sdtest was a client simulation tool for testing DNS subscriptions. It was written in C and while useful, was limited by the amount of code required to extend it and the lack of C programmers who would do so.
Therefore, the project was terminated in favor of a new extensible tool called nst (Name Server Test tool) written in javascript node.js. See more on this site under test for more information on nst.
Discovery daemon (discd) is an implementation of the "Discovery Proxy for Multicast DNS-Based Service Discovery" specified as an internet draft of the IETF:
It dynamically maps multicast DNS services into the unicast DNS name space. This allows remote service discovery requests to be answered when the querier is not on the same link local network as the service provider.
Traditionally, zero-conf networking (or Bonjour as Apple Computer calls it) only provides answers to queries on the local network. This works great for home and small offfice (SOHO) networks but frustrates corporate and campus users when a device they want to communicate with is on another IP subnet for network scaling reasons.
By dynamically mapping the ever changing multicast DNS (mDNS) services into the unicast DNS namespace, it's possible to remotely query services through a proxy.
discd is that proxy.
more ...nst is a new tool written in javascript node.js. It is a generic DNS name server test tool that can be used to test new DNS features in a server.
A major goal is to be able to support testing of long-lived DNS connections in addition to simple query/response tests. Long-lived connections are used for DNS Privacy connection optimization, DNS Stateful Operations such as DNS Push Notifications, and service discovery with a discovery proxy and relay.
sdtest is a client simulation tool for testing DNS subscriptions. It supports both the older Long Lived Queries (LLQ) and the new replacement DNS Push Notifications.
Since it is a work in progress, the best way to follow it is to look at the github sdtest project documentation that is being updated as the code is written.
https://github.com/pusateri/sdtest
more ...In July of 2016, I gave a talk to the IETF DNS-SD Working Group in Berlin with a status update of DNS Push Notifications.
Here are the slides:
In March of 2015, I gave a talk to the IETF DNS-SD Working Group in Dallas introducing DNS Push Notifications. This work was a joint effort between Stuart Cheshire and myself as a next generation follow on to LLQ.
Here are the slides:
In November of 2014, I gave a talk to the IETF DNS-SD Working Group in Honolulu explaining how Long Lived Queries (LLQ) work.
Here are the slides:
In June of 2014, I gave an invited talk to the Research & Education Track of NANOG 61 explaining what a Discovery Proxy was (Hybrid Proxy at the time) and how Long Lived Queries (LLQ) works. The link at the end of the slides http://hypd.info is no longer valid and should be changed to https://dnsdisco.com.
Here are the slides:
DNS Disco 