diff --git a/msg.rkt b/msg.rkt
index 5d73ece..d064eff 100644
--- a/msg.rkt
+++ b/msg.rkt
@@ -12,7 +12,8 @@
 (struct msg [src dst]
   #:transparent)
 
-(struct route [subnet pref self-origin? as-path origin]
+(struct route [nexthop subnet pref self-origin? as-path origin]
+  ;; nexthop : IP
   ;; subnet : Subnet
   ;; pref : Int
   ;; self-origin? : Boolean
@@ -66,7 +67,8 @@
   (match type
     ["update"
      (msg:update src dst
-                 (route (hash->subnet data)
+                 (route src
+                        (hash->subnet data)
                         (hash-ref data 'localpref)
                         (hash-ref data 'selfOrigin)
                         (hash-ref data 'ASPath)
@@ -105,7 +107,8 @@
                 (msg:update
                  (string->ip "1.2.3.4")
                  (string->ip "1.2.3.7")
-                 (route (subnet (string->ip "1.2.3.5") 7)
+                 (route (string->ip "1.2.3.4")
+                        (subnet (string->ip "1.2.3.5") 7)
                         100
                         #t
                         '(1 2)
diff --git a/router b/router
index f49accd..0952a66 100755
--- a/router
+++ b/router
@@ -40,7 +40,18 @@
          If multiple routes have the best origin...
       5. The path from the neighbor router with the lowest IP address.
   |#
-  #t)
+  (let/ec meow
+      (define (cmp mapper)
+        (let ([x2 (mapper r1)]
+              [y2 (mapper r2)])
+            (cond [(< x2 y2) (meow #t)]
+                  [(> x2 y2) (meow #f)])))
+      (cmp (compose - route-pref))
+      (cmp (lambda (x) (if (route-self-origin? x) 1 0)))
+      (cmp (compose length route-as-path))
+      (cmp (lambda (x) (match (route-origin x) ['IGP 3] ['EGP 2] ['UNK 1])))
+      (cmp route-nexthop)
+      (error "your router is angery...")))
 
 ;; Router IP -> (U Peer #f)
 (define (router-find-best rt src-ip)