmt.Sprintf("172.23.142.%d", std.IPSuffix())
+		r[sid] = make(map[string]string)
+
+		r[sid]["mac"] = std.MAC
+		r[sid]["vlan0"] = fmt.Sprintf("172.23.0.%d", std.IPSuffix())
+		r[sid]["vlan7"] = fmt.Sprintf("172.23.142.%d", std.IPSuffix())
 	}
 
 	return r, nil
diff --git a/token-validator/ping.go b/token-validator/ping.go
index 3c6fea1..5b096ab 100644
--- a/token-validator/ping.go
+++ b/token-validator/ping.go
@@ -1,14 +1,63 @@
 package main
 
 import (
+	"encoding/json"
+	"errors"
 	"time"
 )
 
+var PongSecret = "felixfixit"
+
 func init() {
+	router.GET("/api/students/:sid/ping", apiHandler(studentHandler(isPinging)))
+	router.GET("/api/students/:sid/pong", apiHandler(studentHandler(func (student Student, body []byte) (interface{}, error) {
+		return student.lastPongs()
+	})))
 	router.POST("/api/students/:sid/pong", apiHandler(studentHandler(stdPong), sslOnly))
 }
 
+func isPinging(student Student, body []byte) (interface{}, error) {
+	if pongs, err := student.lastPongs(); err != nil {
+		return nil, err
+	} else if len(pongs) <= 0 {
+		return false, nil
+	} else {
+		return time.Now().Before(pongs[0].Add(time.Second * 10)), nil
+	}
+}
+
+func (s Student) lastPongs() (pongs []time.Time, err error) {
+	if rows, errr := DBQuery("SELECT time FROM student_pong WHERE id_student = ? ORDER BY time DESC", s.Id); errr != nil {
+		return nil, errr
+	} else {
+		defer rows.Close()
+
+		for rows.Next() {
+			var t time.Time
+			if err = rows.Scan(&t); err != nil {
+				return
+			}
+			pongs = append(pongs, t)
+		}
+		if err = rows.Err(); err != nil {
+			return
+		}
+
+		return
+	}
+}
+
 func stdPong(student Student, body []byte) (interface{}, error) {
+	var gt givenToken
+	if err := json.Unmarshal(body, &gt); err != nil {
+		return nil, err
+	}
+
+	if gt.Token != PongSecret {
+		return nil, errors.New("This is not the expected token.")
+	}
+
+
 	if res, err := DBExec("INSERT INTO student_pong (id_student, time) VALUES (?, ?)", student.Id, time.Now()); err != nil {
 		return false, err
 	} else if _, err := res.LastInsertId(); err != nil {
diff --git a/token-validator/students.go b/token-validator/students.go
index 45218a1..4ad3e4d 100644
--- a/token-validator/students.go
+++ b/token-validator/students.go
@@ -87,7 +87,7 @@ func getStudent(id int) (s Student, err error) {
 }
 
 func getStudentByLogin(login string) (s Student, err error) {
-	err = DBQueryRow("SELECT id_student, login, time FROM students WHERE login=?", login).Scan(&s.Id, &s.Login, &s.Time)
+	err = DBQueryRow("SELECT S.id_student, S.login, MAX(L.time), L.ip, L.mac FROM students S INNER JOIN (SELECT a.id_student, a.time, a.ip, a.mac FROM student_login a INNER JOIN (SELECT id_student, MAX(time) AS time FROM student_login GROUP BY id_student) b ON a.id_student = b.id_student AND a.time = b.time) L ON S.id_student = L.id_student WHERE login=?", login).Scan(&s.Id, &s.Login, &s.Time, &s.IP, &s.MAC)
 	return
 }
 
@@ -155,6 +155,9 @@ func createStudent(_ httprouter.Params, body []byte) (interface{}, error) {
 		}
 	}
 	exist.registerAccess(std.IP, std.MAC)
+
+	exist.IP = fmt.Sprintf("172.23.0.%d", exist.IPSuffix())
+
 	return exist, nil
 }