Despite the few RIPE Atlas probes available in Latin America, it is possible to obtain interesting measurements about changes in the architecture of the networks on Internet.
An example of this is the recent addition of an extra node to the LACTLD anycast cloud, the organization that groups the top level domain names in our region. This cloud answers queries directed to its name “a.lactld.org” using the nearest node, from a pool of four nodes so far. The first 2 are located in Sao Paulo, Brazil (a1-gru and a2-gru); and the third one in Santiago de Chile (a3-scl). In late June, a fourth node was added in Buenos Aires, Argentina (a4-eze); which represented a great opportunity to make an analysis of the effect it has in terms of the anycast routing technology.
The anycast technology uses the Internet routing preferences to reach the nearest node of a cloud (topologically speaking). By doing so, there is a distribution of query load and an optimization of response times.
For this, a measurement was made days before activation of a4-eze using probes from the “RIPE Atlas” platform, from the European organisation RIPE, which is built on small devices called “probes” that are hosted by worldwide voluntaries. For this study were used available probes in the nearby countries of the new node: Argentina, Bolivia, Chile, Paraguay and Uruguay. From each probe was recorded the a.lactld.org cloud node that was reached, in addition to the time it took the resolution. 56 observation points were obtained.
Once the new node a4-eze was activated we repeated the same measurement, obtaining 10 of them which changed the node preference to Buenos Aires, being those affected by the new advertised route. All these probes obtained quite significant improvements in response times, between 16% and more than 80% in 4 nodes. Argentina and Paraguay probes were benefit.
Animation shows both moments, before and after activation of a4-eze. In red are the probes that changed their preference. Bullets are the nodes.
Moreover, to the extent that improvements in connectivity is achieved with higher capacity links and interconnection agreements between cities and local ISPs, these changes are automatically reflected in route redistribution, automatically selecting nodes that are better achievable. This adds to the continuous addition of new nodes from LACTLD to the cloud (it is planned soon have nodes in San Jose, Costa Rica and Montevideo, Uruguay), that also redistribute routes.
A great improvement for resilience, load balancing, security and availability for domain names hosted in the LACTLD anycast cloud.
“` City | Pre a4 | Post a4 | Delta | Improvement | Node Time | Node Time | | % Buenos Aires | a1-gru 100.139 | a4-eze 74.210 | 25.929 25.90 Buenos Aires | a3-scl 159.333 | a4-eze 3.014 | 156.319 98.08 Buenos Aires | a3-scl 212.462 | a4-eze 33.374 | 179.088 84.30 Córdoba | a3-scl 177.031 | a4-eze 17.956 | 159.075 89.86 Asunción | a3-scl 187.395 | a4-eze 156.668 | 30.727 16.40 Buenos Aires | a3-scl 210.249 | a4-eze 32.018 | 178.231 84.78 Buenos Aires | - - | a4-eze 21.581 | - - Buenos Aires | a1-gru 102.249 | a4-eze 75.597 | 26.652 26.07 Buenos Aires | a2-gru 101.875 | a4-eze 80.160 | 21.715 21.32 Buenos Aires | - - | a4-eze 74.864 | - - Buenos Aires | a3-scl 274.908 | a4-eze 137.122 | 137.786 50.13 Mendoza | a3-scl 307.482 | a4-eze 122.819 | 184.663 60.06
Pre a4 : Fri, 19 Jun 2015 18:53:59 GMT Post a4: Wed, 01 Jul 2015 17:48:07 GMT “`
Finally, this is the final situation considering all probes of the countries studied, with colors indicating the node that every probe is reaching:
Note: if you’re willing to host more probes in our region and help this kind of studies, please contact me! I’m an RIPE Atlas ambassador and have some for Chile, and also can put you in contact with someone in your country.
Disclaimer: I belong to the management group of the LACTLD anycast cloud, from NIC Chile.
(Maps from © OpenStreetMap contributors)