diff --git a/src/session/session_def.h b/src/session/session_def.h
index e17796c..054a484 100644
--- a/src/session/session_def.h
+++ b/src/session/session_def.h
@@ -46,7 +46,7 @@ struct session
 {
     uint64_t id;
     uint64_t stats[MAX_FLOW_DIRECTION][MAX_STAT];
-    uint64_t timestamps[MAX_TIMESTAMP]; // realtime seconds
+    uint64_t timestamps[MAX_TIMESTAMP]; // realtime msec
     struct tcp_half tcp_halfs[MAX_FLOW_DIRECTION];
     struct timeout timeout;
     struct list_head lru;
diff --git a/src/session/session_manager.cpp b/src/session/session_manager.cpp
index b8c41e1..65ca17b 100644
--- a/src/session/session_manager.cpp
+++ b/src/session/session_manager.cpp
@@ -1065,10 +1065,8 @@ void session_manager_free_session(struct session_manager *mgr, struct session *s
      }
 }
 
-struct session *session_manager_lookup_session(struct session_manager *mgr, const struct packet *pkt, uint64_t now_ms)
+struct session *session_manager_lookup_session_by_packet(struct session_manager *mgr, const struct packet *pkt)
 {
-     mgr->now_ms = now_ms;
-
      struct tuple6 key;
      if (packet_get_innermost_tuple6(pkt, &key))
      {
@@ -1085,6 +1083,24 @@ struct session *session_manager_lookup_session(struct session_manager *mgr, cons
      }
 }
 
+struct session *session_manager_lookup_session_by_id(struct session_manager *mgr, uint64_t sess_id)
+{
+     struct session *sess = NULL;
+     sess = session_table_find_sessid(mgr->tcp_sess_table, sess_id, 1);
+     if (sess)
+     {
+          return sess;
+     }
+
+     sess = session_table_find_sessid(mgr->udp_sess_table, sess_id, 1);
+     if (sess)
+     {
+          return sess;
+     }
+
+     return NULL;
+}
+
 int session_manager_update_session(struct session_manager *mgr, struct session *sess, const struct packet *pkt, uint64_t now_ms)
 {
      mgr->now_ms = now_ms;
diff --git a/src/session/session_manager.h b/src/session/session_manager.h
index 46754ab..e665d29 100644
--- a/src/session/session_manager.h
+++ b/src/session/session_manager.h
@@ -97,7 +97,8 @@ void session_manager_record_duplicated_packet(struct session_manager *mgr, const
 struct session *session_manager_new_session(struct session_manager *mgr, const struct packet *pkt, uint64_t now_ms);
 void session_manager_free_session(struct session_manager *mgr, struct session *sess);
 
-struct session *session_manager_lookup_session(struct session_manager *mgr, const struct packet *pkt, uint64_t now_ms);
+struct session *session_manager_lookup_session_by_packet(struct session_manager *mgr, const struct packet *pkt);
+struct session *session_manager_lookup_session_by_id(struct session_manager *mgr, uint64_t sess_id);
 int session_manager_update_session(struct session_manager *mgr, struct session *sess, const struct packet *pkt, uint64_t now_ms);
 
 // return session need free by session_manager_free_session()
diff --git a/src/session/test/gtest_case_tcp_fast_open.cpp b/src/session/test/gtest_case_tcp_fast_open.cpp
index 3cd09a2..139a78d 100644
--- a/src/session/test/gtest_case_tcp_fast_open.cpp
+++ b/src/session/test/gtest_case_tcp_fast_open.cpp
@@ -317,7 +317,7 @@ TEST(CASE, TCP_FAST_OPEN)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
diff --git a/src/session/test/gtest_filter_tcp_dupkt.cpp b/src/session/test/gtest_filter_tcp_dupkt.cpp
index 193e21b..5b3b68e 100644
--- a/src/session/test/gtest_filter_tcp_dupkt.cpp
+++ b/src/session/test/gtest_filter_tcp_dupkt.cpp
@@ -73,7 +73,7 @@ TEST(TCP_DUPKT_FILTER_ENABLE, SYN_DUP)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
@@ -89,7 +89,7 @@ TEST(TCP_DUPKT_FILTER_ENABLE, SYN_DUP)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 2);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 2) == -1);
@@ -108,7 +108,7 @@ TEST(TCP_DUPKT_FILTER_ENABLE, SYN_DUP)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 3);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 3) == 0);
@@ -139,7 +139,7 @@ TEST(TCP_DUPKT_FILTER_ENABLE, SYNACK_DUP)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
@@ -155,7 +155,7 @@ TEST(TCP_DUPKT_FILTER_ENABLE, SYNACK_DUP)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 2);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 2) == -1);
@@ -174,7 +174,7 @@ TEST(TCP_DUPKT_FILTER_ENABLE, SYNACK_DUP)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 3);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 3) == 0);
@@ -206,7 +206,7 @@ TEST(TCP_DUPKT_FILTER_ENABLE, SKIP)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
@@ -224,7 +224,7 @@ TEST(TCP_DUPKT_FILTER_ENABLE, SKIP)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 2);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 2) == 0);
@@ -242,7 +242,7 @@ TEST(TCP_DUPKT_FILTER_ENABLE, SKIP)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 3);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 3) == 0);
@@ -258,7 +258,7 @@ TEST(TCP_DUPKT_FILTER_ENABLE, SKIP)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 3);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 3) == 0);
@@ -292,7 +292,7 @@ TEST(TCP_DUPKT_FILTER_DISABLE, SYN_DUP)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
@@ -308,7 +308,7 @@ TEST(TCP_DUPKT_FILTER_DISABLE, SYN_DUP)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 2);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 2) == 0);
@@ -342,7 +342,7 @@ TEST(TCP_DUPKT_FILTER_DISABLE, SYNACK_DUP)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
@@ -358,7 +358,7 @@ TEST(TCP_DUPKT_FILTER_DISABLE, SYNACK_DUP)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 2);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 2) == 0);
diff --git a/src/session/test/gtest_overload_evict_tcp_sess.cpp b/src/session/test/gtest_overload_evict_tcp_sess.cpp
index 5040390..d5c527f 100644
--- a/src/session/test/gtest_overload_evict_tcp_sess.cpp
+++ b/src/session/test/gtest_overload_evict_tcp_sess.cpp
@@ -136,7 +136,7 @@ TEST(TCP_OVERLOAD, EVICT_NEW_SESS)
     for (uint32_t i = 0; i < RX_BURST_MAX; i++)
     {
         packet_set_ip_src_addr(&pkt, opts.max_tcp_session_num + i);
-        EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+        EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
         EXPECT_TRUE(session_manager_new_session(mgr, &pkt, 1) == NULL);
     }
     printf("=> Session Manager: after evicte new session\n");
diff --git a/src/session/test/gtest_overload_evict_udp_sess.cpp b/src/session/test/gtest_overload_evict_udp_sess.cpp
index c18cc56..fc79e77 100644
--- a/src/session/test/gtest_overload_evict_udp_sess.cpp
+++ b/src/session/test/gtest_overload_evict_udp_sess.cpp
@@ -109,7 +109,7 @@ TEST(UDP_OVERLOAD, EVICT_OLD_SESS)
     for (uint32_t i = 0; i < RX_BURST_MAX; i++)
     {
         packet_set_ip_src_addr(&pkt, i);
-        EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+        EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
         EXPECT_TRUE(session_manager_new_session(mgr, &pkt, 1) == NULL); // hit evicted session, can't renew session
     }
     printf("=> Session Manager: after readd %d evicted sessions\n", RX_BURST_MAX);
@@ -126,7 +126,7 @@ TEST(UDP_OVERLOAD, EVICT_OLD_SESS)
 
     // evicted session timeout
     packet_set_ip_src_addr(&pkt, 0);
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1 + opts.evicted_session_filter_timeout) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     EXPECT_TRUE(session_manager_new_session(mgr, &pkt, 1 + opts.evicted_session_filter_timeout));
     printf("=> Session Manager: after evicted session timeout\n");
     stat = session_manager_stat(mgr);
@@ -188,7 +188,7 @@ TEST(UDP_OVERLOAD, EVICT_NEW_SESS)
     for (uint32_t i = 0; i < RX_BURST_MAX; i++)
     {
         packet_set_ip_src_addr(&pkt, opts.max_udp_session_num + i);
-        EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+        EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
         EXPECT_TRUE(session_manager_new_session(mgr, &pkt, 1) == NULL);
     }
     printf("=> Session Manager: after readd %d evicted session\n", RX_BURST_MAX);
diff --git a/src/session/test/gtest_sess_mgr_tcp_reassembly.cpp b/src/session/test/gtest_sess_mgr_tcp_reassembly.cpp
index 8c2d231..43234ef 100644
--- a/src/session/test/gtest_sess_mgr_tcp_reassembly.cpp
+++ b/src/session/test/gtest_sess_mgr_tcp_reassembly.cpp
@@ -80,7 +80,7 @@ TEST(SESS_MGR_TCP_REASSEMBLY, OUT_OF_ORDER)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
@@ -95,7 +95,7 @@ TEST(SESS_MGR_TCP_REASSEMBLY, OUT_OF_ORDER)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 2);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 2) == 0);
@@ -110,7 +110,7 @@ TEST(SESS_MGR_TCP_REASSEMBLY, OUT_OF_ORDER)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 3);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 3) == 0);
@@ -125,7 +125,7 @@ TEST(SESS_MGR_TCP_REASSEMBLY, OUT_OF_ORDER)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 4);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 4) == 0);
@@ -140,7 +140,7 @@ TEST(SESS_MGR_TCP_REASSEMBLY, OUT_OF_ORDER)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 5);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 5) == 0);
@@ -155,7 +155,7 @@ TEST(SESS_MGR_TCP_REASSEMBLY, OUT_OF_ORDER)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 6);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 6) == 0);
@@ -170,7 +170,7 @@ TEST(SESS_MGR_TCP_REASSEMBLY, OUT_OF_ORDER)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 7);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 7) == 0);
@@ -271,7 +271,7 @@ TEST(SESS_MGR_TCP_REASSEMBLY, SEQ_WRAPAROUND)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
@@ -286,7 +286,7 @@ TEST(SESS_MGR_TCP_REASSEMBLY, SEQ_WRAPAROUND)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 2);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 2) == 0);
@@ -301,7 +301,7 @@ TEST(SESS_MGR_TCP_REASSEMBLY, SEQ_WRAPAROUND)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 3);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 3) == 0);
@@ -320,7 +320,7 @@ TEST(SESS_MGR_TCP_REASSEMBLY, SEQ_WRAPAROUND)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 4);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 4) == 0);
diff --git a/src/session/test/gtest_state_tcp_active_to_closing.cpp b/src/session/test/gtest_state_tcp_active_to_closing.cpp
index bbf78ef..7003b57 100644
--- a/src/session/test/gtest_state_tcp_active_to_closing.cpp
+++ b/src/session/test/gtest_state_tcp_active_to_closing.cpp
@@ -61,7 +61,7 @@ static void build_active_tcp_session(struct session_manager *mgr, struct session
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
@@ -73,7 +73,7 @@ static void build_active_tcp_session(struct session_manager *mgr, struct session
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 2);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 2) == 0);
@@ -105,7 +105,7 @@ TEST(TCP_ACTIVE_TO_CLOSING, BY_FIN_FIN)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 3);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 3) == 0);
@@ -117,7 +117,7 @@ TEST(TCP_ACTIVE_TO_CLOSING, BY_FIN_FIN)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 3);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 3) == 0);
@@ -204,7 +204,7 @@ TEST(TCP_ACTIVE_TO_CLOSING, BY_C2S_RST)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 3);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 3) == 0);
@@ -291,7 +291,7 @@ TEST(TCP_ACTIVE_TO_CLOSING, BY_S2C_RST)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 3);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 3) == 0);
@@ -418,7 +418,7 @@ TEST(TCP_ACTIVE_TO_CLOSING, BY_C2S_HALF_CLOSED_TIMEOUT)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 3);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 3) == 0);
@@ -498,7 +498,7 @@ TEST(TCP_ACTIVE_TO_CLOSING, BY_S2C_HALF_CLOSED_TIMEOUT)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 3);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 3) == 0);
diff --git a/src/session/test/gtest_state_tcp_init_to_opening.cpp b/src/session/test/gtest_state_tcp_init_to_opening.cpp
index 844c0c2..1ea0e14 100644
--- a/src/session/test/gtest_state_tcp_init_to_opening.cpp
+++ b/src/session/test/gtest_state_tcp_init_to_opening.cpp
@@ -73,7 +73,7 @@ TEST(TCP_INIT_TO_OPENING, BY_SYN)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
@@ -151,7 +151,7 @@ TEST(TCP_INIT_TO_OPENING, BY_SYNACK)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
@@ -229,7 +229,7 @@ TEST(TCP_INIT_TO_OPENING, BY_SYN_SYNACK)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
@@ -241,7 +241,7 @@ TEST(TCP_INIT_TO_OPENING, BY_SYN_SYNACK)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 2);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 2) == 0);
@@ -319,7 +319,7 @@ TEST(TCP_INIT_TO_OPENING, BY_SYN_SYNACK_ACK)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
@@ -331,7 +331,7 @@ TEST(TCP_INIT_TO_OPENING, BY_SYN_SYNACK_ACK)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 2);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 2) == 0);
@@ -343,7 +343,7 @@ TEST(TCP_INIT_TO_OPENING, BY_SYN_SYNACK_ACK)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 3);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 3) == 0);
@@ -423,7 +423,7 @@ TEST(TCP_INIT_TO_OPENING, BY_SYN_RETRANSMISSION)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
@@ -440,7 +440,7 @@ TEST(TCP_INIT_TO_OPENING, BY_SYN_RETRANSMISSION)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 2);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 2) == 0);
@@ -520,7 +520,7 @@ TEST(TCP_INIT_TO_OPENING, BY_SYNACK_RETRANSMISSION)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
@@ -538,7 +538,7 @@ TEST(TCP_INIT_TO_OPENING, BY_SYNACK_RETRANSMISSION)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 2);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 2) == 0);
@@ -616,7 +616,7 @@ TEST(TCP_INIT_TO_OPENING, BY_C2S_ASMMETRIC)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
@@ -628,7 +628,7 @@ TEST(TCP_INIT_TO_OPENING, BY_C2S_ASMMETRIC)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 2);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 2) == 0);
@@ -706,7 +706,7 @@ TEST(TCP_INIT_TO_OPENING, BY_S2C_ASMMETRIC)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
@@ -718,7 +718,7 @@ TEST(TCP_INIT_TO_OPENING, BY_S2C_ASMMETRIC)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 2);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 2) == 0);
diff --git a/src/session/test/gtest_state_tcp_init_to_opening_to_active_to_closing_to_closed.cpp b/src/session/test/gtest_state_tcp_init_to_opening_to_active_to_closing_to_closed.cpp
index 4be8039..7eacbff 100644
--- a/src/session/test/gtest_state_tcp_init_to_opening_to_active_to_closing_to_closed.cpp
+++ b/src/session/test/gtest_state_tcp_init_to_opening_to_active_to_closing_to_closed.cpp
@@ -68,7 +68,7 @@ TEST(TCP_INIT_TO_OPENING_TO_ACTIVE_TO_CLOSING_TO_CLOSED, TEST)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
@@ -100,7 +100,7 @@ TEST(TCP_INIT_TO_OPENING_TO_ACTIVE_TO_CLOSING_TO_CLOSED, TEST)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 2);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 2) == 0);
@@ -132,7 +132,7 @@ TEST(TCP_INIT_TO_OPENING_TO_ACTIVE_TO_CLOSING_TO_CLOSED, TEST)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 3);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 3) == 0);
@@ -164,7 +164,7 @@ TEST(TCP_INIT_TO_OPENING_TO_ACTIVE_TO_CLOSING_TO_CLOSED, TEST)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 4);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 4) == 0);
@@ -196,7 +196,7 @@ TEST(TCP_INIT_TO_OPENING_TO_ACTIVE_TO_CLOSING_TO_CLOSED, TEST)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 5);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 5) == 0);
@@ -228,7 +228,7 @@ TEST(TCP_INIT_TO_OPENING_TO_ACTIVE_TO_CLOSING_TO_CLOSED, TEST)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 6);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 6) == 0);
@@ -260,7 +260,7 @@ TEST(TCP_INIT_TO_OPENING_TO_ACTIVE_TO_CLOSING_TO_CLOSED, TEST)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 7);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 7) == 0);
@@ -292,7 +292,7 @@ TEST(TCP_INIT_TO_OPENING_TO_ACTIVE_TO_CLOSING_TO_CLOSED, TEST)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 8);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 8) == 0);
@@ -324,7 +324,7 @@ TEST(TCP_INIT_TO_OPENING_TO_ACTIVE_TO_CLOSING_TO_CLOSED, TEST)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 9);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 9) == 0);
@@ -356,7 +356,7 @@ TEST(TCP_INIT_TO_OPENING_TO_ACTIVE_TO_CLOSING_TO_CLOSED, TEST)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 10);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 10) == 0);
@@ -388,7 +388,7 @@ TEST(TCP_INIT_TO_OPENING_TO_ACTIVE_TO_CLOSING_TO_CLOSED, TEST)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 11);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 11) == 0);
diff --git a/src/session/test/gtest_state_tcp_opening_to_active.cpp b/src/session/test/gtest_state_tcp_opening_to_active.cpp
index ef59682..84974bd 100644
--- a/src/session/test/gtest_state_tcp_opening_to_active.cpp
+++ b/src/session/test/gtest_state_tcp_opening_to_active.cpp
@@ -72,7 +72,7 @@ TEST(TCP_OPENING_TO_ACTIVE, BY_SYN_C2S_DATA)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
@@ -84,7 +84,7 @@ TEST(TCP_OPENING_TO_ACTIVE, BY_SYN_C2S_DATA)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 2);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 2) == 0);
@@ -162,7 +162,7 @@ TEST(TCP_OPENING_TO_ACTIVE, BY_SYNACK_S2C_DATA)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
@@ -174,7 +174,7 @@ TEST(TCP_OPENING_TO_ACTIVE, BY_SYNACK_S2C_DATA)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 2);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 2) == 0);
diff --git a/src/session/test/gtest_state_tcp_opening_to_closing.cpp b/src/session/test/gtest_state_tcp_opening_to_closing.cpp
index f3d4236..aecd130 100644
--- a/src/session/test/gtest_state_tcp_opening_to_closing.cpp
+++ b/src/session/test/gtest_state_tcp_opening_to_closing.cpp
@@ -73,7 +73,7 @@ TEST(TCP_OPENING_TO_CLOSING, BY_FIN_FIN)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
@@ -85,7 +85,7 @@ TEST(TCP_OPENING_TO_CLOSING, BY_FIN_FIN)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 2);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 2) == 0);
@@ -97,7 +97,7 @@ TEST(TCP_OPENING_TO_CLOSING, BY_FIN_FIN)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 3);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 3) == 0);
@@ -174,7 +174,7 @@ TEST(TCP_OPENING_TO_CLOSING, BY_C2S_RST)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
@@ -193,7 +193,7 @@ TEST(TCP_OPENING_TO_CLOSING, BY_C2S_RST)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 2);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 2) == 0);
@@ -270,7 +270,7 @@ TEST(TCP_OPENING_TO_CLOSING, BY_S2C_RST)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
@@ -289,7 +289,7 @@ TEST(TCP_OPENING_TO_CLOSING, BY_S2C_RST)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 2);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 2) == 0);
@@ -365,7 +365,7 @@ TEST(TCP_OPENING_TO_CLOSING, BY_INIT_TIMEOUT)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
@@ -423,7 +423,7 @@ TEST(TCP_OPENING_TO_CLOSING, BY_HANDSHAKE_TIMEOUT)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
@@ -435,7 +435,7 @@ TEST(TCP_OPENING_TO_CLOSING, BY_HANDSHAKE_TIMEOUT)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 2);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 2) == 0);
@@ -513,7 +513,7 @@ TEST(TCP_OPENING_TO_CLOSING, BY_DATA_TIMEOUT)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
@@ -525,7 +525,7 @@ TEST(TCP_OPENING_TO_CLOSING, BY_DATA_TIMEOUT)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 2);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 2) == 0);
@@ -537,7 +537,7 @@ TEST(TCP_OPENING_TO_CLOSING, BY_DATA_TIMEOUT)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 3);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 3) == 0);
@@ -615,7 +615,7 @@ TEST(TCP_OPENING_TO_CLOSING, BY_C2S_HALF_FIN)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
@@ -627,7 +627,7 @@ TEST(TCP_OPENING_TO_CLOSING, BY_C2S_HALF_FIN)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 2);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 2) == 0);
@@ -704,7 +704,7 @@ TEST(TCP_OPENING_TO_CLOSING, BY_S2C_HALF_FIN)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
@@ -716,7 +716,7 @@ TEST(TCP_OPENING_TO_CLOSING, BY_S2C_HALF_FIN)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 2);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 2) == 0);
diff --git a/src/session/test/gtest_state_udp_init_to_opening_to_active_to_closing.cpp b/src/session/test/gtest_state_udp_init_to_opening_to_active_to_closing.cpp
index 2a063d3..d3d563e 100644
--- a/src/session/test/gtest_state_udp_init_to_opening_to_active_to_closing.cpp
+++ b/src/session/test/gtest_state_udp_init_to_opening_to_active_to_closing.cpp
@@ -68,7 +68,7 @@ TEST(UDP_INIT_TO_OPENING_TO_ACTIVE_TO_CLOSING, TEST)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
@@ -99,7 +99,7 @@ TEST(UDP_INIT_TO_OPENING_TO_ACTIVE_TO_CLOSING, TEST)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 2);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 2) == 0);
diff --git a/src/session/test/gtest_state_udp_init_to_opening_to_closing.cpp b/src/session/test/gtest_state_udp_init_to_opening_to_closing.cpp
index e155fbb..d91b91e 100644
--- a/src/session/test/gtest_state_udp_init_to_opening_to_closing.cpp
+++ b/src/session/test/gtest_state_udp_init_to_opening_to_closing.cpp
@@ -73,7 +73,7 @@ TEST(UDP_INIT_TO_OPENING_TO_CLOSING, BY_C2S)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
@@ -152,7 +152,7 @@ TEST(UDP_INIT_TO_OPENING_TO_CLOSING, BY_S2C)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
diff --git a/src/session/test/gtest_timeout_tcp_data.cpp b/src/session/test/gtest_timeout_tcp_data.cpp
index 7d62aac..e7e2700 100644
--- a/src/session/test/gtest_timeout_tcp_data.cpp
+++ b/src/session/test/gtest_timeout_tcp_data.cpp
@@ -64,7 +64,7 @@ TEST(TIMEOUT, TCP_TIMEOUT_DATA)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
@@ -76,7 +76,7 @@ TEST(TIMEOUT, TCP_TIMEOUT_DATA)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 2);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 2) == 0);
diff --git a/src/session/test/gtest_timeout_tcp_handshake.cpp b/src/session/test/gtest_timeout_tcp_handshake.cpp
index b20bdba..8494a93 100644
--- a/src/session/test/gtest_timeout_tcp_handshake.cpp
+++ b/src/session/test/gtest_timeout_tcp_handshake.cpp
@@ -64,7 +64,7 @@ TEST(TIMEOUT, TCP_TIMEOUT_HANDSHAKE)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
diff --git a/src/session/test/gtest_timeout_tcp_init.cpp b/src/session/test/gtest_timeout_tcp_init.cpp
index 5e02667..1debc09 100644
--- a/src/session/test/gtest_timeout_tcp_init.cpp
+++ b/src/session/test/gtest_timeout_tcp_init.cpp
@@ -64,7 +64,7 @@ TEST(TIMEOUT, TCP_TIMEOUT_INIT)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
diff --git a/src/session/test/gtest_timeout_udp_data.cpp b/src/session/test/gtest_timeout_udp_data.cpp
index 5a94a02..29e8c30 100644
--- a/src/session/test/gtest_timeout_udp_data.cpp
+++ b/src/session/test/gtest_timeout_udp_data.cpp
@@ -64,7 +64,7 @@ TEST(TIMEOUT, UDP_TIMEOUT_DATA1)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
@@ -100,7 +100,7 @@ TEST(TIMEOUT, UDP_TIMEOUT_DATA2)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    EXPECT_TRUE(session_manager_lookup_session(mgr, &pkt, 1) == NULL);
+    EXPECT_TRUE(session_manager_lookup_session_by_packet(mgr, &pkt) == NULL);
     // new session
     sess = session_manager_new_session(mgr, &pkt, 1);
     EXPECT_TRUE(sess);
@@ -112,7 +112,7 @@ TEST(TIMEOUT, UDP_TIMEOUT_DATA2)
     printf("<= Packet Parse: done\n\n");
 
     // lookup session
-    sess = session_manager_lookup_session(mgr, &pkt, 2);
+    sess = session_manager_lookup_session_by_packet(mgr, &pkt);
     EXPECT_TRUE(sess);
     // update session
     EXPECT_TRUE(session_manager_update_session(mgr, sess, &pkt, 2) == 0);
diff --git a/src/stellar/stellar_core.cpp b/src/stellar/stellar_core.cpp
index 4ddf37d..83ea43d 100644
--- a/src/stellar/stellar_core.cpp
+++ b/src/stellar/stellar_core.cpp
@@ -213,7 +213,7 @@ static void *work_thread(void *arg)
                 }
             }
 
-            sess = session_manager_lookup_session(sess_mgr, pkt, now_ms);
+            sess = session_manager_lookup_session_by_packet(sess_mgr, pkt);
             if (sess == NULL)
             {
                 sess = session_manager_new_session(sess_mgr, pkt, now_ms);