# US 2014/0156839 A1 · Method for determining metrics of a content delivery and global traffic management network > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0156839 A1 - Document ID: US20140156839A1 - Status: Published application - Kind: A1 - Application number: 14/175,088 - Filed: 2014-02-07 - Published: 2014-06-05 - Earliest claimed: 2000-07-19 - Assignees: Akamai Technologies, Inc. - Applicants: Akamai Technologies, Inc. - Inventors: Eric Sven-Johan Swildens; Richard David Day; Ajit K. Gupta - Web page: https://patentgrep.com/patent/US20140156839A1 ## CPC - H04L 43/0805: by checking availability - H04L 12/14: Charging, metering or billing arrangements specially adapted for data communications, e.g. authentication, authorisation and accounting [AAA] framework - H04L 41/5083: {wherein the managed service relates to web hosting} - H04L 61/4511: using domain name system [DNS] - H04L 61/4541: Directories for service discovery - H04L 67/02: based on web technology, e.g. hypertext transfer protocol [HTTP] - H04L 67/06: specially adapted for file transfer, e.g. file transfer protocol [FTP] - H04L 67/1001: for accessing one among a plurality of replicated servers - H04L 67/1008: based on parameters of servers, e.g. available memory or workload (monitoring of computer activity G06F11/30) - H04L 67/101: based on network conditions - H04L 67/1027: Persistence of sessions during load balancing - H04L 67/1038: Load balancing arrangements to avoid a single path through a load balancer - H04L 67/1095: Replication or mirroring of data, e.g. scheduling or transport for data synchronisation between network nodes - H04L 69/329: in the application layer [OSI layer 7] - H04L 41/509: {wherein the managed service relates to media content delivery, e.g. audio, video or TV} - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract A method for determining metrics of a content delivery and global traffic management network provides service metric probes that determine the service availability and metric measurements of types of services provided by a content delivery machine. Latency probes are also provided for determining the latency of various servers within a network. Service metric probes consult a configuration file containing each DNS name in its area and the set of services. Each server in the network has a metric test associated with each service supported by the server which the service metric probes periodically performs metric tests on and records the metric test results which are periodically sent to all of the DNS servers in the network. DNS servers use the test result updates to determine the best server to return for a given DNS name. The latency probe calculates the latency from its location to a client's location using the round trip time for sending a packet to the client to obtain the latency value for that client. The latency probe updates the DNS servers with the clients' latency data. The DNS server uses the latency test data updates to determine the closest server to a client. ## Claims ### Claim 1 A process for determining server performance metrics in a network, comprising: determining service availability and metric measurements of types of services provided by a content delivery server using a service metric probe resident on a server; determining latency values for various content delivery servers within a network using a latency probe resident on a server; wherein the latency probe calculates a latency value from a location of the latency probe to a client's location; and wherein, for a given DNS name, a DNS server uses updates to the latency values and updates to the service availability and metric measurements to determine a content delivery server to return. ### Claim 2 (depends on 1) The process of claim 1, wherein the set(s) of services include any of: HTTP, HTTPS, FTP, streaming media, or generic SNMP. ### Claim 3 (depends on 1) The process of claim 1, wherein the service metric probe periodically performs metric tests on content delivery servers within the service metric probe area, and wherein the service metric probe records metric results from the periodic tests. ### Claim 4 A program storage medium readable by a computer, tangibly embodying a program of instructions executable by the computer to perform method steps for determining server performance metrics in a network, comprising the steps of: determining service availability and metric measurements of types of services provided by a content delivery server using a service metric probe resident on a server; determining latency values for various content delivery servers within a network using a latency probe resident on a server; wherein the latency probe calculates a latency value from a location of the latency probe to a client's location; and wherein, for a given DNS name, a DNS server uses updates to the latency values and updates to the service availability and metric measurements to determine a content delivery server to return. ### Claim 5 (depends on 4) The program storage medium of claim 4, wherein the set(s) of services include any of: HTTP, HTTPS, FTP, streaming media, or generic SNMP. ### Claim 6 (depends on 4) The program storage medium of claim 4, wherein the service metric probe periodically performs metric tests on content delivery servers within the service metric probe area, and wherein the service metric probe records metric results from the periodic tests. ### Claim 7 An apparatus for a determining server performance metrics in a network, comprising: a service metric probe resident on a server for determining service availability and metric measurements of types of services provided by a content delivery server; a latency probe resident on a server for determining latency values for various content delivery servers within a network; wherein the latency probe calculates a latency value from a location of the latency probe to a client's location; and wherein, for a given DNS name, a DNS server uses updates to the latency values and updates to the service availability and metric measurements to determine a content delivery server to return. ### Claim 8 (depends on 7) The apparatus of claim 7, wherein the set(s) of services include any of: HTTP, HTTPS, FTP, streaming media, or generic SNMP. ### Claim 9 (depends on 7) The apparatus of claim 7, wherein the service metric probe periodically performs metric tests on content delivery servers within the service metric probe area, and wherein the service metric probe records metric results from the periodic tests.