diff --git a/lib/call-session.js b/lib/call-session.js
index ee1cd14..1c27b78 100644
--- a/lib/call-session.js
+++ b/lib/call-session.js
@@ -89,7 +89,8 @@ class CallSession extends Emitter {
     this.idleEmitter = this.srf.locals.idleEmitter;
     this.activeCallIds = this.srf.locals.activeCallIds;
     this.writeCdrs = this.srf.locals.writeCdrs;
-
+    this.scheme = 'sip';
+    
     this.decrKey = req.srf.locals.realtimeDbHelpers.decrKey;
 
     const {