diff --git a/lib/src/aasStore.ts b/lib/src/aasStore.ts
index 9952a10..7b9c0fa 100644
--- a/lib/src/aasStore.ts
+++ b/lib/src/aasStore.ts
@@ -4,7 +4,7 @@ import { types, jsonization } from "@aas-core-works/aas-core3.0rc02-typescript";
 
 export default class AASStore {
     private static instance: AASStore;
-    private shells: Array<types.Environment> = [];
+    private envs: Array<types.Environment> = [];
 
     private constructor() { }
 
@@ -17,17 +17,17 @@ export default class AASStore {
     }
 
     public addAAS(aas: types.Environment): void {
-        this.shells.push(aas);
+        this.envs.push(aas);
     }
 
     public getAll(): Array<types.Environment> {
-        return this.shells;
+        return this.envs;
     }
 
     public addAASByPath(path: string): void {
         if (!path.endsWith(".json")) throw new Error("File must be a JSON file");
 
-        const file = getAASFileContent(path);
+        const file = readFileSync(path, { encoding: "utf-8" });
 
         const aas = JSON.parse(file);
         const aasJson = jsonization.environmentFromJsonable(aas);
@@ -39,7 +39,7 @@ export default class AASStore {
     public addAllAASFromPath(path: string): void {
         const errors: any[] = [];
 
-        getAllAASFiles(path).forEach(file => {
+        this.getAllAASFilePaths(path).forEach(file => {
             try {
                 this.addAASByPath(file);
             } catch (e) {
@@ -50,24 +50,43 @@ export default class AASStore {
         throw errors;
     }
 
-}
-
-export function getAllAASFiles(aasPath: string): string[] {
-    const files = readdirSync(aasPath);
-    return files.filter(file => file.endsWith(".json")).map(file => `${aasPath}/${file}`);
-}
-
-export function getAASFileContent(aasPath: string): string {
-    const content = readFileSync(aasPath, { encoding: "utf-8" });
-    return content;
-}
-
-export function getAllAASFileContents(aasPath: string): string[] {
-    const files = getAllAASFiles(aasPath)
-    const content = [];
-    for (const file of files) {
-        content.push(getAASFileContent(file));
+    private getAllAASFilePaths(aasPath: string): string[] {
+        const files = readdirSync(aasPath);
+        return files.filter(file => file.endsWith(".json")).map(file => `${aasPath}/${file}`);
     }
 
-    return content;
+    public findAASById(id: string): types.AssetAdministrationShell | null {
+        for (const env of this.envs) {
+            if (env.assetAdministrationShells === null) continue;
+
+            for (const aas of env.assetAdministrationShells) {
+                if (aas.id === id) return aas;
+            }
+        }
+
+        return null;
+    }
+
+    public findSMById(id: string): types.Submodel | null {
+        for (const env of this.envs) {
+            if (env.submodels === null) continue;
+
+            for (const sm of env.submodels) {
+                if (sm.id === id) return sm;
+            }
+        }
+
+        return null;
+    }
+
+    public findElement(submodelId: string, elementIdShort: string): types.Class | null {
+        const sm = this.findSMById(submodelId);
+        if (!sm) return null;
+
+        for (const element of sm.descend()) {
+            if ((element as any).idShort === elementIdShort) return element;
+        }
+
+        return null;
+    }
 }
\ No newline at end of file
diff --git a/lib/src/interfaceConnectionObject.ts b/lib/src/interfaceConnectionObject.ts
index caee23b..d8aa99c 100644
--- a/lib/src/interfaceConnectionObject.ts
+++ b/lib/src/interfaceConnectionObject.ts
@@ -6,13 +6,14 @@ export type OnResponseCallback = (response: any) => void
 
 export default abstract class InterfaceConnectionObject<ConfigInterface> {
     protected abstract readonly name: string;
+    protected abstract readonly uriProtocol: string[]|string;
     protected abstract readonly connectionType: ConnectionType;
     protected abstract readonly supportsSubscriptions: boolean;
 
     protected config: ConfigInterface;
     private onResponseCallback: OnResponseCallback;
 
-    constructor(config: ConfigInterface, onResponseCallback: OnResponseCallback) {
+    public constructor(config: ConfigInterface, onResponseCallback: OnResponseCallback) {
         this.config = config;
         this.onResponseCallback = onResponseCallback;
     }
diff --git a/lib/src/multimessageBroker.ts b/lib/src/multimessageBroker.ts
index d9ed2e0..c6eaed9 100644
--- a/lib/src/multimessageBroker.ts
+++ b/lib/src/multimessageBroker.ts
@@ -1,6 +1,6 @@
 import { types } from "@aas-core-works/aas-core3.0rc02-typescript";
 import type AASInterfaceServer from "server";
-import type { PossibleRequests } from "server";
+import type { Request } from "types/requests";
 import type InterfaceConnectionObject from "interfaceConnectionObject";
 import AASStore from "aasStore";
 
@@ -9,11 +9,11 @@ class MultiMessageBroker {
 
     private serverInterfaces: Array<typeof AASInterfaceServer> = [];
     private serverInterfaceConfigs: Array<any> = [];
-    private serverInstances: Array<AASInterfaceServer<any>|null> = [];
+    private serverInstances: Array<AASInterfaceServer<typeof this.serverInterfaceConfigs[keyof typeof this.serverInterfaceConfigs]>|null> = [];
 
     private connectorInterfaces: Array<typeof InterfaceConnectionObject> = [];
     private connectorConfigs: Array<any> = [];
-    private connectorInstances: Array<InterfaceConnectionObject<any>|null> = [];
+    private connectorInstances: Array<InterfaceConnectionObject<typeof this.connectorConfigs[keyof typeof this.connectorConfigs]>|null> = [];
 
     public constructor() {}
 
@@ -51,7 +51,11 @@ class MultiMessageBroker {
         });
     }
 
-    private onInterfaceRequest(request: PossibleRequests) {
+    private connectorConfigsFromAAS(aas: types.Environment): void {
+        // TODO
+    }
+
+    private onInterfaceRequest(request: Request) {
         // TODO
     }
 
diff --git a/lib/src/server.ts b/lib/src/server.ts
index b4e68e9..e0d223a 100644
--- a/lib/src/server.ts
+++ b/lib/src/server.ts
@@ -1,16 +1,16 @@
 import { types } from "@aas-core-works/aas-core3.0rc02-typescript";
-
-export type PossibleRequests = "TODO";
-
-export type OnRequestCallback = (request: PossibleRequests) => void
+import type { Request, OnRequestCallback } from "types/requests";
 
 export default abstract class AASInterfaceServer<ConfigInterface> {
     protected abstract readonly name: string;
     protected config: ConfigInterface;
-    private onRequestCallback: OnRequestCallback;
+    protected abstract readonly supportsSubscriptions: boolean;
+    protected readonly aas: types.Environment;
+    private onRequestCallback: OnRequestCallback
     
     constructor(config: ConfigInterface, aas: types.Environment, onRequestCallback: OnRequestCallback) {
         this.config = config;
+        this.aas = aas;
         this.onRequestCallback = onRequestCallback;
     }
 
@@ -19,5 +19,24 @@ export default abstract class AASInterfaceServer<ConfigInterface> {
     public abstract stop(): void;
     public abstract notify(event: any): void;
 
-    protected abstract findElementByRequest(request: PossibleRequests): any | null;
+    protected abstract findElementByRequest(request: Request): any | null;
+
+    protected findElementBySemanticId(id: string): types.Class | null {
+        for (const element of this.aas.descend()) {
+            if ((element as any).semanticId === id) {
+                return element;
+            }
+        }
+        return null;
+    }
+
+    protected findElementByShortId(id: string): types.Class | null {
+        for (const element of this.aas.descend()) {
+            if ((element as any).idShort === id) {
+                return element;
+            }
+        }
+        return null;
+    }
+
 }
\ No newline at end of file
diff --git a/lib/src/types/requests.ts b/lib/src/types/requests.ts
new file mode 100644
index 0000000..053f1f3
--- /dev/null
+++ b/lib/src/types/requests.ts
@@ -0,0 +1,3 @@
+export type Request = "TODO"
+
+export type OnRequestCallback = (request: Request) => void
\ No newline at end of file