Subnetting vs Supernetting: The Battle of Address Allocation

Subnetting and supernetting are fundamental techniques in IP networking that help with IP address block allocation and organization. Both have their unique proposals and are made in accordance with different situations.

Subnetting

Subnetting serves as a process of allocating a single network into smaller-sized networks which are otherwise known as subnets. Through such an approach, the second half of the IP address is taken from the network portion and added to the part that belongs to this host, which leads to the emergence of more subnetworks with fewer hosts each. This method has the advantage of slowing down the tackling of IP addresses and giving network administrators the chance to segment the network by class A, B or C.

Here’s a problem scenario related to subnetting:

Problem Scenario:

The company router network holds the ip address range 192.168.1.0/24. The company has four departments: Sales, Human Resources, Information Technology (IT), and Marketing. Each department has its own IP subnet where all IP addresses are networked in one common network at the institution. The IP address requirements of the sales team are 50, the HR team needs 30 IP address, the IT team demands 25 IP addresses, and the marketing team needs 20 IP addresses

Solution:

To tackle this problem, a subnet needs to be created for each department. First, we will establish the subnet size for each department. The subnet size should be in the next highest power of 2, which is the number of required IP addresses.

The Sales department will multiply 50 by the next power of 2 from 2, which is 64. Therefore, we need a subnet size of /64. The subnet mask for a subnet size of 64 in the C Class network is /26 which is derived as 2^(32-26)=64. Consequently, the Sales department will be allowed to use the IP address range of 192.168.1.0/26.

Hence, the technique is required from us for other departments too in the same way. IP range of the human resources (HR) department will be 192.168.1.64/27 (subnet size: (/27) from 192.168.1.96 (net size: 32) will be used for the information technology (IT) department IP and (/27) from 192.168.1.128 (net size: 32) will be used for marketing department IP’s.

Why Subnetting is Important

Enhanced Network Performance

Subnetting is an essential part of network production, which aims to achieve the highest possible efficiency and performance. Division of the large network into smaller subnets can decrease network congestion. This leads to network speed improvement and performance. However, this capability is only possible when the traffic remains localized within the subnets, limiting the number of routers the packets need to pass through and the distance they must travel.

 This logical division of the network into smaller, manageable parts ensures that devices communicate more efficiently, with less competition for bandwidth .

Improved Network Management

Network management becomes more straightforward with subnetting. It allows network administrators to isolate devices into logical groups, simplifying administrative tasks and making it easier to control traffic flow . This organization is particularly beneficial for large firms and companies that need to keep IP addresses geographically localized to maintain efficiency and order . Subnetting also enables administrators to create separate networks for different departments, locations, or device types, which can be managed independently .

Enhanced Network Security

Subnetting vs Supernetting: Subnetting significantly boosts network security. It provides the ability to isolate one network from another, protecting against intrusions and limiting the spread of security breaches. By breaking the network into subnets, administrators can contain compromised networks and prevent further damage. Additionally, subnetting allows for the implementation of security policies that control which hardware and users have access to sensitive data, preventing users from accessing areas of the network where they don’t belong.

Efficient Use of IP Addresses

Subnetting allows for the efficient allocation of IP addresses. It overcomes limitations in local area networks, such as the maximum number of allowed hosts, by enabling more devices to be added to a network without the need for additional IP addresses or network infrastructure . This efficient use of IP addresses is especially important given the limited availability of IPv4 addresses.

Simplified Maintenance and Remote Access

Maintenance is easier with subnetting, especially in the case of small networks . It also facilitates remote access, allowing people to connect to a work network from their homes without exposing the entire network to potential security risks .

Read Also: Exploring the Wireless World: Unraveling the Wonders of Wireless Networking

Supernetting

Supernetting as well is a technique that is used to integrate several smaller networks to form the bigger one, which is commonly termed as route aggregation, route summarization. It is carried out for the purpose of smaller routing tables, optimization of routing performance, and preservation of the IP address space.

In contrast to that, Supertagging which is an activity of putting together several smaller networks in a common and bigger one, which is also called route aggregation or route summarization. The last step is to decrease the size of routing tables and optimize the performance of routing as well as save IP address space.

Supernetting measures the length of host bits, which is exactly the opposite of netting that increases the length of the prefix bits. One can reach CIDR via a switching device’s operation known as supernetting.

When speaking of networking, supernetting, or in other names route aggregation or route summarization, is any of the methods in which it becomes possible to join a lot of smaller networks onto one big network. For this main task, the problems like the overload on routing, the reduction of routing table sizes and allocation of less IP address space are prioritized matters to prevent confusion and interruption in information passage.

Consider an example where we have four Class C networks: 192.0.2.0/24, 192.0.3.0/24, 192.0.4.0/24, and 192.0.5.0/24.Every one of these networks has its own subnet mask which is of 255.255.255.0. To do so, one should interpret accordingly the first three octets (192.0.2, 192.0.3, 192.0.4, and 192.0.5) as consisting of the network addresses, and the last one (.0 to .255) as being the host addresses within each network.

In order to combine these four networks into a larger network, we do have to change what we use as a subnet mask, here. Such as by altering the subnet mask to 255.255.252.0 means that we are “tunneling” two bits out from the network side of the address. Which now covers the 192.0.2.0 and the end of the 192.0.5.255.Number. The supernet (192.0.2.0/22) span can consist of 1022 individual host addresses, but the first and the last addresses are reserved as a supernet address (network address) and the broadcast address respectively.

Supernetting, also known as Classless Inter-Domain Routing (CIDR), offers several key advantages:The supernetting, usually referred to as the classless inter-domain routing (CIDR), may cover up the following crucial advantages:

Efficient Use of IP Addresses: IP addressing is dealt with Supernetting during which IP range can be split into subnets with fewer IP addresses being needed for a network. It does so by creating a single large network resulting out of the combination of several networks that are otherwise idled. Thus, the number of IP addresses becomes almost wasted.

1. Simplified Routing: Supernetting creates a new route which is mapped across a large number of address ranges, thereby reducing the number of entries in the routing table. Instead of having a unique route set, including all network details, a router may only have a solitary routing entry for the whole range of numbers.
2. Reduced Network Traffic: Supernetting also helps in reducing the amount of network traffic caused by routing updates. This is achieved by minimizing the number of routing table entries.
3. Increased Network Performance: With fewer routing table entries and less network traffic, the overall performance of the network can be improved.
4. Scalability: Supernetting allows for greater network scalability. As a network grows, it can be divided into smaller subnets. However, these subnets can still be grouped together into a larger supernet for routing purposes.