They received the letter ‘L’. Then they received the letter ‘o’. And then, the system crashed. An hour later, effectively the time the system took to recover from the crash, they were able to receive the entire message – ‘Login’. That was the first time ever a message was sent over the network, that we know today by as the Internet- and in the true sense of the word, we ‘logged-in’ to a new age.
What started in 1969 as a link connecting only two machines, and then about 15 machines by the end of 1971, the ARPANET (Advanced Research Projects Agency Network, named after the agency that created it), has evolved over time, to take shape as a mesh of interconnecting crisscrossing links, allowing communication between billions of machines across the face of the earth- the Internet.
Over the course of the past 43 years the Internet has been evolving. The number of devices- computers, laptops, smart phones- that are interconnected over the worldwide network has grown at such a massive rate, that we have now run out of IP addresses – unique numerical identifiers assigned to each and every device on the network.
The IPv4 (Internet Protocol version 4), is the most extensively deployed communication protocol for routing of data packets over the internet. It was standardized in 1981, has been a prominent driving force behind the growth of the Information Age. With an address space of 32 bits – a trail of 32 zeros and ones in different combinations – the IPv4 boasted of a capability to address approximately 4.3 billion different devices.
On Feb. 3, the last five blocks of IPv4 addresses were assigned to each of the five respective Regional Internet Registries, the organizations that manage the allocation and registration of IP addresses in 5 regions of the world.
But with the number of internet-ready computers and devices increasing at a rapid rate, the enormity of this ‘pool’ of available addresses was soon to go up in smoke.
According to Rudra Dutta, an associate professor in the Department of Computer Science, this is not the first time the internet has run low on addresses.
“In the late 1980s, applications like the e-mail and hypertext started becoming popular, and the first popular web browser, Mosaic was released by NCSA (National Centre for Supercomputing Applications). The desktop computers were made cheap and available to all by the revolution brought about by Intel, and more and more people started attaching their computers to the internet,” Dutta said.
“Back then, IP addresses could be allotted only in chunks of 256 – the next available chunk size was 65536, and the next, 16,777,216. So many companies went for the larger size of IP address blocks to accommodate further growth, but this resulted in many IP addresses that were withdrawn from the pool in large blocks, but not assigned,” Dutta said.
To avoid wasting IP addresses in this manner, several techniques were implemented, namely Classless Inter-Domain Routing (CIDR), and Network Address Translation (NAT). These techniques helped largely in reverting temporarily, the risk of address exhaustion.
“Network address translation included subnetting, i.e. assigning one routable address to an organization, instead of connecting every computer in the organization to the internet,” Dutta said. This avoided wasting of addresses being assigned and helped delaying the rate at which the pool of addresses was being consumed.
According to Dutta, however, CIDR and NAT were only temporary fixes to the problem. The long term solution is adopting the next version of Internet Protocol: IP version 6, or IPv6.
Since the IPv4 address exhaustion crisis was foreseen, the Internet Engineering Task Force (IETF) came up with the new protocol in 1998 to address this concern. With an address space of 128 bits, IPv6 is capable of generating addresses for 340 undecillion (34 followed by 37 zeroes) devices on the internet.
“There will be a time in the future when all of the internet will work on IPv6. But this switch cannot happen overnight, it will take place over a period of many years,” Dutta said. “Will this change be observable? No, because there will be absolutely no change in the data that will be exchanged over the internet, the only change that will take place is the way in which it is handled by the devices.
“The depletion of the IPv4 allocation pool has been a concern for a long time,” Wenxu Zhao, a first year Masters student in electrical engineering, said. “It seems that transition to IPv6 is the best way to solve this problem in the long term. I have experienced IPv6 when I was watching WorldCup 2010 over internet, and it was pretty smooth and stable.”
The next time you ‘login’ to your Facebook or Gmail account, spare a thought for this revolution, the Internet, that has been taking shape for the past half a century. And it all started with one word – login.