diff --git a/registry/client/authchallenge.go b/registry/client/authchallenge.go
index 0485f42d..f45704b1 100644
--- a/registry/client/authchallenge.go
+++ b/registry/client/authchallenge.go
@@ -127,7 +127,7 @@ func expectTokenOrQuoted(s string) (value string, rest string) {
 			p := make([]byte, len(s)-1)
 			j := copy(p, s[:i])
 			escape := true
-			for i = i + i; i < len(s); i++ {
+			for i = i + 1; i < len(s); i++ {
 				b := s[i]
 				switch {
 				case escape:
diff --git a/registry/client/authchallenge_test.go b/registry/client/authchallenge_test.go
new file mode 100644
index 00000000..bb3016ee
--- /dev/null
+++ b/registry/client/authchallenge_test.go
@@ -0,0 +1,37 @@
+package client
+
+import (
+	"net/http"
+	"testing"
+)
+
+func TestAuthChallengeParse(t *testing.T) {
+	header := http.Header{}
+	header.Add("WWW-Authenticate", `Bearer realm="https://auth.example.com/token",service="registry.example.com",other=fun,slashed="he\"\l\lo"`)
+
+	challenges := parseAuthHeader(header)
+	if len(challenges) != 1 {
+		t.Fatalf("Unexpected number of auth challenges: %d, expected 1", len(challenges))
+	}
+
+	if expected := "bearer"; challenges[0].Scheme != expected {
+		t.Fatalf("Unexpected scheme: %s, expected: %s", challenges[0].Scheme, expected)
+	}
+
+	if expected := "https://auth.example.com/token"; challenges[0].Parameters["realm"] != expected {
+		t.Fatalf("Unexpected param: %s, expected: %s", challenges[0].Parameters["realm"], expected)
+	}
+
+	if expected := "registry.example.com"; challenges[0].Parameters["service"] != expected {
+		t.Fatalf("Unexpected param: %s, expected: %s", challenges[0].Parameters["service"], expected)
+	}
+
+	if expected := "fun"; challenges[0].Parameters["other"] != expected {
+		t.Fatalf("Unexpected param: %s, expected: %s", challenges[0].Parameters["other"], expected)
+	}
+
+	if expected := "he\"llo"; challenges[0].Parameters["slashed"] != expected {
+		t.Fatalf("Unexpected param: %s, expected: %s", challenges[0].Parameters["slashed"], expected)
+	}
+
+}
diff --git a/registry/client/endpoint.go b/registry/client/endpoint.go
index 83d3d991..9889dc66 100644
--- a/registry/client/endpoint.go
+++ b/registry/client/endpoint.go
@@ -117,6 +117,8 @@ func (e *RepositoryEndpoint) URLBuilder() (*v2.URLBuilder, error) {
 
 // HTTPClient returns a new HTTP client configured for this endpoint
 func (e *RepositoryEndpoint) HTTPClient(name string) (*http.Client, error) {
+	// TODO(dmcgowan): create http.Transport
+
 	transport := &repositoryTransport{
 		Header: e.Header,
 	}
diff --git a/registry/client/endpoint_test.go b/registry/client/endpoint_test.go
new file mode 100644
index 00000000..42bdc357
--- /dev/null
+++ b/registry/client/endpoint_test.go
@@ -0,0 +1,259 @@
+package client
+
+import (
+	"encoding/base64"
+	"fmt"
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+	"testing"
+
+	"github.com/docker/distribution/testutil"
+)
+
+type testAuthenticationWrapper struct {
+	headers   http.Header
+	authCheck func(string) bool
+	next      http.Handler
+}
+
+func (w *testAuthenticationWrapper) ServeHTTP(rw http.ResponseWriter, r *http.Request) {
+	auth := r.Header.Get("Authorization")
+	if auth == "" || !w.authCheck(auth) {
+		h := rw.Header()
+		for k, values := range w.headers {
+			h[k] = values
+		}
+		rw.WriteHeader(http.StatusUnauthorized)
+		return
+	}
+	w.next.ServeHTTP(rw, r)
+}
+
+func testServerWithAuth(rrm testutil.RequestResponseMap, authenticate string, authCheck func(string) bool) (*RepositoryEndpoint, func()) {
+	h := testutil.NewHandler(rrm)
+	wrapper := &testAuthenticationWrapper{
+
+		headers: http.Header(map[string][]string{
+			"Docker-Distribution-API-Version": {"registry/2.0"},
+			"WWW-Authenticate":                {authenticate},
+		}),
+		authCheck: authCheck,
+		next:      h,
+	}
+
+	s := httptest.NewServer(wrapper)
+	e := RepositoryEndpoint{Endpoint: s.URL, Mirror: false}
+	return &e, s.Close
+}
+
+type testCredentialStore struct {
+	username string
+	password string
+}
+
+func (tcs *testCredentialStore) Basic(*url.URL) (string, string) {
+	return tcs.username, tcs.password
+}
+
+func TestEndpointAuthorizeToken(t *testing.T) {
+	service := "localhost.localdomain"
+	repo1 := "some/registry"
+	repo2 := "other/registry"
+	scope1 := fmt.Sprintf("repository:%s:pull,push", repo1)
+	scope2 := fmt.Sprintf("repository:%s:pull,push", repo2)
+
+	tokenMap := testutil.RequestResponseMap([]testutil.RequestResponseMapping{
+		{
+			Request: testutil.Request{
+				Method: "GET",
+				Route:  fmt.Sprintf("/token?scope=%s&service=%s", url.QueryEscape(scope1), service),
+			},
+			Response: testutil.Response{
+				StatusCode: http.StatusOK,
+				Body:       []byte(`{"token":"statictoken"}`),
+			},
+		},
+		{
+			Request: testutil.Request{
+				Method: "GET",
+				Route:  fmt.Sprintf("/token?scope=%s&service=%s", url.QueryEscape(scope2), service),
+			},
+			Response: testutil.Response{
+				StatusCode: http.StatusOK,
+				Body:       []byte(`{"token":"badtoken"}`),
+			},
+		},
+	})
+	te, tc := testServer(tokenMap)
+	defer tc()
+
+	m := testutil.RequestResponseMap([]testutil.RequestResponseMapping{
+		{
+			Request: testutil.Request{
+				Method: "GET",
+				Route:  "/hello",
+			},
+			Response: testutil.Response{
+				StatusCode: http.StatusAccepted,
+			},
+		},
+	})
+
+	authenicate := fmt.Sprintf("Bearer realm=%q,service=%q", te.Endpoint+"/token", service)
+	validCheck := func(a string) bool {
+		return a == "Bearer statictoken"
+	}
+	e, c := testServerWithAuth(m, authenicate, validCheck)
+	defer c()
+
+	client, err := e.HTTPClient(repo1)
+	if err != nil {
+		t.Fatalf("Error creating http client: %s", err)
+	}
+
+	req, _ := http.NewRequest("GET", e.Endpoint+"/hello", nil)
+	resp, err := client.Do(req)
+	if err != nil {
+		t.Fatalf("Error sending get request: %s", err)
+	}
+
+	if resp.StatusCode != http.StatusAccepted {
+		t.Fatalf("Unexpected status code: %d, expected %d", resp.StatusCode, http.StatusAccepted)
+	}
+
+	badCheck := func(a string) bool {
+		return a == "Bearer statictoken"
+	}
+	e2, c2 := testServerWithAuth(m, authenicate, badCheck)
+	defer c2()
+
+	client2, err := e2.HTTPClient(repo2)
+	if err != nil {
+		t.Fatalf("Error creating http client: %s", err)
+	}
+
+	req, _ = http.NewRequest("GET", e.Endpoint+"/hello", nil)
+	resp, err = client2.Do(req)
+	if err != nil {
+		t.Fatalf("Error sending get request: %s", err)
+	}
+
+	if resp.StatusCode != http.StatusUnauthorized {
+		t.Fatalf("Unexpected status code: %d, expected %d", resp.StatusCode, http.StatusUnauthorized)
+	}
+}
+
+func basicAuth(username, password string) string {
+	auth := username + ":" + password
+	return base64.StdEncoding.EncodeToString([]byte(auth))
+}
+
+func TestEndpointAuthorizeTokenBasic(t *testing.T) {
+	service := "localhost.localdomain"
+	repo := "some/fun/registry"
+	scope := fmt.Sprintf("repository:%s:pull,push", repo)
+	username := "tokenuser"
+	password := "superSecretPa$$word"
+
+	tokenMap := testutil.RequestResponseMap([]testutil.RequestResponseMapping{
+		{
+			Request: testutil.Request{
+				Method: "GET",
+				Route:  fmt.Sprintf("/token?account=%s&scope=%s&service=%s", username, url.QueryEscape(scope), service),
+			},
+			Response: testutil.Response{
+				StatusCode: http.StatusOK,
+				Body:       []byte(`{"token":"statictoken"}`),
+			},
+		},
+	})
+
+	authenicate1 := fmt.Sprintf("Basic realm=localhost")
+	basicCheck := func(a string) bool {
+		return a == fmt.Sprintf("Basic %s", basicAuth(username, password))
+	}
+	te, tc := testServerWithAuth(tokenMap, authenicate1, basicCheck)
+	defer tc()
+
+	m := testutil.RequestResponseMap([]testutil.RequestResponseMapping{
+		{
+			Request: testutil.Request{
+				Method: "GET",
+				Route:  "/hello",
+			},
+			Response: testutil.Response{
+				StatusCode: http.StatusAccepted,
+			},
+		},
+	})
+
+	authenicate2 := fmt.Sprintf("Bearer realm=%q,service=%q", te.Endpoint+"/token", service)
+	bearerCheck := func(a string) bool {
+		return a == "Bearer statictoken"
+	}
+	e, c := testServerWithAuth(m, authenicate2, bearerCheck)
+	defer c()
+
+	e.Credentials = &testCredentialStore{
+		username: username,
+		password: password,
+	}
+
+	client, err := e.HTTPClient(repo)
+	if err != nil {
+		t.Fatalf("Error creating http client: %s", err)
+	}
+
+	req, _ := http.NewRequest("GET", e.Endpoint+"/hello", nil)
+	resp, err := client.Do(req)
+	if err != nil {
+		t.Fatalf("Error sending get request: %s", err)
+	}
+
+	if resp.StatusCode != http.StatusAccepted {
+		t.Fatalf("Unexpected status code: %d, expected %d", resp.StatusCode, http.StatusAccepted)
+	}
+}
+
+func TestEndpointAuthorizeBasic(t *testing.T) {
+	m := testutil.RequestResponseMap([]testutil.RequestResponseMapping{
+		{
+			Request: testutil.Request{
+				Method: "GET",
+				Route:  "/hello",
+			},
+			Response: testutil.Response{
+				StatusCode: http.StatusAccepted,
+			},
+		},
+	})
+
+	username := "user1"
+	password := "funSecretPa$$word"
+	authenicate := fmt.Sprintf("Basic realm=localhost")
+	validCheck := func(a string) bool {
+		return a == fmt.Sprintf("Basic %s", basicAuth(username, password))
+	}
+	e, c := testServerWithAuth(m, authenicate, validCheck)
+	defer c()
+	e.Credentials = &testCredentialStore{
+		username: username,
+		password: password,
+	}
+
+	client, err := e.HTTPClient("test/repo/basic")
+	if err != nil {
+		t.Fatalf("Error creating http client: %s", err)
+	}
+
+	req, _ := http.NewRequest("GET", e.Endpoint+"/hello", nil)
+	resp, err := client.Do(req)
+	if err != nil {
+		t.Fatalf("Error sending get request: %s", err)
+	}
+
+	if resp.StatusCode != http.StatusAccepted {
+		t.Fatalf("Unexpected status code: %d, expected %d", resp.StatusCode, http.StatusAccepted)
+	}
+}
diff --git a/registry/client/repository.go b/registry/client/repository.go
index a96390fa..578c3fca 100644
--- a/registry/client/repository.go
+++ b/registry/client/repository.go
@@ -25,8 +25,8 @@ import (
 	"golang.org/x/net/context"
 )
 
-// NewRepositoryClient creates a new Repository for the given repository name and endpoint
-func NewRepositoryClient(ctx context.Context, name string, endpoint *RepositoryEndpoint) (distribution.Repository, error) {
+// NewRepository creates a new Repository for the given repository name and endpoint
+func NewRepository(ctx context.Context, name string, endpoint *RepositoryEndpoint) (distribution.Repository, error) {
 	if err := v2.ValidateRespositoryName(name); err != nil {
 		return nil, err
 	}
diff --git a/registry/client/repository_test.go b/registry/client/repository_test.go
index 67138db6..b96c52e5 100644
--- a/registry/client/repository_test.go
+++ b/registry/client/repository_test.go
@@ -97,7 +97,7 @@ func TestLayerFetch(t *testing.T) {
 	e, c := testServer(m)
 	defer c()
 
-	r, err := NewRepositoryClient(context.Background(), "test.example.com/repo1", e)
+	r, err := NewRepository(context.Background(), "test.example.com/repo1", e)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -127,7 +127,7 @@ func TestLayerExists(t *testing.T) {
 	e, c := testServer(m)
 	defer c()
 
-	r, err := NewRepositoryClient(context.Background(), "test.example.com/repo1", e)
+	r, err := NewRepository(context.Background(), "test.example.com/repo1", e)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -227,7 +227,7 @@ func TestLayerUploadChunked(t *testing.T) {
 	e, c := testServer(m)
 	defer c()
 
-	r, err := NewRepositoryClient(context.Background(), repo, e)
+	r, err := NewRepository(context.Background(), repo, e)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -334,7 +334,7 @@ func TestLayerUploadMonolithic(t *testing.T) {
 	e, c := testServer(m)
 	defer c()
 
-	r, err := NewRepositoryClient(context.Background(), repo, e)
+	r, err := NewRepository(context.Background(), repo, e)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -475,7 +475,7 @@ func TestManifestFetch(t *testing.T) {
 	e, c := testServer(m)
 	defer c()
 
-	r, err := NewRepositoryClient(context.Background(), repo, e)
+	r, err := NewRepository(context.Background(), repo, e)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -508,7 +508,7 @@ func TestManifestFetchByTag(t *testing.T) {
 	e, c := testServer(m)
 	defer c()
 
-	r, err := NewRepositoryClient(context.Background(), repo, e)
+	r, err := NewRepository(context.Background(), repo, e)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -553,7 +553,7 @@ func TestManifestDelete(t *testing.T) {
 	e, c := testServer(m)
 	defer c()
 
-	r, err := NewRepositoryClient(context.Background(), repo, e)
+	r, err := NewRepository(context.Background(), repo, e)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -591,7 +591,7 @@ func TestManifestPut(t *testing.T) {
 	e, c := testServer(m)
 	defer c()
 
-	r, err := NewRepositoryClient(context.Background(), repo, e)
+	r, err := NewRepository(context.Background(), repo, e)
 	if err != nil {
 		t.Fatal(err)
 	}
diff --git a/testutil/handler.go b/testutil/handler.go
index fa118cd1..10850e24 100644
--- a/testutil/handler.go
+++ b/testutil/handler.go
@@ -6,6 +6,7 @@ import (
 	"io"
 	"io/ioutil"
 	"net/http"
+	"net/url"
 	"sort"
 	"strings"
 )
@@ -40,16 +41,18 @@ type Request struct {
 func (r Request) String() string {
 	queryString := ""
 	if len(r.QueryParams) > 0 {
-		queryString = "?"
 		keys := make([]string, 0, len(r.QueryParams))
+		queryParts := make([]string, 0, len(r.QueryParams))
 		for k := range r.QueryParams {
 			keys = append(keys, k)
 		}
 		sort.Strings(keys)
 		for _, k := range keys {
-			queryString += strings.Join(r.QueryParams[k], "&") + "&"
+			for _, val := range r.QueryParams[k] {
+				queryParts = append(queryParts, fmt.Sprintf("%s=%s", k, url.QueryEscape(val)))
+			}
 		}
-		queryString = queryString[:len(queryString)-1]
+		queryString = "?" + strings.Join(queryParts, "&")
 	}
 	return fmt.Sprintf("%s %s%s\n%s", r.Method, r.Route, queryString, r.Body)
 }