Tuesday 12th August, 2014, has been marked as “512KDay”, the day the global Internet broke under its own weight. The Internet has been growing at a vast rate and 512K routes have always been noted as a significant number of routes on the routing table. On Tuesday 12th August, 2014, the 512K mark was passed.
Why 512K? 512K (or to be exact 524,288 or 2-to-the-19th power), is the maximum number of routes supported by the default TCAM configuration on certain aging hardware platforms. TCAM (Tertiary Content Addressable Memory) is where the routing tables are stored. On the 12th as the total number of routes passed 512K, the devices could not hold all of the necessary routes in memory and thus crashed.
To some this may have come as a shock, however to most, this is not a surprise. It has been known for a number of years that this time would come, and a simple ‘work around’ was advised, users were even sent reminders in May 2014 to make the necessary changes.
By default the devices in question are pre-allocated with memory capacity that can support 512K IPv4 routes, which is actually only half of their TCAM memory. The second half of the TCAM memory is allocated to IPv6/MPLS routes. The work around is a simple reboot and reconfiguration, the half of the TCAM allocated to IPv6/MPLS routes can be altered and added onto the allocated to IPv4 route allocation.
A number of ISP’s, and consequently their customers, experienced issues on the Tuesday as a result of not carrying out necessary reboots or upgrades to their network when advised. As part of Fluidata’s core network upgrade in 2012, our network design took into account the forecasted routing table issues, and thus the issues that many ISP’s experienced on 14/08/14, was not one that we experienced.
It is left to ask, when will the Internet, again, brake under its own weight? News today announced that millions of children in England will begin a "tough" new national curriculum when they return to school this week, the curriculum involves improved computing lessons that will teach pupils how to write code. The BBC states that pupils aged five to seven will be expected to "understand what algorithms are" and to "create and debug simple programs". By the age of 11, pupils will have to "design, use and evaluate computational abstractions that model the state and behaviour of real-world problems and physical systems". An increase in knowledge and the ever improving development of The Internet of Things leaves us thinking it will be sooner than expected.