## 3 Proposed Methods
### Protocol Description  
**Request for the Route**: Generate the identification of the route for transmitting REQR by Transmitter node (T):  
\(\mathrm{T}\rightarrow\)*:IDT! IDsink! IDREQR! Seq! NT! MAC(KT,IDT! IDsink! IDREQR! Seq! NT) random number is defined by IDREQR, where Seq is the sequence number. The cluster head (node C) receives it, and six cases will be considered:  
**Circumstance 1**: The cluster head will withdraw when receiving REQR, while the parent of the node is not transmitting. **Circumstance 2**: The cluster head will withdraw when receiving REQR, while the parent of the node is transmitting and is a known packet. If the packet has not been received previously, the routing table will be updated with IDsend, IDS, IDsink, and IDREQR. Here, IDsend denotes the ID of the sender node. REQR is then sent as follows:  
\(\mathrm{I}\rightarrow\)*:IDI! IDS! IDsink! IDREQR! Seq! NS! MAC(KS, IDS! IDsink! IDREQR! Seq! NS)  
**Circumstance 3**: When the cluster head generates a REQR initially, and if it is not recognized as a child for the transmitter node, or if it has accepted the REQR before, then it withdraws it. **Circumstance 4**: When the cluster head generates a REQR initially, and if it is represented as a child for the transmitter node, or if it has accepted the REQR before, then their routing table is updated with IDsend, IDS, IDsink, and IDREQR. In addition, it forwards the REQR:  
\(\mathrm{I}\rightarrow\)*:IDI! IDG! IDS! IDsink! IDREQR! Seq! NS! MAC(KS, IDS! IDsink! IDREQR! Seq! NS)  
**Circumstance 5**: When the cluster head receives REQR and has been accepted earlier, then it is withdrawn. **Circumstance 6**: When the cluster head receives REQR, which is not accepted earlier, then the routing table is checked when defining new possible routes. If there is a new route, then REPR is generated for the transmitter node T. If there is no new route, then the routing table is updated with IDsend, IDS, IDsink, and IDREQR. The updated REQR is sent as follows:  
\(\mathrm{G}\rightarrow\)*:IDG! IDS! IDsink! IDREQR! Seq! NS! MAC(KS, IDS! IDsink! IDREQR! Seq! NS)  
Once the receiver node accepts the REQR, the secret key KS fK (IDS0) 0 for the transmitter node has been derived. When a similar route is greater than the Seq of their routing table, then the routing table is updated and the IDS0, IDREQR, Seq, as well as the ID of the earlier cluster head, is collected. Finally, the transmission node transmits REPR. **Reply for the Route**: When REPR is initiated by the receiver node, it transmits:  
Receiver \(\rightarrow\) C: IDE! IDC! IDR! ID receiver! IDREQR! Seq! N! MAC(K<C, receiver>, IDR! ID receiver! IDREQR! Seq! N! IDREQR! Seq! N! MAC(KR, IDR! ID receiver! IDREQR! Seq! N)The earlier node ID is given as IDE, the earlier cluster head ID is given by IDC and K \(<\) C, then the RERP packet is created by the key-sharing of the inter-cluster then,  
C \(\rightarrow\) B: IDE! IDB! IDC! IDC! IDC2! IDR! ID receiver! IDREQR! Seq! N! MAC(KBC, IDR! ID receiver! DREQR! Seq! Ng! IDC2! IDC! IDB)! The earlier node ID is given as IDE, earlier cluster head B ID is given by IDB, transmitting cluster head C ID is given by IDC then the next node's ID is C2 ID. The cluster head of the subsequent hop transmits the authentication output to an earlier node of the cluster head and is given as:  
C2 \(\rightarrow\) C1: C1 ID! C2 ID! IDR! ID receiver! Seq! Werify! MAC(KC1C2, IDR! ID receiver! Seq! IDC1! IDC2! Rverify)  
The verification result is given by Rverify. When C2 has renewed a possible route to the receiver, then Rverify says YES. Else, it will say NO. When the result of the verification is NO, then the subsequent hop of the cluster head does not have a possible route, and REPR is withdrawn by C1. When the result of the verification is YES, then there is a new route for the cluster head. REPR is transmitted by the earlier node. All these operations will be updated in the routing table by the central node. If REPR is accepted by the cluster head, then the initial MAC is authenticated with the subsequent cluster head.