diff --git a/src/constants/endpoints.js b/src/constants/endpoints.js
index 610b5273..d91b5026 100644
--- a/src/constants/endpoints.js
+++ b/src/constants/endpoints.js
@@ -126,6 +126,10 @@ const endpoints = Object.freeze({
         url: '/clientauth/api/v1/clientauth/validate-client-tag',
         method: 'GET'
     },
+    ValidateClientSignature: {
+        url: '/clientauth/api/v1/clientauth/validate-client-signature',
+        method: 'POST'
+    },
     IsVinbyAddressPermissible: {
         url: '/vehicle/api/v1/vehicle/is-vin-by-address-permissible',
         method: 'Get'
diff --git a/src/helpers/clientauth-helper.js b/src/helpers/clientauth-helper.js
index 2bfd53bb..308ec22b 100644
--- a/src/helpers/clientauth-helper.js
+++ b/src/helpers/clientauth-helper.js
@@ -1,6 +1,6 @@
 import { useMainStore } from '@/store';
 
-const validateISSClientTag = (clientTag) => {
+export function validateISSClientTag(clientTag) {
     const store = useMainStore();
 
     return store.validateClientTag(clientTag)
@@ -8,6 +8,14 @@ const validateISSClientTag = (clientTag) => {
             (response) => response,
             () => null
         );
-};
+}
 
-export default validateISSClientTag;
+export function validateISSClientSignature(clientTag, token, signature) {
+    const store = useMainStore();
+
+    return store.validateClientSignature(clientTag, token, signature)
+        .then(
+            (response) => response,
+            () => null
+        );
+}
diff --git a/src/layouts/entry-page/entry-page.vue b/src/layouts/entry-page/entry-page.vue
index 7a50e3a9..920c60d4 100644
--- a/src/layouts/entry-page/entry-page.vue
+++ b/src/layouts/entry-page/entry-page.vue
@@ -9,7 +9,7 @@
 <script>
 // Supporting files
 import issPageValues from '@/router/router-constants/issPage-values';
-import validateISSClientTag from '@/helpers/clientauth-helper';
+import { validateISSClientTag, validateISSClientSignature } from '@/helpers/clientauth-helper';
 import { useMainStore } from '@/store';
 
 export default {
@@ -44,10 +44,13 @@ export default {
             parseQueryParms() {
                 // Dump the query string parameters into an array. Remove casing on the key for easy compare.
                 const queryStringParams = [];
-                // TODO: Modify to not iterate entire prototype chain
-                for (const param in this.$route.query) {
-                    queryStringParams[param.toLowerCase()] = this.$route.query[param];
+
+                if (this.$route?.query) {
+                    Object.keys(this.$route.query).forEach((param) => {
+                        queryStringParams[param.toLowerCase()] = this.$route.query[param];
+                    });
                 }
+
                 return queryStringParams;
             },
             async validateClientTagOnEntry() {
@@ -60,13 +63,27 @@ export default {
                     const resp = await validateISSClientTag(clientTag);
 
                     if (resp?.data.active && resp?.data.accountName.length > 0) {
-                        this.populateISSConfigValues(resp.data);
+                        if (resp.data.authentication === 'RSAToken') {
+                            const token = queryStringParams.token;
+                            const signature = queryStringParams.signature;
 
-                        authorized = true;
+                            const vsigResp = await validateISSClientSignature(clientTag, token, signature);
+                            this.mainStore.issConfig.isAuthenticated = vsigResp?.data?.valid ?? false;
 
-                        if (resp.data.parameters?.length > 0) {
-                            const finalParams = this.combineClientParameters(resp.data.parameters, queryStringParams);
-                            this.populateStoreItemsFromParams(finalParams);
+                            if (this.mainStore.issConfig.isAuthenticated) {
+                                authorized = true;
+                            }
+                        } else {
+                            authorized = true;
+                        }
+
+                        if (authorized) {
+                            await this.populateISSConfigValues(resp.data);
+
+                            if (resp.data.parameters?.length > 0) {
+                                const finalParams = this.combineClientParameters(resp.data.parameters, queryStringParams);
+                                this.populateStoreItemsFromParams(finalParams);
+                            }
                         }
                     }
                 }
@@ -78,17 +95,13 @@ export default {
                     window.location = `/?issPage=${issPageValues.WELCOME_PAGE}`;
                 }
             },
-            populateISSConfigValues(data) {
+            async populateISSConfigValues(data) {
                 this.mainStore.issConfig.clientName = data.accountName;
                 this.mainStore.issConfig.clientDisplayName = data.accountName; // Defaults to use the client name.
                 this.mainStore.issConfig.accountNumber = data.accountNumber;
                 this.mainStore.issConfig.styleSheet = data.styleSheet;
                 this.mainStore.issConfig.isCoverageEnabled = data.coverageEnabled;
 
-                // NOTE: This is only here for testing purposes.
-                // Will be removed and replaced by actual token / signature validation when work is completed.
-                if (data.authentication === 'RSAToken') this.mainStore.issConfig.isAuthenticated = true;
-
                 try {
                     if (data.clientFlags) {
                         const clientFlags = JSON.parse(data.clientFlags);
@@ -115,19 +128,17 @@ export default {
                 try {
                     const clientParams = JSON.parse(configParams);
 
-                    // TODO: Modify to not iterate entire prototype chain
-                    for (const cparam in clientParams) {
+                    Object.keys(clientParams).forEach((cparam) => {
                         const cname = clientParams[cparam].toLowerCase();
 
-                        // TODO: Modify to not iterate entire prototype chain
-                        for (const qsparam in queryStringParams) {
+                        Object.keys(queryStringParams).forEach((qsparam) => {
                             const qsname = qsparam.toLowerCase();
 
                             if (cname === qsname) {
                                 finalParams[cname] = queryStringParams[cname];
                             }
-                        }
-                    }
+                        });
+                    });
                 } catch (e) {
                     window.console.error(`Error combining client parameters: ${e}`);
                 }
@@ -136,8 +147,8 @@ export default {
             },
             populateStoreItemsFromParams(params) {
                 // Populate store items from parameters.
-                // TODO: Modify to not iterate entire prototype chain
-                for (const param in params) {
+
+                Object.keys(params).forEach((param) => {
                     const name = param.toLowerCase();
                     const value = params[param];
 
@@ -172,7 +183,7 @@ export default {
                             break;
                         default:
                     }
-                }
+                });
             }
         }
 };
diff --git a/src/store/index.js b/src/store/index.js
index 7ca11af4..6252de32 100644
--- a/src/store/index.js
+++ b/src/store/index.js
@@ -344,7 +344,7 @@ export const useMainStore = defineStore({
 
         getDamageOptions(carId) {
             return globalMethods.callHttpClient({
-                methods: endpoints.GetDamageOptions.method,
+                method: endpoints.GetDamageOptions.method,
                 endpoint: `${endpoints.GetDamageOptions.url}/${carId}`,
                 payload: {}
             });
@@ -799,7 +799,7 @@ export const useMainStore = defineStore({
         setVehicle() {
             return globalMethods
                 .callHttpClient({
-                    methods: endpoints.GetVehicle.method,
+                    method: endpoints.GetVehicle.method,
                     endpoint: `${endpoints.GetVehicle.url}/${this.order.vehicle.year}/${this.order.vehicle.make}/${this.order.vehicle.model}/${this.order.vehicle.style}`,
                     payload: {}
                 })
@@ -1535,18 +1535,33 @@ export const useMainStore = defineStore({
 
         async validateZip({ zip }) {
             return await globalMethods.callHttpClient({
-                methods: endpoints.ValidateZip.method,
+                method: endpoints.ValidateZip.method,
                 endpoint: `${endpoints.ValidateZip.url}/${zip}`
             });
         },
 
         async validateClientTag(clientTag) {
             return await globalMethods.callHttpClient({
-                methods: endpoints.ValidateClientTag.method,
+                method: endpoints.ValidateClientTag.method,
                 endpoint: `${endpoints.ValidateClientTag.url}/${clientTag}`
             });
         },
 
+        async validateClientSignature(clientTag, token, signature) {
+
+            const payload = {
+                clientTag,
+                token,
+                signature
+            };
+
+            return await globalMethods.callHttpClient({
+                method: endpoints.ValidateClientSignature.method,
+                endpoint: endpoints.ValidateClientSignature.url,
+                payload
+        });
+        },
+
         saveServiceLocation(serviceLocationInfo) {
             if (this.order.serviceLocation) {
                 if (