Internet routing data: real-time analysis

01 April 2011 |


By tracing and monitoring internet routing, companies such as Renesys can gather a comprehensive view of internet connections worldwide, allowing the company to provide a real-time analysis of any changes that occur to the internet.

How is it possible to monitor and trace internet routing worldwide?


Monitoring and tracing internet routing worldwide relies on border gateway protocol (BGP) peering. Renesys has established peering relationships with 350 network service providers from every continent across the globe – bar the small cold exception of the Antarctica – with the sole purpose of route collection. Using this, the company has compiled a routing map of how the industry intends for internet traffic to be delivered.

The company also operates BGP route collectors at a number of locations around the internet, which gives it the ability to physically measure trace routers to establish if internet traffic is in fact being accurately routed.

Using both sets of data, Renesys has accumulated a database of every routing change that it has observed to occur to the internet in the last 10 years.

What benefits can monitoring internet routing bring during an internet crisis?


As networks connect to a larger interdependent number of customers, partners and third-party networks, the risk to businesses on the public internet from external forces or events has increased, making the need for monitoring even more paramount.

In January 2008, for example, two submarine cables providing much of the capacity into the Middle East and the Indian subcontinent from the west were damaged. Some countries and a few providers were knocked off the internet completely, while the loss of connectivity in general was extensive and widespread.

Intense pressure to restore service to local governments and businesses ensued, as global and regional providers with surviving capacity into the region hurried for new customers. Renesys was able to provide a full report of the winners and losers after it examined the impact of the cable cut in five countries. In India, for example, the likes of Sprint, Cable & Wireless, Deutsche Telekom, BT and Verizon largely failed to restore connectivity to their networks, while AT&T and Flag also lost a lot of networks. The big winner was SingTel, gaining over 200 networks, followed by Level 3, picking up over 100.

How can internet routing data be used to facilitate the growth of domestic internet exchanges?


Internet routing data can be particularly beneficial for emerging countries looking to develop local peering. In the western world, domestic internet exchange points have become common practice – allowing internet providers to save money by transiting traffic within their country rather than allow it to be long-lined out.

In emerging markets, customers still suffer from high prices and limited connectivity. Using data from BGP route collectors, Renesys can help internet providers identify other domestic service providers to interconnect with at local exchange points, which will eventually limit the amount of domestic traffic passing through international
connections.

As an interesting tangent: following the infamous closure of the internet during the Egyptian revolution in February 2011, lower latency appeared on some of the country’s internet routing – particularly on international links – when it was restarted. Essentially connectivity in the country improved slightly as a result of the ‘reboot’.

What other types of reports can be produced from monitoring internet routing?


Renesys provides an alarm system, which can alert customers to routing changes in networks. This could help, for example, with incidents such as when Pakistan’s PTCL began advertising a small part of YouTube’s assigned network in 2008.

In response to the government’s order to block access to YouTube, the incumbent telco advertised a route to its provider PCCW. As this was a more specific route than the ones used by YouTube, most routers would immediately choose to send traffic to PTCL for this particular slice of YouTube’s network. The result was that, whether by accident or design, the Pakistani company effectively hijacked YouTube’s range of internet addresses for 24 hours until PCCW switched them off.