# Enhancing Data Security Through VLSM Subnetting and TCP/IP Model in an ENT
## 5 Discussion  
ENT is a hierarchical or tree network topology and other topologies such as mesh and star or both can serve as a hybrid topology to deliver a similar network design based on VLSM subnetting. Infrastructure network can be reliable and secure to support business operations when adequately configured. The infrastructure network design is performed based on VLSM strategy, packet sending protocols, security protocols, topology, internet protocol addressing schemes, and vital network components configurations to build a resourceful local network for information and data transmission and security. Devices communicate through protocols and technologies such TCP/IP, Wi-Fi, and Ethernet. The protocols create guidelines relating to the transmission of data, routing, error detection, and IP addressing--unique identifiers enabling communication amongst hosts across the network. The address is 32-bit-based represented by four (4) octets which represented host or network bits of the specified IP address (192.168.5.0). In networking, TCP/IP links information systems organised in a network, and can encrypt data prior to movement through public or private network relating to the VPN. The smart farming, home, and healthcare devices utilise TCP/IP to transmit data with reference to the Internet of Things. Additionally, Voice Over Internet Protocol (VIOP) can use TCP/IP for communication--calls over the Internet such as Skype, WhatsApp, TeamViewer, and Google Voice. The Updates TCP/IP model is further demonstrated with the scenario below about End-Users. 1. An End-User1 decides to send an email to End-User2. End-User1 opens the email client and composes a message. 2. End-User1's device utilises a Transport Layer of TCP/IP model to send the message. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Protocol** & **EIGRP** & **OSPF** & **RIP** \\ \hline Type of network topology & Hybrid & Link-state & Distance vector \\ \hline Knowledge of network topology & Maintains limited topology table & Maintains table with complete knowledge of each area & None \\ \hline \multirow{3}{*}{Routing updates} & Incremental updates sent to affected routers when necessary & Incremental updates sent to all routers in an area when necessary & Complete routing table sent to all neighbours every 30 s \\ \hline \multirow{3}{*}{
\begin{tabular}{c} Acknowledgments after receiving routing updates \\ \end{tabular} } & \multirow{3}{*}{ACK packet sent} & \multirow{3}{*}{LSAck packet sent} & \multirow{3}{*}{None} \\ \hline Convergence & Fast & Fast & Slow \\ \hline Prone to routing loops & No & No & Yes \\ \hline Supports VLSMs & Yes & Yes & No \\ \hline Supports route summarisation on arbitrary boundaries & Yes & Yes & No \\ \hline Supports hierarchical routing & Yes & Yes & No \\ \hline Supports multiple protocols & Yes & No & No \\ \hline Suitability for large network & Yes & Yes & No \\ \hline Bandwidth consumption & Low & Moderate & High \\ \hline Enhance data security & Yes (HMAC-SHA-256) & Yes (SHA) & Yes (MD5) \\ \hline \hline \end{tabular}
\end{table} 
Table 7: Performance and security of various routing protocols. * The router assesses the destination IP address of the message and checks where the message should be sent to the device on another network used by End-User2. * The router sends the message to the next router in the path to a device using End-User3. The message continues until the message arrives at End-User2's device. * When the message gets to End-User2's device, the Application Layer of the TCP/IP model shows the message in the email client of End-User2
* If packets about the massage were damaged or lost in the transmission process, the TCP/IP model's Transport Layer can detect errors and request which sender retransmitted the damaged or lost packets. While a fixed subnet mask results in an inefficient use of IP addresses where several subnets have diverse requirements for multiple devices, the VLSM offers subnet masks of variable lengths within a network using a single IP address.