Background| blabs
How to Find or Validate an Email Address| www.regular-expressions.info
This memo is a status report on the parameters (i.e., numbers and keywords) used in protocols in the Internet community. Distribution of this memo is unlimited.| IETF Datatracker
Thoughts on software development| Mitendra Mahto
This Network Working Group Request for Comments documents the currently assigned values from several series of numbers used in network protocol implementations. This memo is a status report on the parameters (i.e., numbers and keywords) used in protocols in the Internet community.| IETF Datatracker
This document specifies the Internet Message Format (IMF), a syntax for text messages that are sent between computer users, within the framework of "electronic mail" messages. This specification is a revision of Request For Comments (RFC) 2822, which itself superseded Request For Comments (RFC) 822, "Standard for the Format of ARPA Internet Text Messages", updating it to reflect current practice and incorporating incremental changes that were specified in other RFCs. [STANDARDS-TRACK]| IETF Datatracker
This chapter describes how to configure different types of health checks for UDP servers in a load‑balanced upstream server group.| docs.nginx.com
Internet mail determines the address of a receiving server through the DNS, first by looking for an MX record and then by looking for an A/AAAA record as a fallback. Unfortunately, this means that the A/AAAA record is taken to be mail server address even when that address does not accept mail. The No Service MX RR, informally called "null MX", formalizes the existing mechanism by which a domain announces that it accepts no mail, without having to provide a mail server; this permits significan...| IETF Datatracker
This document describes the observed behavior of the syslog protocol. This memo provides information for the Internet community.| IETF Datatracker
This document incorporates feedback on RFC 2065 from early implementers and potential users. [STANDARDS-TRACK]| IETF Datatracker
This document defines the changes that need to be made to the Domain Name System to support hosts running IP version 6 (IPv6). [STANDARDS-TRACK]| IETF Datatracker
Let’s Encrypt protects a vast portion of the Web by providing TLS certificates to over 550 million websites—a figure that has grown by 42% in the last year alone. We currently issue over 340,000 certificates per hour. To manage this immense traffic and maintain responsiveness under high demand, our infrastructure relies on rate limiting. In 2015, we introduced our first rate limiting system, built on MariaDB. It evolved alongside our rapidly growing service but eventually revealed its lim...| letsencrypt.org
Learn about the domain name system, how it works, the types of DNS servers in use, DNS security concerns and the history of the technology.| Search Networking
The Domain Name System (DNS) has become a critical operational part of the Internet infrastructure yet it has no strong security mechanisms to assure data integrity or authentication. Extensions to the DNS are described that provide these services to security aware resolvers or applications through the use of cryptographic digital signatures. [STANDARDS-TRACK]| IETF Datatracker
This document proposes extensions to the DNS protocols to provide an incremental zone transfer (IXFR) mechanism. [STANDARDS-TRACK]| IETF Datatracker
Introduction to TLS v1.2| www.gabriel.urdhr.fr
Domain-based Message Authentication, Reporting, and Conformance (DMARC) is a scalable mechanism by which a mail-originating organization can express domain-level policies and preferences for message validation, disposition, and reporting, that a mail-receiving organization can use to improve mail handling. Originators of Internet Mail need to be able to associate reliable and authenticated domain identifiers with messages, communicate policies about messages that use those identifiers, and re...| IETF Datatracker
This memo describes a downgrade-resistant protocol for SMTP transport security between Message Transfer Agents (MTAs), based on the DNS-Based Authentication of Named Entities (DANE) TLSA DNS record. Adoption of this protocol enables an incremental transition of the Internet email backbone to one using encrypted and authenticated Transport Layer Security (TLS).| IETF Datatracker
This RFC is a snapshot of the ongoing process of the assignment of protocol parameters for the Internet protocol suite. To make the current information readily available the assignments are kept up-to- date in a set of online text files. This memo is a status report on the parameters (i.e., numbers and keywords) used in protocols in the Internet community.| IETF Datatracker
This document is a specification of the basic protocol for Internet electronic mail transport. It consolidates, updates, and clarifies several previous documents, making all or parts of most of them obsolete. It covers the SMTP extension mechanisms and best practices for the contemporary Internet, but does not provide details about particular extensions. Although SMTP was designed as a mail transport and delivery protocol, this specification also contains information that is important to its ...| IETF Datatracker
This document describes what it means to say that a Domain Name (DNS name) is reserved for special use, when reserving such a name is appropriate, and the procedure for doing so. It establishes an IANA registry for such domain names, and seeds it with entries for some of the already established special domain names.| IETF Datatracker
This document defines the changes that need to be made to the Domain Name System (DNS) to support hosts running IP version 6 (IPv6). The changes include a resource record type to store an IPv6 address, a domain to support lookups based on an IPv6 address, and updated definitions of existing query types that return Internet addresses as part of additional section processing. The extensions are designed to be compatible with existing applications and, in particular, DNS implementations themselv...| IETF Datatracker
This document describes the syslog protocol, which is used to convey event notification messages. This protocol utilizes a layered architecture, which allows the use of any number of transport protocols for transmission of syslog messages. It also provides a message format that allows vendor-specific extensions to be provided in a structured way. This document has been written with the original design goals for traditional syslog in mind. The need for a new layered specification has arisen be...| IETF Datatracker
This document specifies a syntax for text messages that are sent between computer users, within the framework of "electronic mail" messages. [STANDARDS-TRACK]| IETF Datatracker
This document describes the Dynamic Host Configuration Protocol for IPv6 (DHCPv6): an extensible mechanism for configuring nodes with network configuration parameters, IP addresses, and prefixes. Parameters can be provided statelessly, or in combination with stateful assignment of one or more IPv6 addresses and/or IPv6 prefixes. DHCPv6 can operate either in place of or in addition to stateless address autoconfiguration (SLAAC). This document updates the text from RFC 3315 (the original DHCPv6...| IETF Datatracker
This document describes a DNS RR which specifies the location of the server(s) for a specific protocol and domain. [STANDARDS-TRACK]| IETF Datatracker
This specification defines a mechanism enabling web sites to declare themselves accessible only via secure connections and/or for users to be able to direct their user agent(s) to interact with given sites only over secure connections. This overall policy is referred to as HTTP Strict Transport Security (HSTS). The policy is declared by web sites via the Strict-Transport-Security HTTP response header field and/or by other means, such as user agent configuration, for example. [STANDARDS-TRACK]| IETF Datatracker
This document specifies the behavior that is expected from the Domain Name System with regard to DNS queries for names ending with '.home.arpa.' and designates this domain as a special-use domain name. 'home.arpa.' is designated for non-unique use in residential home networks. The Home Networking Control Protocol (HNCP) is updated to use the 'home.arpa.' domain instead of '.home'.| IETF Datatracker
This document specifies a syntax for text messages that are sent between computer users, within the framework of "electronic mail" messages. [STANDARDS-TRACK]| IETF Datatracker
This document is part of a family of documents that describe the DNS Security Extensions (DNSSEC). The DNS Security Extensions are a collection of resource records and protocol modifications that provide source authentication for the DNS. This document defines the public key (DNSKEY), delegation signer (DS), resource record digital signature (RRSIG), and authenticated denial of existence (NSEC) resource records. The purpose and format of each resource record is described in detail, and an exa...| IETF Datatracker
This RFC is the revised basic definition of The Domain Name System. It obsoletes RFC-882. This memo describes the domain style names and their used for host address look up and electronic mail forwarding. It discusses the clients and servers in the domain name system and the protocol used between them.| IETF Datatracker
Investigations into musl libc DNS resolver used in Alpine containers| purplecarrot.co.uk
New talk: Learning DNS in 10 years| Julia Evans
This RFC is the revised specification of the protocol and format used in the implementation of the Domain Name System. It obsoletes RFC-883. This memo documents the details of the domain name client - server communication.| IETF Datatracker
Making a DNS query in Ruby from scratch| Julia Evans
A lot about sockets, syscalls and bits| Adam Chalmers Programming Blog
How to use Nom to parse binary protocols at the level of individual bits| Adam Chalmers Programming Blog
Just how many weird Resource Records can you stuff into a zone file? And what do these weird RRs actually return?| www.netmeister.org
The common definition of a 'valid hostname' is often reduced to a simple regular expression, but as the saying goes: 'Now you have two problems.' Because hostnames are DNS labels and those... well, it's the DNS. All bets are off.| www.netmeister.org