diff --git a/test/e2e/network/dns.go b/test/e2e/network/dns.go
index c4efcba442a..a07aa0f77f8 100644
--- a/test/e2e/network/dns.go
+++ b/test/e2e/network/dns.go
@@ -202,7 +202,7 @@ var _ = SIGDescribe("DNS", func() {
 		_, err = framework.UpdateService(f.ClientSet, f.Namespace.Name, serviceName, func(s *v1.Service) {
 			s.Spec.Type = v1.ServiceTypeClusterIP
 			s.Spec.Ports = []v1.ServicePort{
-				{Port: 80, Name: "http", Protocol: "TCP"},
+				{Port: 80, Name: "http", Protocol: v1.ProtocolTCP},
 			}
 		})
 		Expect(err).NotTo(HaveOccurred())
diff --git a/test/e2e/network/dns_common.go b/test/e2e/network/dns_common.go
index 9a6c2a66811..e910626bbc4 100644
--- a/test/e2e/network/dns_common.go
+++ b/test/e2e/network/dns_common.go
@@ -213,7 +213,7 @@ func (t *dnsTestCommon) createUtilPodLabel(baseName string) {
 					Image:   imageutils.GetE2EImage(imageutils.Dnsutils),
 					Command: []string{"sleep", "10000"},
 					Ports: []v1.ContainerPort{
-						{ContainerPort: servicePort, Protocol: "TCP"},
+						{ContainerPort: servicePort, Protocol: v1.ProtocolTCP},
 					},
 				},
 			},
@@ -238,7 +238,7 @@ func (t *dnsTestCommon) createUtilPodLabel(baseName string) {
 			Selector: map[string]string{"app": baseName},
 			Ports: []v1.ServicePort{
 				{
-					Protocol:   "TCP",
+					Protocol:   v1.ProtocolTCP,
 					Port:       servicePort,
 					TargetPort: intstr.FromInt(servicePort),
 				},
diff --git a/test/e2e/network/firewall.go b/test/e2e/network/firewall.go
index 01616295d78..f665ff3c6d1 100644
--- a/test/e2e/network/firewall.go
+++ b/test/e2e/network/firewall.go
@@ -70,7 +70,7 @@ var _ = SIGDescribe("Firewall rule", func() {
 
 		By("Creating a LoadBalancer type service with ExternalTrafficPolicy=Global")
 		svc := jig.CreateLoadBalancerService(ns, serviceName, framework.LoadBalancerCreateTimeoutDefault, func(svc *v1.Service) {
-			svc.Spec.Ports = []v1.ServicePort{{Protocol: "TCP", Port: framework.FirewallTestHttpPort}}
+			svc.Spec.Ports = []v1.ServicePort{{Protocol: v1.ProtocolTCP, Port: framework.FirewallTestHttpPort}}
 			svc.Spec.LoadBalancerSourceRanges = firewallTestSourceRanges
 		})
 		defer func() {
diff --git a/test/e2e/network/service.go b/test/e2e/network/service.go
index e9a05abf243..acfaae982d2 100644
--- a/test/e2e/network/service.go
+++ b/test/e2e/network/service.go
@@ -57,7 +57,7 @@ var (
 			Ports: []v1.ServicePort{{
 				Port:       int32(defaultServeHostnameServicePort),
 				TargetPort: intstr.FromInt(9376),
-				Protocol:   "TCP",
+				Protocol:   v1.ProtocolTCP,
 			}},
 			Selector: map[string]string{
 				"name": defaultServeHostnameServiceName,
@@ -897,7 +897,7 @@ var _ = SIGDescribe("Services", func() {
 			s.Spec.Type = v1.ServiceTypeClusterIP
 			s.Spec.ExternalName = ""
 			s.Spec.Ports = []v1.ServicePort{
-				{Port: 80, Name: "http", Protocol: "TCP"},
+				{Port: 80, Name: "http", Protocol: v1.ProtocolTCP},
 			}
 		})
 		jig.SanityCheckService(clusterIPService, v1.ServiceTypeClusterIP)
@@ -921,7 +921,7 @@ var _ = SIGDescribe("Services", func() {
 			s.Spec.Type = v1.ServiceTypeNodePort
 			s.Spec.ExternalName = ""
 			s.Spec.Ports = []v1.ServicePort{
-				{Port: 80, Name: "http", Protocol: "TCP"},
+				{Port: 80, Name: "http", Protocol: v1.ProtocolTCP},
 			}
 		})
 		jig.SanityCheckService(nodePortService, v1.ServiceTypeNodePort)