
There was just one roadblock: Heidelberg was using about 4% of the IPv4 addresses in the block, both externally and internally. To clean or prepare the block for sale, they would have to ensure their network wasn’t publicly using any of the addresses in the block. Ultimately, Heidelberg needed to more efficiently use their IP address space by implementing network address translation (NAT) and port address translation (PAT) in their network. This was their biggest technical challenge in selling the block and it took a few months to implement. Once NAT was established, they converted about 80% of the in-use addresses in two weeks, while the remaining 20% were more of a challenge and took additional time.
After the University began cleaning the block, ensuring that no IP numbers were in use and that its reputation was good, Addrex listed the block for sale in its Marketplace in January 2020. By the end of March, just as the COVID-19 quarantines began, an interested company committed to buying the block and the closing process began, when the buyer and seller are privately introduced. Funds were placed in escrow at the end of April and a few weeks later, the transfer process was completed, and Heidelberg was able to fully fund several IT projects with the proceeds left over after accounting for the network redesign.
Mr. Nguyen had this to say about Heidelberg’s experience with Addrex and the Addrex Marketplace:
Heidelberg University worked with the Addrex team to sell our IPv4 blocks in the Addrex Marketplace. Addrex guided us through the complex transaction and made it a seamless and quick endeavor.
Based on their experience and knowledge of the IPv4 resale market, I sincerely recommend Addrex and their Marketplace services for both block recovery and as a sales venue. They were responsive, reliable, and trustworthy through the entire transaction.
– Hoa Nguyen, Vice President for Administration and Business Affairs, Heidelberg University
Addrex continues to work with colleges and universities to help them accomplish their funding goals in a challenging education environment through monetizing unused IPv4 numbers and supporting their network transformation.
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