DNS Geographic Load Balancing

Deployed entirely as a service, DNS base GEO Load Balancing has revolutionized the global load balancing industry. With no hardware to deploy and no software to configure, TZO-GEO offers a level of simplicity and cost reduction which has never been available for global traffic management.

With as many as 25 participating servers or IP addresses, as an inbound DNS query comes in to the TZO DNS infrastructure, we lookup the Source IP address of the DNS query. We then match that source IP to a database of IP addresses and geographic longitude and latitude definitions. When a geographic location is found for the SA source address for the in bound DNS query, we then calculate which of the participating servers is closest in proximity to the originating DNS query. This all happens in milliseconds and poses no detectable latency to the standard DNS query.

Required Features for True GEOgraphic Functionality

• Global ANYcast Network Infrastructure
• edns-Client-Subnet, Client Side IP
• Multi-Point Monitoring
• Management and Visibility of Deployment

Global Anycast Network

TZO has a Global DNS Anycast based network. This is a requirement for true Geographically Intelligent Traffic Management.  Anycast provides the intelligence to be able to make decisions on where the closest DNS Name Server may be located. Most providers  DO NOT have this capability. TZO can make granular decisions based on Longitude and Latitude coordinates. This allows us to distinguish traffic from across town or across the globe.

GEO Precision – edns-Client-Subnet

TZO-GEO offers unmatched GEO-Precision by way of edns-client-subnet, client-side IP awareness. Typical geographic DNS offerings have no visibility as to the actual end point IP of the DNS request. The IP that gets used to determine the originating end point ends up being the IP address of the responding DNS Name server not the actual DNS end point. As such, the responding Name server could be anywhere in the world, thereby rendering the accuracy of the geographic DNS  ineffective or broken. This is a little known fact that other GEO DNS providers would rather not let out of the bag.

TZO-GEO has implemented edns-client-subnet, aka  client side IP. When TZO calculates the originating position of the requesting DNS end point we are doing so with the actual IP of the DNS end point, not the IP of the responding Name server. This makes TZO-GEO by far the most accurate geographic DNS service offering available today.

Virtual Geographic Load Balancing

With TZO-GEO we use a memory resident DB of all IP addresses on the globe and their Latitude – Longitude  definitions as to where they are located. With that in mind we can manipulate that DB and artificially put any IP address any where in the world. For example, a customer had two blade servers side by side in the same rack in Akron Ohio. We defined one IP address to be Salt Lake City Utah, and the other to be in Lexington Kentucky to achieve nicely balanced traffic patterns for all of North America. This demonstrates just one of the many flexibilities of TZO’s Geographic Load Balancing capabilities.

Virtual Traffic Manager

Drag and Drop Server locations

Virtual Traffic Manager

The new Virtual Traffic Manger (VTM) provides a Global Server View and allows for an immediate visual representation showing the exact location of your servers and their status. Based on Google Maps, zoom in and zoom out capabilities make for simple management of your environment. Whether you’re using physical or virtual locations, VTM allows for drag and drop server placement. Lat-Lon definitions are automatically changed and immediate traffic manipulation can be seen via the Global Traffic View reporting tools.

Detailed Reporting

In the “Reports” section of the control panel there are many options for looking at the near real time view of traffic distribution. Other reports include DNS  history by hour day or month.

Global Traffic View

Degraded Server Action

TZO-HA has the ability to detect a server in a degraded state. Our monitoring function can also calculate round trip time and time of execution for the monitor agent. A base line is established, whereby if a monitoring process for a given server exceeds a preconfigured number a server can be defined as in a degraded state. TZO-HA can notify on this event as well as apply a preconfigured percentage number to reduce the amount of traffic being sent to the degraded server while still allowing it to participate in the Load Balancing scheme.

Multi-Point Monitoring

TZO-HA provides for multiple monitoring agents deployed in different geographical locations. This eliminates false positive notifications. Our default is a minimum of 2 monitoring points for any one IP or device that we are monitoring. Monitoring is quite flexible and can be done in a variety of methods. Standard port and protocol communication from simple ICMP ping, SMTP, POP3, Telnet, FTP, HTTP, HTTPS, text matching and SIP as well as script execution with expected return strings can be configured.

Geo Load Balancing Product Brochure (PDF)

Download the TZO-HA Geo Load Balancing Product Brochure (PDF)