diff --git a/go.mod b/go.mod
index 267c8648794..b7ffb7d3a9e 100644
--- a/go.mod
+++ b/go.mod
@@ -6,7 +6,7 @@ require (
 	cloud.google.com/go/compute v1.7.0
 	github.com/google/go-cmp v0.5.8
 	github.com/google/uuid v1.3.0
-	github.com/googleapis/enterprise-certificate-proxy v0.1.0
+	github.com/googleapis/enterprise-certificate-proxy v0.2.0
 	github.com/googleapis/gax-go/v2 v2.4.0
 	go.opencensus.io v0.23.0
 	golang.org/x/net v0.0.0-20220909164309-bea034e7d591
diff --git a/go.sum b/go.sum
index 7fb35d0a192..4b3eb0c492a 100644
--- a/go.sum
+++ b/go.sum
@@ -164,8 +164,8 @@ github.com/google/uuid v1.1.2/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+
 github.com/google/uuid v1.3.0 h1:t6JiXgmwXMjEs8VusXIJk2BXHsn+wx8BZdTaoZ5fu7I=
 github.com/google/uuid v1.3.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/googleapis/enterprise-certificate-proxy v0.0.0-20220520183353-fd19c99a87aa/go.mod h1:17drOmN3MwGY7t0e+Ei9b45FFGA3fBs3x36SsCg1hq8=
-github.com/googleapis/enterprise-certificate-proxy v0.1.0 h1:zO8WHNx/MYiAKJ3d5spxZXZE6KHmIQGQcAzwUzV7qQw=
-github.com/googleapis/enterprise-certificate-proxy v0.1.0/go.mod h1:17drOmN3MwGY7t0e+Ei9b45FFGA3fBs3x36SsCg1hq8=
+github.com/googleapis/enterprise-certificate-proxy v0.2.0 h1:y8Yozv7SZtlU//QXbezB6QkpuE6jMD2/gfzk4AftXjs=
+github.com/googleapis/enterprise-certificate-proxy v0.2.0/go.mod h1:8C0jb7/mgJe/9KK8Lm7X9ctZC2t60YyIpYEI16jx0Qg=
 github.com/googleapis/gax-go/v2 v2.0.4/go.mod h1:0Wqv26UfaUD9n4G6kQubkQ+KchISgw+vpHVxEJEs9eg=
 github.com/googleapis/gax-go/v2 v2.0.5/go.mod h1:DWXyrwAJ9X0FpwwEdw+IPEYBICEFu5mhpdKc/us6bOk=
 github.com/googleapis/gax-go/v2 v2.1.0/go.mod h1:Q3nei7sK6ybPYH7twZdmQpAd1MKb7pfu6SK+H1/DsU0=
diff --git a/transport/cert/enterprise_cert_test.go b/transport/cert/enterprise_cert_test.go
index 8f20887fd70..f3a539b2f6d 100644
--- a/transport/cert/enterprise_cert_test.go
+++ b/transport/cert/enterprise_cert_test.go
@@ -20,7 +20,7 @@ func TestEnterpriseCertificateProxySource_ConfigMissing(t *testing.T) {
 
 // This test launches a mock signer binary "test_signer.go" that uses a valid pem file.
 func TestEnterpriseCertificateProxySource_GetClientCertificateSuccess(t *testing.T) {
-	source, err := NewEnterpriseCertificateProxySource("testdata/enterprise_certificate_config.json")
+	source, err := NewEnterpriseCertificateProxySource("testdata/certificate_config.json")
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -38,7 +38,7 @@ func TestEnterpriseCertificateProxySource_GetClientCertificateSuccess(t *testing
 
 // This test launches a mock signer binary "test_signer.go" that uses an invalid pem file.
 func TestEnterpriseCertificateProxySource_InitializationFailure(t *testing.T) {
-	_, err := NewEnterpriseCertificateProxySource("testdata/enterprise_certificate_config_invalid_pem.json")
+	_, err := NewEnterpriseCertificateProxySource("testdata/certificate_config_invalid_pem.json")
 	if err == nil {
 		t.Error("NewEnterpriseCertificateProxySource: got nil, want non-nil err")
 	}
diff --git a/transport/cert/testdata/certificate_config.json b/transport/cert/testdata/certificate_config.json
new file mode 100644
index 00000000000..89523d44d9c
--- /dev/null
+++ b/transport/cert/testdata/certificate_config.json
@@ -0,0 +1,10 @@
+{
+  "cert_configs": {
+    "test": {
+      "issuer": "Test Issuer"
+    }
+  },
+  "libs": {
+    "ecp": "./testdata/signer.sh"
+  }
+}
diff --git a/transport/cert/testdata/certificate_config_invalid_pem.json b/transport/cert/testdata/certificate_config_invalid_pem.json
new file mode 100644
index 00000000000..d56afa40b02
--- /dev/null
+++ b/transport/cert/testdata/certificate_config_invalid_pem.json
@@ -0,0 +1,10 @@
+{
+  "cert_configs": {
+    "test": {
+      "issuer": "Test Issuer"
+    }
+  },
+  "libs": {
+    "ecp": "./testdata/signer_invalid_pem.sh"
+  }
+}
diff --git a/transport/cert/testdata/enterprise_certificate_config.json b/transport/cert/testdata/enterprise_certificate_config.json
deleted file mode 100644
index be9f9a3e806..00000000000
--- a/transport/cert/testdata/enterprise_certificate_config.json
+++ /dev/null
@@ -1,8 +0,0 @@
-{
-  "cert_info": {
-    "issuer": "Test Issuer"
-  },
-  "libs": {
-    "signer_binary": "./testdata/signer.sh"
-  }
-}
diff --git a/transport/cert/testdata/enterprise_certificate_config_invalid_pem.json b/transport/cert/testdata/enterprise_certificate_config_invalid_pem.json
deleted file mode 100644
index 5fc2dcfc8f9..00000000000
--- a/transport/cert/testdata/enterprise_certificate_config_invalid_pem.json
+++ /dev/null
@@ -1,8 +0,0 @@
-{
-  "cert_info": {
-    "issuer": "Test Issuer"
-  },
-  "libs": {
-    "signer_binary": "./testdata/signer_invalid_pem.sh"
-  }
-}
diff --git a/transport/cert/testdata/rsa2048bit.pem b/transport/cert/testdata/rsa2048bit.pem
new file mode 100644
index 00000000000..91ebda969a2
--- /dev/null
+++ b/transport/cert/testdata/rsa2048bit.pem
@@ -0,0 +1,49 @@
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----
+-----BEGIN PRIVATE KEY-----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+-----END PRIVATE KEY-----
\ No newline at end of file
diff --git a/transport/cert/testdata/signer.sh b/transport/cert/testdata/signer.sh
index 8a7b2192526..6b4fb6cd960 100755
--- a/transport/cert/testdata/signer.sh
+++ b/transport/cert/testdata/signer.sh
@@ -4,4 +4,4 @@
 # Use of this source code is governed by a BSD-style
 # license that can be found in the LICENSE file.
 
-go run ../internal/ecp/test_signer.go testdata/testcert.pem
+go run ../internal/ecp/test_signer.go testdata/rsa2048bit.pem