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Autonomous System Numbers (ASNs): The Complete Guide to Understanding and Acquiring One

In this comprehensive guide, we’ll dive into the world of Autonomous System Numbers (ASNs), explaining what they are, why you might need one, and how to acquire them. Our goal is to provide you with a thorough understanding of ASNs to help you make informed decisions for your networking needs

Defining Autonomous System Numbers (ASNs)

An Autonomous System Number (ASN) is a unique identifier assigned to an Autonomous System (AS) on the Internet. An AS is a group of IP addresses and their associated routes under the control of a single organization, such as an Internet Service Provider (ISP) or a large enterprise.

ASNs are crucial in ensuring the proper functioning of the Border Gateway Protocol (BGP), which is responsible for routing traffic between ASes on the Internet. By using ASNs, BGP can efficiently route traffic to its intended destination, allowing for a more stable and reliable Internet experience.

The Role of ASNs in Internet Routing

ASNs play a vital role in the global Internet routing infrastructure. They serve as unique identifiers for ASes and allow BGP to make informed decisions about how to route traffic. Here are the key functions of ASNs in Internet routing:

  1. Path Selection: BGP uses ASNs to build a list of ASes that a particular route traverses. This information is used to select the best path for data packets to reach their destination.
  2. Loop Prevention: By examining the list of traversed ASes, BGP can detect and prevent routing loops, ensuring that traffic is routed efficiently and without unnecessary delays.
  3. Policy Enforcement: ASNs enable network administrators to implement routing policies based on specific ASes, allowing for fine-grained control over traffic flow.

Public and Private ASNs

There are two types of ASNs: public and private.

Public ASNs are globally unique identifiers assigned by the Internet Assigned Numbers Authority (IANA) or its Regional Internet Registries (RIRs) such as ARIN, RIPE NCC, APNIC, LACNIC, and AFRINIC. Public ASNs are used by organizations that require a unique ASN to establish external BGP connections with other ASes on the Internet.

Private ASNs, on the other hand, are reserved for internal use within an organization and are not intended for use on the public Internet. These ASNs are not globally unique and fall within the range of 64512 to 65534, as specified by RFC 6996. Private ASNs are commonly used in private networks or for internal BGP connections between routers within a single AS.

Do You Need an ASN?

Determining whether your organization needs an ASN depends on your networking requirements. You may need an ASN if:

  1. You are an Internet Service Provider (ISP): ISPs require ASNs to establish BGP connections with other ISPs and exchange routing information.
  2. You operate a multi-homed network: If your organization has connections to multiple ISPs for redundancy or load balancing, you will need an ASN to manage your BGP connections and routing policies.
  3. You have a large enterprise network: Large organizations with complex network topologies may benefit from using BGP and an ASN to manage their internal routing.

If you only have a single connection to an ISP and do not require complex routing policies, you most likely do not need an ASN.

How to Obtain an ASN

If you determine that your organization requires an ASN, follow these steps to obtain one:

  1. Identify your Regional Internet Registry (RIR): Determine the RIR responsible for managing IP addresses and ASNs in your region. The five RIRs are:
    • ARIN (North America)
    • RIPE NCC (Europe, Middle East, and Central Asia)
    • APNIC (Asia Pacific)
    • LACNIC (Latin America and the Caribbean)
    • AFRINIC (Africa)
  2. Create an account with your RIR: Register an account on your RIR’s website to start the ASN application process.
  3. Submit an ASN application: Fill out the ASN application form, providing details about your organization and its networking requirements. Ensure you have a clear justification for requesting an ASN, as RIRs evaluate applications based on demonstrated need.
  4. Pay the application fee: There is typically a one-time application fee for obtaining an ASN, as well as an annual maintenance fee. These fees vary by RIR.
  5. Wait for approval: The RIR will review your application and may request additional information. Once your application is approved, you will be assigned a unique ASN.

Managing Your ASN

Once you have obtained an ASN, follow these guidelines to manage it effectively:

  1. Configure BGP on your routers: Set up BGP on your network routers and establish BGP sessions with your ISP(s) or other ASes using your assigned ASN.
  2. Implement routing policies: Develop and apply routing policies that control how traffic is routed between your AS and other ASes on the Internet. Consider aspects such as traffic engineering, load balancing, and redundancy.
  3. Monitor your BGP sessions: Regularly monitor your BGP sessions to ensure they are stable and performing as expected. Be prepared to troubleshoot any issues that may arise.
  4. Keep your RIR account information up to date: Ensure your organization’s contact information is current with your RIR, as this is important for maintaining your ASN registration and receiving important notifications.
  5. Participate in relevant mailing lists and forums: Stay informed about BGP and ASN-related topics by subscribing to mailing lists and participating in forums within your RIR community.

ASN Best Practices

To ensure the smooth operation of your AS and promote a healthy Internet routing ecosystem, follow these ASN best practices:

  1. Filtering: Implement strict ingress and egress filtering policies to prevent the propagation of incorrect or malicious routing information.
  2. Prefix aggregation: Where possible, aggregate your IP address prefixes to minimize the size of global routing tables and improve overall routing efficiency
  3. Maintain accurate routing information: Keep your Internet Routing Registry (IRR) records up to date to facilitate proper route filtering and validation by other ASes.
  1. Implement Resource Public Key Infrastructure (RPKI): Utilize RPKI to cryptographically validate the authenticity of your routing announcements, reducing the risk of route hijacking and misconfiguration.
  2. Monitor for routing anomalies: Regularly monitor your routing announcements and incoming traffic for anomalies that may indicate misconfiguration or malicious activity.
  3. Collaborate with the networking community: Engage with the larger networking community, participating in events and sharing experiences and knowledge to help improve the overall stability and security of the Internet routing system.

ASN and BGP Routing Overview

To help visualize the role of ASNs in the BGP routing process, consider the following diagram:

In this example, AS 100, AS 200, AS 300, and AS 400 are Autonomous Systems with their respective ASNs. AS 100 has BGP peering sessions established with AS 200 and AS 400, while AS 200 and AS 300 have their own BGP peering sessions. The diagram illustrates how ASNs facilitate the exchange of routing information and the proper routing of traffic between ASes.

By understanding the importance of ASNs and following the best practices outlined in this guide, your organization can effectively manage its ASN and contribute to a stable and secure global routing infrastructure. Whether you’re an ISP, a multi-homed network, or a large enterprise, acquiring and properly managing an ASN is a key component in ensuring the smooth operation of your network and providing a reliable Internet experience for your users.

Additional ASN Resources

To further expand your knowledge and understanding of ASNs, BGP, and Internet routing, consider exploring the following resources:

  1. RFC 4271 – Border Gateway Protocol 4 (BGP-4): This document serves as the primary specification for the BGP protocol, detailing its features and operations. Read the RFC 4271 here.
  2. RFC 6793 – Increasing the Number of ASNs: This RFC discusses the extension of the ASN space to support a larger number of ASNs, ensuring the continued growth of the Internet. Read the RFC 6793 here.
  3. PeeringDB: PeeringDB is a comprehensive database of networks, facilities, and interconnection services. It allows organizations to find potential peering partners and exchange information. Visit PeeringDB.
  4. BGP Route Monitoring Tools: There are various tools available for monitoring BGP routes, such as BGPStream and RIPEstat. These tools can help you analyze routing information and detect anomalies in real-time.
  5. Internet Routing Registries (IRRs):IRRs are databases that store routing information, such as ASNs, IP prefixes, and routing policies. They are used by network operators to configure and maintain routing policies. Some popular IRRs include RADb, RIPE NCC’s IRR, and ARIN’s IRR.
  1. BGP Training and Certification Programs: To gain a deeper understanding of BGP and ASN management, consider enrolling in a training course or certification program. Many organizations offer specialized training in BGP and Internet routing, such as Cisco, Juniper Networks, and NANOG.

By delving into these resources and actively engaging with the networking community, you can build a strong foundation in ASN management, BGP routing, and Internet infrastructure. This knowledge will not only benefit your organization but also contribute to a more stable, secure, and efficient global Internet.

Future Trends in ASNs and Internet Routing

As the Internet continues to evolve, the role of ASNs and the importance of effective routing strategies will only grow more critical. Here are some future trends to watch for in the world of ASNs and Internet routing:

  1. Increased Adoption of RPKI: With the increasing focus on Internet routing security, the adoption of RPKI for route origin validation is expected to grow. Network operators and the broader community should prioritize the implementation of RPKI to enhance the overall security and stability of the Internet routing system.
  2. IPv6 Transition: As the IPv4 address space becomes more scarce, the transition to IPv6 is inevitable. This shift will impact the way BGP operates and handles routing information, requiring network operators to become familiar with IPv6-specific routing concepts and best practices.
  3. Automation and Machine Learning: With advancements in automation and machine learning, network operators may increasingly rely on intelligent systems to manage their ASNs and optimize routing policies. These technologies could help improve routing efficiency, detect anomalies, and predict potential issues in the Internet routing infrastructure.
  4. Collaborative Security Initiatives: As cyber threats become more sophisticated, collaborativesecurity initiatives will be crucial in combating them. Networking communities, such as MANRS (Mutually Agreed Norms for Routing Security), aim to improve the security and resilience of the global routing system. Participating in such initiatives and adopting their recommendations will help organizations contribute to a more secure Internet.
  1. Inter-domain Traffic Engineering: With the growing complexity of the Internet, inter-domain traffic engineering techniques will play an increasingly important role in optimizing traffic flow between ASes. Implementing advanced traffic engineering strategies, such as Segment Routing (SR) and Software-Defined Networking (SDN), can help network operators achieve greater control over their traffic and improve the overall performance of their networks.

By staying informed about these future trends and embracing new technologies and practices, organizations can ensure that their ASN management and routing strategies remain effective and contribute to a stable and secure global Internet infrastructure.


In conclusion, ASNs are critical components of the global Internet routing infrastructure, serving as unique identifiers for Autonomous Systems and facilitating efficient routing of traffic. By understanding the importance of ASNs and following best practices for managing them, organizations can optimize their networks and contribute to a more reliable and secure Internet.

To stay ahead in the ever-evolving world of Internet routing, organizations should continue to invest in their knowledge and skills related to ASN management, BGP routing, and associated technologies. By embracing future trends, adopting new security practices, and participating in collaborative initiatives, network operators can ensure their routing strategies remain effective and adapt to the changing needs of the global Internet.

The key to success in ASN management and Internet routing lies in continuous learning, collaboration, and innovation. By investing in these areas and maintaining a strong foundation in best practices, your organization will be well-positioned to thrive in the complex world of ASNs and global Internet routing.


The Comprehensive Guide to IPv4 Brokers: The Key Players in the IPv4 Market

Introduction to IPv4 Brokers

IPv4 brokers are specialized intermediaries who facilitate the transfer of IPv4 address space between buyers and sellers. As the demand for IPv4 addresses continues to grow, and the supply remains limited, these professionals play a crucial role in ensuring that organizations can access the IP resources they need to maintain and expand their online presence.

The Significance of IPv4 Brokers in Today’s Internet Landscape

In the early days of the internet, the IPv4 address space was considered vast enough to accommodate the growing number of connected devices. However, as the internet expanded exponentially, the limitations of IPv4’s 32-bit address space became apparent, leading to the exhaustion of available IPv4 addresses.

IPv4 brokers have become increasingly important in today’s internet landscape for several reasons:

  1. IPv4 address scarcity: With the depletion of IPv4 addresses, organizations looking to obtain additional address space must rely on IPv4 brokers to facilitate transactions in the secondary market.
  2. IPv4 address value: As demand outstrips supply, the value of IPv4 addresses has grown, making them a valuable asset for companies that own large, unused address blocks.
  3. IPv6 transition: While the internet community has been working towards adopting the IPv6 addressing standard, the transition has been slow. As a result, IPv4 brokers remain essential for businesses that need IPv4 addresses to maintain their online operations.

How IPv4 Brokers Facilitate IPv4 Address Transactions

IPv4 brokers play a vital role in the IPv4 address market by providing the following services:

  1. Market assessment: They help both buyers and sellers understand the current market conditions and the value of the IPv4 addresses being traded.
  2. Matching buyers and sellers: IPv4 brokers connect organizations looking to buy IPv4 addresses with those that have surplus address space to sell.
  3. Negotiation support: They assist with price negotiations, helping both parties reach a mutually beneficial agreement.
  4. Legal and regulatory compliance: IPv4 brokers ensure that all transactions adhere to the policies and regulations set forth by the relevant Regional Internet Registries (RIRs) and any applicable local laws.
  5. Transfer facilitation: They handle the logistics of transferring IPv4 address blocks between the buyer’s and seller’s RIR accounts, ensuring a smooth and efficient process.
  6. Post-transfer support: IPv4 brokers provide ongoing assistance to both parties, addressing any concerns or issues that may arise after the completion of the transaction.

Advantages of Working with an IPv4 Broker

Partnering with an IPv4 broker offers several benefits for organizations in need of IPv4 addresses:

  1. Efficiency: IPv4 brokers can quickly connect buyers and sellers, streamlining the process and saving time for both parties.
  2. Expertise: Experienced IPv4 brokers possess in-depth knowledge of the IPv4 market, regulatory requirements, and RIR policies, ensuring that transactions are completed accurately and in compliance with all relevant guidelines.
  3. Risk mitigation: By handling the legal and technical aspects of the transaction, IPv4 brokers help minimize the risk of complications or disputes.
  4. Negotiation support: IPv4 brokers serve as neutral third parties, helping to facilitate negotiations and arrive at a fair price for the IPv4 addresses being traded.
  5. Trust and credibility: Reputable IPv4 brokers have established relationships with RIRs and other industry stakeholders, lending credibility to the transaction and increasing trust between the buyer and seller

Selecting the Right IPv4 Broker for Your Needs

When choosing an IPv4 broker to work with, consider the following factors to ensure you select a reliable and reputable partner:

  1. Experience: Opt for a broker with a proven track record of successful IPv4 address transactions, as they will be better equipped to handle the complexities of the process.
  2. Industry reputation: Check for client testimonials, case studies, and industry references to gauge the broker’s reputation and the quality of their services.
  3. Accreditation: Some RIRs maintain a list of accredited IPv4 brokers. Working with an accredited broker can provide an additional level of trust and confidence in the transaction.
  4. Transparency: A good broker should be transparent about their fees, processes, and the steps involved in the IPv4 address transfer.
  5. Customer support: A responsive and helpful customer support team is essential, as it ensures that any questions or concerns are addressed promptly and efficiently.

Preparing for the Future: IPv6 Adoption

While IPv4 brokers play a critical role in the current internet landscape, the long-term solution to the limitations of IPv4 lies in the widespread adoption of IPv6. The IPv6 addressing standard offers a vastly larger address space, ensuring that the internet can continue to grow and accommodate the ever-increasing number of connected devices.

Organizations should consider the following steps to prepare for the inevitable transition to IPv6:

  1. IPv6 readiness assessment: Conduct an assessment of your current infrastructure, applications, and services to determine their compatibility with IPv6 and identify any necessary upgrades or changes.
  2. Dual-stack implementation: Implement a dual-stack approach, where both IPv4 and IPv6 are supported simultaneously, to ensure a smooth transition without disrupting your online operations.
  3. Staff training: Ensure that your IT staff is well-versed in IPv6 concepts, configuration, and management to effectively handle the migration and ongoing maintenance.
  4. IPv6 monitoring and security: Update your network monitoring and security tools to be IPv6-compliant, as new addressing standards may require adjustments to your existing monitoring and security practices.
  5. Collaboration with partners and vendors: Work closely with your internet service providers, hosting providers, and other partners to ensure a coordinated and efficient transition to IPv6.

In conclusion, IPv4 brokers play a crucial role in today’s internet landscape, as they facilitate the acquisition and transfer of IPv4 addresses in the face of growing scarcity. By partnering with a reputable and experienced IPv4 broker, organizations can more easily navigate the IPv4 market and secure the address resources they need. However, it’s also vital for businesses to prepare for the eventual shift to IPv6, as this addressing standard represents the long-term solution to the

Leveraging the InterLIR Marketplace for IPv4 Transactions

In addition to working with IPv4 brokers, organizations can also take advantage of the InterLIR marketplace for IPv4 address transactions. The InterLIR marketplace is an online platform that brings together buyers and sellers of IPv4 address space, providing a transparent and efficient environment for trading IPv4 resources.

Here are the key benefits of using the InterLIR marketplace:

  1. Accessibility: The marketplace is available to all organizations with an account at their respective RIR, making it easy for a wide range of participants to engage in IPv4 address transactions.
  2. Transparency: The InterLIR marketplace provides a clear view of the available IPv4 address blocks, along with their prices, allowing buyers and sellers to make informed decisions based on current market conditions.
  3. Streamlined process: The marketplace automates many aspects of the IPv4 transfer process, such as ensuring compliance with RIR policies, simplifying the transaction for both buyers and sellers.
  4. Cost-effectiveness: By eliminating the need for a middleman, the InterLIR marketplace can potentially reduce transaction costs for participants.
  5. Flexibility: The marketplace allows for various transaction types, including leasing, purchasing, and even IPv6 to IPv4 trading, catering to the diverse needs of organizations in the IPv4 market.

While the InterLIR marketplace offers a valuable alternative to traditional IPv4 brokers

it’s essential to consider the unique advantages and limitations of each approach when deciding which method best suits your organization’s needs.

Here are some factors to consider when choosing between an IPv4 broker and the InterLIR marketplace:

  1. Support: IPv4 brokers provide personalized support and guidance throughout the transaction process, while the InterLIR marketplace is a more self-guided platform. Consider whether your organization would benefit more from the hands-on assistance provided by a broker, or if you have the necessary expertise in-house to navigate the marketplace.
  2. Negotiation: Brokers can help with price negotiations and facilitate mutually beneficial agreements, whereas the InterLIR marketplace relies more on the buyer and seller to negotiate directly. Determine whether your organization has the skills and resources to negotiate effectively on its own.
  3. Risk mitigation: While both brokers and the InterLIR marketplace adhere to RIR policies and regulations, brokers may provide an additional layer of risk mitigation through their legal and technical expertise. Assess the level of risk associated with your transaction and decide if a broker’s added value is worth the investment.
  4. Market insight: Experienced brokers possess deep knowledge of the IPv4 market, which can be invaluable when determining the value of an IPv4 address block and making informed decisions. The InterLIR marketplace offers transparency in pricing and availability but may not provide the same level of market insight as a broker. Weigh the importance of market intelligence in your decision-making process.
  5. Time and resources: While the InterLIR marketplace streamlines the transaction process through automation, managing the transaction internally may require a greater investment of time and resources from your organization. Consider the availability and expertise of your in-house team when deciding which option is more efficient and cost-effective for your organization.

Ultimately, the choice between partnering with an IPv4 broker and using the InterLIR marketplace will depend on your organization’s specific requirements, resources, and preferences. By carefully evaluating the advantages and limitations of each option, you can make an informed decision that best aligns with your organization’s IPv4 address acquisition strategy.

Exploring InterLIR Auctions: A Platform for Buyers, Sellers, and Brokers

InterLIR auctions provide a dynamic and interactive platform for IPv4 address owners, brokers, and potential buyers to post deals, browse available address blocks, and bid on transactions. This marketplace expands the opportunities for participants in the IPv4 market to connect and engage in competitive, transparent, and efficient transactions.

Here are the key features and benefits of InterLIR auctions:

  1. Auction format: The auction format encourages competitive bidding, helping sellers obtain the best possible price for their IPv4 address blocks and buyers to secure deals at competitive rates.
  2. Inclusive platform: InterLIR auctions are open to IPv4 address owners, brokers, and potential buyers alike, creating a diverse and accessible marketplace that accommodates various stakeholders in the IPv4 market.
  3. Visibility: Deals posted on InterLIR auctions receive widespread exposure to a large audience of potential buyers, increasing the likelihood of a successful transaction.
  4. Real-time bidding: The auction platform allows buyers to place real-time bids on IPv4 address blocks, ensuring that the most up-to-date pricing information is available to all participants.
  5. Customizable listings: Sellers and brokers can tailor their listings to highlight the unique features and advantages of their IPv4 address blocks, helping to attract the right buyers and facilitate a successful transaction.

By participating in InterLIR auctions, organizations can enhance their IPv4 address acquisition or divestment strategies, leveraging the platform’s competitive and transparent environment to secure the best possible deals. However, it’s important to consider the unique dynamics of InterLIR auctions and how they may differ from other transaction methods, such as working directly with an IPv4 broker or engaging in private negotiations.

When deciding whether to participate in InterLIR auctions, consider the following factors:

  1. Auction dynamics: The competitive nature of auctions can drive up prices, but it can also result in favorable deals for buyers, depending on the level of interest and bidding activity. Assess your organization’s risk tolerance and willingness to engage in auction-style bidding.
  2. Market exposure: While InterLIR auctions provide increased visibility for your IPv4 address listings, this exposure may also attract more competition among buyers. Determine if the benefits of increased exposure outweigh the potential for heightened competition.
  3. Resource allocation: Participating in auctions may require more time and resources from your organization, as you will need to monitor bidding activity and adjust your strategy accordingly. Consider whether your team has the capacity to manage the auction process effectively.
  4. Expertise: Navigating the auction platform and bidding process may require specialized knowledge and experience. Evaluate your organization’s expertise in managing auctions and consider partnering with a broker who can provide guidance and support if needed.

In conclusion, InterLIR auctions offer a unique and valuable platform for organizations to engage in competitive and transparent IPv4 address transactions. By understanding the dynamics of the auction process and how it compares to other methods such as working with an IPv4 broker or using the InterLIR marketplace, you can make an informed decision about the best approach for your organization’s IPv4 acquisition or divestment strategy.


Whether you decide to work with an IPv4 broker, use the InterLIR marketplace, or participate in InterLIR auctions, it’s essential to stay informed about the evolving IPv4 address market and be proactive in planning for the eventual transition to IPv6. By doing so, you can ensure that your organization is well-prepared to navigate the challenges and opportunities presented by the IPv4 address scarcity and the ongoing shift to a more sustainable internet addressing system.

What is IPv4 header format ?

Every IPv4 packet starts with the IPv4 header, a fixed-size data structure. Networking hardware uses it to route the packet to its destination because it contains a range of crucial data. The fields in the IPv4 header are listed below in the following order:

  • Version (4 bits) – This field indicates the version of the IP protocol being used. This parameter is always set to 4 for IPv4 packets.
  • Header Length (4 bits) – This parameter indicates the length of the header in 32-bit words. This number might be anywhere between 5 and 15, as the header may have optional fields.
  • The Type of Service (8-bit) field is used to describe any unique handling needs as well as the packet’s priority.
  • Total Length (16 bits) – This field indicates the overall length of the packet in bytes, including the header and data.
  • Identification (16 bits) – This field is utilized for fragmentation and reassembly. Each packet is given a special identification number that can be used to put together broken packets.
  • Flags (3 bits) – These bits are used to regulate fragmentation. The “More Fragments” (MF) flag is set in all fragments save the final one, while the “Don’t Fragment” (DF) flag specifies that the packet shouldn’t be fragmented.
  • Fragment Offset (13 bits) – This field indicates the offset of the data in the packet, relative to the beginning of the original unfragmented packet.
  • The maximum number of hops a packet is permitted to make before being deleted is specified in the Time to Live (8-bit) field.
  • Protocol (8 bits) – This field identifies the protocol used in the data section of the packet, such as TCP, UDP, or ICMP.
  • Header Checksum (16 bits) – This field is used to check the integrity of the header.
  • The IP address of the sender is contained in the Source Address (32 bits) column.
  • The IP address of the recipient is contained in the destination address (32 bits) field.
  • Options (variable) – This field is optional and can be used to include additional information, such as security and routing information.

The IPv4 header format has now been briefly explained.

Subnet Mask: What it is and How it Works?


A subnet mask is a critical component in computer networking that defines the boundaries of a network. It is a numeric code that tells network devices which part of an IP address is used to identify the network and which part is used to identify the individual device. In simpler terms, the subnet mask is used to separate an IP address into two parts: the network address and the host address.

In this article, we will delve deeper into what a subnet mask is, how it works, and why it is essential in computer networking.


  1. What is a subnet mask?
  2. How does a subnet mask work?
  3. Types of subnet masks
  4. How to calculate a subnet mask
  5. Subnetting and subnet masks
  6. Why are subnet masks important?

What is a subnet mask?

A subnet mask is a 32-bit code that is used to separate an IP address (check into two parts, namely the network address and the host address. The network address is used to identify the network, while the host address is used to identify the individual device within the network.

How does a subnet mask work?

A subnet mask works by determining which part of an IP address is used to identify the network and which part is used to identify the host. The subnet mask does this by using a binary code that is applied to the IP address. The binary code has a series of 1’s and 0’s that determine which part of the IP address is used to identify the network and which part is used to identify the host.

Types of subnet masks

There are two types of subnet masks: classful and classless . Classful subnet masks are used in traditional networking and are based on the IP address classes, whereas classless subnet masks are used in modern networking and are based on the variable-length subnet masking (VLSM) technique.

How to calculate a subnet mask

To calculate a subnet mask, you need to know the number of bits used to identify the network and the number of bits used to identify the host. The number of bits used to identify the network is determined by the subnet mask. The number of bits used to identify the host is the remaining bits of the IP address.

Subnetting and subnet masks

Subnetting is the process of dividing a network into smaller subnetworks. Subnet masks are used to determine the boundaries of these subnetworks. Subnetting is essential in computer networking as it enables network administrators to manage network traffic more efficiently and provides additional security measures.

Why are subnet masks important?

Subnet masks are important because they determine the boundaries of a network. By defining these boundaries, network administrators can manage network traffic more efficiently and provide additional security measures. Subnet masks are also used to divide a network into smaller subnetworks, which allows for more efficient use of network resources.


Q: What is CIDR notation?

A: CIDR notation is a compact way of representing an IP address and subnet mask in a single notation. It uses a slash (/) followed by a number to represent the number of bits used to identify the network. For example, represents an IP address of with a subnet mask of

Q: How to use CIDR notation?

A: CIDR notation is used to simplify the representation of IP addresses and subnet masks. It is commonly used in networking to configure network devices and to represent IP address ranges.

Q: What is the difference between a subnet mask and a default gateway?

A: A subnet mask and a default gateway are both used in networking, but they serve different purposes. A subnet mask is used to define the boundaries of a network, while a default gateway is used to direct traffic from one network to another.

Q: How to find the subnet mask of a network?

A: To find the subnet mask of a network, you can use the ipconfig command in Windows or the ifconfig command in Linux or macOS. You can also check the configuration of your router or network device to find the subnet mask.

Q: How to change the subnet mask of a network?

A: To change the subnet mask of a network, you will need to access the configuration settings of your router or network device. From there, you can change the subnet mask to the desired value.

Q: What is a broadcast address?

A: A broadcast address is a special IP address that is used to send a message to all devices on a network. It is typically the last address in a network and is represented by setting all host bits to 1 in the subnet mask.

Q: What is the maximum number of hosts per subnet?

A: The maximum number of hosts per subnet is determined by the number of host bits in the subnet mask. The formula for calculating the maximum number of hosts is 2^n – 2, where n is the number of host bits in the subnet mask.

Q: How to calculate the number of subnets in a network?

A: To calculate the number of subnets in a network, you need to know the number of bits used to identify the subnets in the subnet mask. The formula for calculating the number of subnets is 2^n, where n is the number of subnet bits in the subnet mask.


In conclusion, subnet masks are a critical component in computer networking that define the boundaries of a network. They are used to separate an IP address into two parts, the network address and the host address, and are essential in subnetting, managing network traffic, and providing additional security measures. Understanding subnet masks and their role in computer networking is crucial for network administrators and IT professionals to configure and maintain computer networks effectively.

Comprehensive Guide to IP Blocklists: Protecting Your Network and Enhancing Security

Table of Contents

  1. Introduction
  2. Types of IP Blocklists
  3. How IP Blocklists Work
  4. Advantages of Using IP Blocklists
  5. Disadvantages of IP Blocklists
  6. Choosing the Right IP Blocklist
  7. How to Implement an IP Blocklist
  8. Monitoring and Updating IP Blocklists
  9. Conclusion

1. Introduction

In today’s digital landscape, protecting your network and enhancing security is crucial. One effective strategy for mitigating threats is using IP blocklists. This comprehensive guide will provide you with in-depth information on IP blocklists, their types, how they work, and their pros and cons. Moreover, we will offer insights on selecting the right blocklist and implementing it effectively.

2. Types of IP Blocklists

IP blocklists can be categorized into three main types:

Public IP Blocklists

These blocklists are open to the public and commonly maintained by security organizations, ISPs, or cybersecurity researchers. They contain known malicious IP addresses and are regularly updated.

Private IP Blocklists

These are customized and maintained by organizations for their specific security needs. Private IP blocklists usually include addresses that have been flagged for potential threats within the organization’s network.

Commercial IP Blocklists

Commercial blocklists are offered by cybersecurity companies and provide enhanced security features, including advanced threat intelligence and regular updates. They often come with a subscription fee but offer a higher level of protection.

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3. How IP Blocklists Work

IP blocklists function by preventing communication between an organization’s network and potentially harmful IP addresses. Here is a step-by-step explanation of how IP blocklists work:

  1. A blocklist is implemented in the organization’s security infrastructure, such as firewalls, intrusion prevention systems (IPS), or security gateways.
  2. When an incoming request or connection attempt is made, the security system checks the originating IP address against the blocklist.
  3. If the IP address is found in the blocklist, the connection is denied, and the attempt is logged for future analysis.
  4. If the IP address is not listed, the connection proceeds to the next stage of the security process.

4. Advantages of Using IP Blocklists

IP blocklists offer several benefits, including:

Enhanced Network Security

By blocking known malicious IP addresses, blocklists significantly reduce the risk of cyber threats, such as DDoS attacks, malware, and phishing.

Reduced Spam

Blocking IP addresses associated with spam helps in minimizing unwanted emails and maintaining a cleaner inbox

Improved Network Performance

Blocking unwanted traffic from malicious IP addresses can lead to better network performance by freeing up bandwidth and reducing unnecessary load on network resources.

Proactive Defense Mechanism

IP blocklists provide a proactive defense against cyber threats by preventing communication with known malicious sources, rather than relying on reactive measures after an attack has occurred.

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5. Disadvantages of IP Blocklists

Despite their advantages, IP blocklists also have some drawbacks:

False Positives

It is possible that legitimate IP addresses may be mistakenly included in a blocklist, leading to unintentional blocking of valid traffic.

Dynamic IP Addresses

Attackers can use dynamic IP addresses to bypass blocklists by changing their IP addresses frequently, rendering the blocklist less effective.

Maintenance and Updates

Keeping blocklists up-to-date and accurate requires regular maintenance, which can be time-consuming and resource-intensive.

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6. Choosing the Right IP Blocklist

Selecting the right IP blocklist depends on your organization’s specific needs and resources. Here are some factors to consider when choosing an IP blocklist:


Ensure that the blocklist covers a wide range of malicious IP addresses, including those associated with spam, malware, and DDoS attacks.

Update Frequency

Choose a blocklist that is frequently updated to stay current with the latest threats.


Consider the reputation of the blocklist provider and their track record in the cybersecurity industry.


Evaluate the cost of the blocklist, including any subscription fees, and weigh it against the benefits it provides.

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7. How to Implement an IP Blocklist

Follow these steps to implement an IP blocklist in your organization:

  1. Choose a suitable IP blocklist based on your organization’s requirements and resources.
  2. Integrate the blocklist into your security infrastructure, such as firewalls, intrusion prevention systems, or security gateways.
  3. Configure the security system to use the blocklist for filtering incoming traffic.
  4. Test the implementation to ensure it is functioning as expected and not causing any disruptions to legitimate traffic.
  5. Monitor the system to identify any potential issues and maintain the effectiveness of the blocklist.

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8. Monitoring and Updating IP Blocklists

Regular monitoring and updating of IP blocklists are crucial to maintaining their effectiveness. Here are some best practices for managing IP blocklists:

Regular Updates

Update the blocklist regularly to keep up with the latest threats and ensure it remains effective.

Monitor Logs

Review logs generated by the security system to identify any false positives or other issues that may arise due to the blocklist implementation.

Fine-tune Configuration

Adjust the security system’s configuration as needed to minimize false positives and optimize performance.

Stay Informed

Stay informed about the latest cybersecurity threats and trends to ensure that your blocklist remains relevant and effective.

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9. Conclusion

IP blocklists are an essential tool in enhancing network security and protecting against cyber threats. By understanding the different types of blocklists, how they work, and their advantages and disadvantages, you can make an informed decision on the right blocklist for your organization. Implementing and maintaining an effective IP blocklist requires ongoing monitoring and updating, ensuring that your network remains secure against evolving cyber threats.

IPv4 Pricing Trends

Experts and target audiences noticed an unusual turn in pricing for IPv4 addresses. For the last few years, addresses for blocks less than (up to/17) were more expensive than large ones (starting from /16). From the middle of 2020 til August 2021, the pricing gap was ranging widely (2,4% – 17,5%). Many sellers started breaking huge blocks to increase their income.

In 2022 the situation turned vice versa. Huge blocks raised in price. Until May this trend was stable. As the large blocks became costly, smaller blocks became cheaper. The tendency of the previous year caused the general pricing diversity. From 1,1% (end of 2021) to 7,5% (April 2022).

To stay at a competitive level, it’s important to monitor the pricing trends in 2023 24/7. It will help to correct the strategy and meet the market terms. For example, a customer may think about the profit of purchasing four /18 cheaper or one /16. The last is more convenient, the deal will be held quicker. The transfer fee will be charged only once.

If a seller has /16 but uses only its small part (for example, a/20) comes a question: what is it better to sell? The entire block or its passive space? Is it better to divide the address into smaller parts?

The smart strategy depends on the current market situation. Regular changes need regular analysis.

Fees for IP Address in 2023

Every belonging or something we control can be called property. For example, real estate objects or land we can call regular property. There are also intangible properties (names of brands, logos, unique content, etc.). This category is rather complicated.

Management or ownership of intangible objects differs from those of physical assets. Thus, internet numbers or names can be provided on contract terms for a certain period of time or without time limits. A contracting party can proceed with a registration procedure – to become a member.

The Internet Assigned Numbers Authority (IANA) is the main online registry. It heads all the other registers with web protocols, numbers, and names. For example, online traffic is working on HTTP protocol. In its turn, those protocols are using ports. No other protocol can work on the registered port. So, registration is an important condition. Lists with all the protocols are published on IANA. There one can find updated information.

Each register is managed. Managers have to cover the spending. That’s why registration is paid. Users pay for numerous network resources, including IPs, names, etc.

Presently, there exist five registries functioning on a regional level for Number Resources. They charge customers different fees.

Roots Of System Development

When the internet was an innovation, its initial organization DARPA signed a contract with the Information Sciences Institute at the University of California. They covered IANA’s responsibilities. They made the list of identifications according to web locations (interfaces). These numbers are known as IP addresses. Technical progress required particular changes.

The internet was actively developing. From 1992, commercial traffic moved online. It was in 1992. The result of such policy change turned into appearing in two directions. On the one hand, networks worldwide started using internet connections. On another hand, the American government tried to avoid spending on supporting the centralized base of domains and IPs. The government started activities to turn internet administrative needs into a private sector. At the end of 1992, RFC 1446 offered an initiative to divide the registration for serving global users more diversely.

The cooperation of network operators was aimed at changing the principles of Internet Number of Resources. The registry had to become more regionalized. In Europe, the RIPE NCC appeared (in April 1992). APNIC (Asia-Pacific region) started its way in 1993.

In the USA the initial step for privatization was the creation of the American registry for internet numbers ARIN (1997).

Today there are five existing Regional Internet Registries. RIRs’ function is to run IP registrations. In several regions, National Registries (NIRs) work to support RIRs.

NIRs are operating under the supervision of RIRs. The difference is that they first serve customers in a certain country. In such a way, operators can communicate in the language they prefer, work under the law on the local level, and use the local currency.

What’s Paid?

Fee terms and schedule is individual for each RIR/NIR. Customers are charged for three basic aspects:

  • a membership charge that provides the right to register IP, and participate in voting;
  • a non-member fee to use a registry IP function for an organization;
  • a transaction charge for all kinds of transfers.

Most organizations are only charged as membership registrants or non-membership customers.

As a member, an organization can implement RIR management activities by voting. Those organizations that want to achieve smooth functioning, are taking serious responsibility. There are some restrictions for some organizations that don’t allow them to take a membership with other companies. There are also those who don’t want to lead management.

Setting Fees by RIR

RIR members choose a board on elections. The board suggests and sets the charge schedule once a year. Some regional RIRs are allowed to set fees by themselves. According to standard procedure, the board is the one to offer an idea. The final decision is taken after voting.

Setting IP fees can seem a boring task for some people.

Any changes concerning fees (sizes, ways) become the center of webspace attention immediately.


In the following guide, we’ll demonstrate the charge of the RIRs in 2023. The information concerns 65,000 IPv4 addresses (a class B).

Different RIRs have different fees. It concerns both the size and the schedule. Moreover, the difference can be huge. For example, NCC RIPE canceled the differentiated charge. Instead, they set low commission that is compulsory for everyone. APINIC sets base charge. Extra fees or discounts depending on the IP space and the location of the organization.

The fees are reviewed once a year. In 2023 payments will rise.

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There are seven levels of fees for members and the same quantity of levels for the number of resources under its management. Costs vary from $3,150 to $48,400.

For non-members, the fees are $200-2,500 per year.

According to Afrinic’s policy, transfers are available only on emerging and acquisition terms.


It sets the charge for base membership – at 1,180 AUD. Further payments depend on the amount of IP space that belongs to the registrant. Payment is reduced twice for the poorest countries.

The minimal annual charge is 1,180 AUD. Price for A/16 (Class B) is 9,626 AUD.

To sign-up, you have to pay 500 AUD.

Transfers are paid 20% of the membership charge per year.


In 2022, the company set a fee limit for legacy resource owners to $150. The plan was to raise the sum by $25 each year. There are eleven levels of charge for registered organizations assigned to the plan. Transfers cost $500.


23 charge levels for partners with membership. Payment is from $600 to $365,000. The first-time assignment may cost $2,500 or $5,000. It depends on the size. After that, there is a fixed cost per year – of $600.

Special offer – discounted fees paying for 30 days. Transfers are available with zero commission.


All the customers make payments on the same terms. In the previous year, the first-time registration cost 1,000 euros. Fees per year are 1,400 euros.

Transfers are free. Extra cash is divided between members.

IP Address Reputation

The network IP addresses vary from each other so network operators require expert guidelines. Daily, each of us gets suspicious letters on the email address that’s why the reputation of the sender is of high importance. In practice, senders’ identification on the basis of personal IP is a real challenge, and quite useless.

For years, the heads of email web systems ignored incoming correspondence sent from home internet IPs. By the end of 2021, the number of wired home network connections reached more than 1 million. Maintaining a database of reliable email users would be difficult. The main issue could be concerned with the differentiation between those numerous bots sending viral content or leading suspicious activities.

Thus, dedicated systems for email sending should be used. The duty of system administrators is to evaluate the reputation of those systems that are less numerous. There are various tools for such analysis.

Some indicators of IP address reputation are measured similarly.

It’s necessary to find out the following:

  1. Should the income mail come from this address?
  2. What’s the geo?
  3. Is there a malware infection on an IP?
  4. Is it using network users’ personal data without permission?
  5. Does it have an open proxy server to help the miscreants?

The Importance Of the Reputation for the IP

Setting IPs in accordance with equipment for their functioning on the webspace is only a part of the job. It’s not less essential to create a new spatial range of IP addresses.

Any remarkably wide range of IPs previously was used on another network. Despite the Regional or National Internet Registry will make a transfer to your company visible, those changes aren’t shown up immediately and automatically in most of the tracking tools. Thus, it’s necessary to update those systems so that they provide actual information concerning management, geographical location, and purpose.

The Scoring Algorithm for IP Reputation

To create a friendly reputation, it’s better to avoid sudden switching between users. An accurate and well-planned deployment will bring much better results. Using address space right before the transfer is risky – it may be spoiled. Leave it for some time, so it won’t join the blacklist. If your purpose will be the same that the previous user had, you’ll have to examine the databases on this subject.

Reputation is being tracked for IPs that are sending emails. This point should still be considered. To be aware of the current situation, one may join the Mailop community. In the best practical cases, host mailing data, lists, and discussions can be rather useful.

If you’re transferring IPs from another geography, and it will be available for consumer web clients, contact the company managing geodata for IP addresses (GeoIP). Consumer content can have a particular specification according to the market. It can be licensed. The managing companies are keeping the data access settings according to local or owner restrictions.

If the IP was used in a region with not the same language as yours, you may take advantage of the platforms describing the transfer. You can set the interface with any language you choose or that is the best for the target audience.

If you have another purpose for using the address than a former user, you need to ensure that the channels that work with reputation contain updated information.

If you have another purpose for using the address than a former user, you need to ensure that the channels that work with reputation contain updated information. Then you won’t be recognized as a suspicious user and your network won’t appear in the block list. For example, IPs that were used for network access by subscribers before can be repurposed for cloud server means. For sending trusted correspondence, you need to remove the IP from various lists and databases. If the address isn’t meant to send emails, it will definitely be blocked.

Reputation Monitoring Tools

Databases with Geo IP are available on Brothers WISP. This resource can be useful to the consumer addresses in case the regional services restrict the content distribution. For example, gaming sites or resources with video content.

The lists of recommended networks are led by the project called Spamhous. On their basis, it’s easier to evaluate the traffic quality.

The Cleanup Procedure

Check the reputation of the new IP range at influential sources. Update if required. It’s necessary to find out the lists considering the aim to reach. To change the outdated information about the registrant, you should contact the administration team. Let them know about any change – geo, purpose, etc.

The procedure is time taking. It’s better to put time into your deployment planning. Some teams prefer to solve the issues as they come.

How to Lease IPv4 Addresses in 2023

IPv4 addresses are a limited resource that may run out sooner than you think! Leasing IPv4 addresses can ensure your business has the IP space it needs when leasing IPv4 addresses in 2023. If you wait until the last minute, your business could be left behind, so start planning now! This guide will help you understand what IPv4 addresses are and how they work and how to lease them.

Why should you lease IPv4?

You may want to lease your IPv4 addresses if you don’t need all of them at once or ever. For example, leasing makes sense if you’re running a small business and don’t have many employees but need more than one public IP address. An Internet Protocol version 4 (IPv4) address is a numerical label assigned to each device that connects to a computer network that uses IP. The numbering system uses four numbers separated by periods (also called an IP address) and is expressed in dotted-decimal notation, such as

Some numbers are reserved for a particular use, so they can’t be used leased or purchased from a service provider. Typically these are low-numbered addresses with special meanings, including 0 and 255, although it varies depending on country regulations.

How much will leasing cost?

 This year, even that pool has been drained with only millions of addresses available for allocation. RIRs will hand out the remaining IP addresses in chunks of 256. By 2023 we’ll have run out, and there won’t be any more freely available addresses unless some alternative protocol or system is adopted or created, for example, IPv6.

 The problem is that not everyone wants to use IPv4 addresses and is searching for an alternative. There are some intriguing ideas for alternative protocols (see Web 3.0). Still, it will be years before any of those can come into play, so getting your hands on an IP address from a network provider will be necessary. The good news is that you can acquire these well ahead of time. The bad news is there’s no guarantee that you’ll ever actually need them. It all depends on how fast other alternatives come into play and how many devices you own.

 There are a few ways to lease an IP address from a network provider. For example, Google offers IP addresses that are leased as cloud services. Google Cloud Interconnect provides customers with public IP addresses on three continents and options for private interconnects between data centers that ensure performance and security. That is just one of many alternatives to acquiring your blocks of IP addresses when they become available through providers like T-Mobile and Interlir.

Why would anyone lease unused IP addresses?

It depends on how much space you need.

The Internet Protocol is one of many protocols (series of rules) that govern the communication between a computer and a network. The Internet Protocol defines an IP address as a unique string of numbers that can be used to identify any device on an IP network. For example, your computer has an individual IP address that allows it to connect with web services you’ve requested or video chat with friends. But it turns out we are running out of those addresses, and soon there won’t be enough for everyone’s devices. So, here’s how you lease IPv4 addresses ahead of time, so they’ll be ready when you need them.

If you’re not using your IP addresses, why not lease them out to businesses that need additional addresses? In addition to increasing your profits on unused assets, leases generate recurring income every month. You can buy and lease your unused IP addresses from anywhere in the world: Germany, USA, Africa. To do this, you need to create a sub-allocation pool of one or more contiguous /8s (256 to 65,536 individual /24 blocks). The person leasing an address from you will pay for a single allocation from that pool, which is how they receive their desired number of IP addresses. When leases expire after five years (or earlier if either party decides), you’ll be able to use those blocks again for your purposes. This way, everyone wins! You can lease unneeded IP addresses and create a stream of recurring revenue; potential lessees get access to address space without waiting for a future round of IPv4 allocations; Internet users have uninterrupted access when transitioning from one leased block to another.

 Some might worry that allowing organizations to lease unused addresses will take away Internet users’ IP address space. Still, leases typically last five years, after which organizations will receive a single allocation from your pool and have their leased blocks returned to you. So there’s no long-term impact on future IP allocations. If anything, leases are an incentive for ISPs and businesses with large stockpiles of unused addresses to release them back into circulation rather than hoard them. This additional availability of IPv4 addressing space should keep IP address assignment needs—and costs—from escalating for many years. In other words, getting creative about allocating or renting out your IP addresses can generate extra revenue without affecting Internet users’ ability to get online.

 So why would anyone lease unused IP addresses? In many cases, there’s no downside. You don’t lose control of your unneeded IP addresses since you’ll receive back all of them plus a single allocation from your pool after five years (or sooner if either party decides). Plus, you can generate recurring revenue every month without selling or transferring your existing address space. It’s a win-win for everyone involved! If you’d like more information about leasing IPv4 addresses and setting up an allocation from one or more contiguous /16s—or if you need assistance setting-up a sub-allocation pool in RIPE DB—don’t hesitate to get in touch with Interlir. We’re here to help!

 Contact us if you’re interested in leasing your unused IP addresses and don’t know where to start. We can provide more information about how sub-allocation pools work, answer any questions you may have, and give you assistance getting started. And remember: You don’t need to use RIPE DB for a sub-allocation pool; if you prefer using legacy RIPE tools instead, we can set that up for you. Suppose you’re new to leasing IP addresses or entering into such agreements. In that case, we also offer a  training session that covers all aspects of managing leasing space and what happens when leases expire.

Who are some of the organizations leasing IP address space?

Germany, China, and India have all been leasing (renting) IP address space to ISPs since 2010. An emerging industry of providers rents small or large blocks of IP addresses every month. This short-term rental option lets you cover your immediate needs without a long-term commitment—ideal for organizations that might not need more than 1-2 blocks of space in any given year. Rental prices vary depending on the provider and the time/size of the block required.

IPv4 Provider is a company that leases out IP addresses. They have become more popular as organizations realize they can cover their short-term needs without a long-term commitment. In addition, you can rent/buy an ipv4 block cheaper; some providers offer discounts for renting multiple blocks of IP addresses. For example, if you lease two blocks of 1024 IP addresses each, you might get a 3% discount on your total price. This can make leasing an attractive option for smaller organizations with more immediate needs but who don’t want to commit to a long-term contract or pay higher prices for permanent IP address space. The provider typically handles all maintenance and technical support related to your leased IP address space, so there’s no need for you to set up or maintain your equipment.

What advantages does leasing provide?

If you’ve found a block of IP addresses, you’d like to rent or lease, it’s time to start inquiring about pricing and rates. The prices can change often based on availability and location but increased 100% since 2021 to 50$ per IP. These services offer savings, but they’ll also allow you to save space by bundling multiple IP address ranges into one lease. For example, if your company is looking for a /16 (that’s 65,536 unique IP addresses), you could quickly be paying millions USD when purchasing that many IPs outright—and then still have a lot of unused IP space.

 Renting IP addresses isn’t just beneficial for businesses and government entities who need space but don’t want to commit to long-term leases. Even homeowners are turning to IP address leasing and rental services as Internet connections become increasingly vital—and often nearly necessary—too many facets of life today. A typical home may require a static public IP address for its primary connection and more ephemeral (often dynamic) IP addresses for wireless routers and home networks. No matter your needs, you can lease an IP address with any provider from all over Europe and other regions worldwide.

Is there an alternative solution?

Many ISPs, organizations, and other entities that currently get IP addresses from organizations like ARIN or RIPE will be interested in leasing IPv4 addresses when they become available for lease. New networks are also likely to emerge internationally—primarily in Germany, which has already begun preparing a leasing market; time will tell whether both organizations and individuals embrace it outside of Germany. If you’re planning on launching a new network and want to quickly gain access to a large block of IP addresses (for instance, if you’re a data center company), then your best bet is probably going to be renting them on an international level.

 From a cost perspective, leasing IP addresses is often cheaper than buying a large block of static IP addresses. Organizations that rely on public Internet backbones for their business operations may also gain access to new address blocks through service providers and regional network operators. Most importantly, moving away from static leases towards dynamic pooling may also help ensure that we don’t run out of IPv4 addresses in five years! When you lease an address, it becomes part of a pool that your ISP or provider can assign to different devices at different times, preventing anyone particular device from consuming too many individual IP addresses. ISPs could even use lease pools for everyday Internet users – if you rent a static IP address today, you probably have hundreds of unused addresses. 

 Your best option for accessing a large pool of IP addresses for both new and established networks will be renting addresses from an existing network operator. As mentioned above, Germany has already built up a significant market for leasing IPv4 addresses; operators are now using some unused address blocks to lease out to other organizations. It’s likely that Germany, and potentially other countries, will create more leasing markets as more and more IP addresses become available. But whether or not your country makes an IPv4 address-leasing market, you’ll have no trouble accessing them internationally – many ISPs already offer leased address blocks. In contrast, major national providers like Comcast, Deutsche Telekom, NTT Communications, and Singtel have all said they will rent out different IP addresses.

Rent IPv4 with Interlir Marketplace

To lease an IPv4 address, you have two options: You can sign a contract with Interlir or use our marketplace platform. Leasing an IP address through Interlir gives you more flexibility, but it also requires that you sign a contract, in which lease time will be indicated. If you choose to rent an address from our marketplace, Interlir handles all of your payments and any disputes that may arise during your lease period (see below for details). Tell us how many addresses you need, and we’ll take care of everything else! Our leasing system is secure and reliable—and it makes leasing IPv4 as easy as possible. No matter which option you choose, leasing an IPv4 address from Interlir allows you to do what’s most important: focus on running your business instead of worrying about whether there will be enough available in 2023. Cost to buy ipv4 addresses is fair. Our support includes documents verification, data updates, consulting, the RIPE database updates, interaction with the RIPE NCC.


IPv4 rental with Interlir is fast and easy; tell us how many IP addresses you need, and we’ll take care of everything else! In addition, you can use the Interlir platform to rent only those addresses you need. This is particularly useful if you want more IP addresses but not enough for a full /16 or /20 allocation.

With our platform, you don’t have to worry about wasting any IP addresses by paying for an entire block that won’t meet your needs in 2023.

How do I rent IPv4 through a marketplace?

Since 2020, I’ve been working on InterLIR, the project to help the community obtain limited IPv4 resources at a reasonable cost.

Here’s my take on the IPv4 rental process with marketplaces.

To rent an IPv4 network from a marketplace, you will need to follow these steps:

1. Find a reputable marketplace

IPv4 rent is the temporary assignment of IPv4 addresses by the owner to another organisation.

2. Browse the marketplace’s listings to find an IPv4 network

3. Contact the seller to verify the availability of the IPv4 network and to negotiate the terms of the rental.

4. Once you have reached an agreement with the seller, you will need to provide them with the necessary information and documentation to complete the rental.

5. After the seller has verified your information and processed your payment, they will provide you with the necessary details to access and use the IPv4 network.6. Once you have access to the IPv4 network, you can begin using it for your business or personal needs.