DNSSEC

When an application (such as a web browser) tries to find the IP address of a domain name, it doesn't necessarily follow all of the steps outlined in the Theory section above. We will first look at the concept of caching, then outline the operation of DNS in "the real world". Domain Name System - Caching and time to live. Because of the huge volume of requests generated by a system like the DNS, the designers wished to provide a mechanism to reduce the load on individual DNS servers. The mechanism d ...

See also:

Domain Name System, Domain Name System - A brief history of the DNS, Domain Name System - How the DNS works in theory, Domain Name System - Understanding the parts of a domain name, Domain Name System - An example of theoretical DNS recursion, Domain Name System - Understanding domain registration and glue records, Domain Name System - DNS in practice, Domain Name System - Caching and time to live, Domain Name System - Caching time, Domain Name System - DNS in the real world, Domain Name System - Other DNS applications, Domain Name System - Standards, Domain Name System - Types of DNS records, Domain Name System - Internationalized domain names, Domain Name System - DNS software, Domain Name System - Legal users of domains, Domain Name System - Registrant, Domain Name System - Administrative contact, Domain Name System - Technical contact, Domain Name System - Billing contact, Domain Name System - Name servers, Domain Name System - Politics, Domain Name System - Truth in Domain Names Act

Read more here: » Domain Name System: Encyclopedia II - Domain Name System - DNS in practice

When an application (such as a web browser) tries to find the IP address of a domain name, it doesn't necessarily follow all of the steps outlined in the Theory section above. We will first look at the concept of caching, then outline the operation of DNS in "the real world". Domain Name System - Caching and time to live. Because of the huge volume of requests generated by a system like the DNS, the designers wished to provide a mechanism to reduce the load on individual DNS servers. The mechanism d ...

See also:

Domain Name System, Domain Name System - A brief history of the DNS, Domain Name System - How the DNS works in theory, Domain Name System - Actors, Domain Name System - Understanding the parts of a domain name, Domain Name System - An example of theoretical DNS recursion, Domain Name System - Understanding domain registration and glue records, Domain Name System - DNS in practice, Domain Name System - Caching and time to live, Domain Name System - Caching time, Domain Name System - DNS in the real world, Domain Name System - Other DNS applications, Domain Name System - Standards, Domain Name System - Types of DNS records, Domain Name System - Internationalized domain names, Domain Name System - DNS software, Domain Name System - Legal users of domains, Domain Name System - Registrant, Domain Name System - Administrative contact, Domain Name System - Technical contact, Domain Name System - Billing contact, Domain Name System - Name servers, Domain Name System - Politics, Domain Name System - Truth in Domain Names Act

Read more here: » Domain Name System: Encyclopedia II - Domain Name System - DNS in practice

Main article: Internationalized domain name Domain names must use only a subset of ASCII characters—the Roman alphabet in upper and lower case, the digits 0 through 9, and the hyphen. This prevented the representation of names and words of many languages natively. ICANN has approved the Punycode-based IDNA system, which maps Unicode strings into the valid DNS character set, as a workaround to this issue. Some registries have adopted IDNA. ...

See also:

Domain Name System, Domain Name System - A brief history of the DNS, Domain Name System - How the DNS works in theory, Domain Name System - Understanding the parts of a domain name, Domain Name System - An example of theoretical DNS recursion, Domain Name System - Understanding domain registration and glue records, Domain Name System - DNS in practice, Domain Name System - Caching and time to live, Domain Name System - Caching time, Domain Name System - DNS in the real world, Domain Name System - Other DNS applications, Domain Name System - Standards, Domain Name System - Types of DNS records, Domain Name System - Internationalized domain names, Domain Name System - DNS software, Domain Name System - Legal users of domains, Domain Name System - Registrant, Domain Name System - Administrative contact, Domain Name System - Technical contact, Domain Name System - Billing contact, Domain Name System - Name servers, Domain Name System - Politics, Domain Name System - Truth in Domain Names Act

Read more here: » Domain Name System: Encyclopedia II - Domain Name System - Internationalized domain names

The practice of using a name as a more human-legible abstraction of a machine's numerical address on the network predates even TCP/IP, all the way back to the ARPAnet era. Originally, each computer on the network retrieved a file called HOSTS.TXT from SRI (now SRI International) which mapped an address (eg. 192.0.34.166) to a name (eg. www.example.com.) The Hosts file still exists on most modern operating systems either by default or through configuration and allows users to specify an IP Address to use for a hostname without checking ...

See also:

Domain Name System, Domain Name System - A brief history of the DNS, Domain Name System - How the DNS works in theory, Domain Name System - Actors, Domain Name System - Understanding the parts of a domain name, Domain Name System - An example of theoretical DNS recursion, Domain Name System - Understanding domain registration and glue records, Domain Name System - DNS in practice, Domain Name System - Caching and time to live, Domain Name System - Caching time, Domain Name System - DNS in the real world, Domain Name System - Other DNS applications, Domain Name System - Standards, Domain Name System - Types of DNS records, Domain Name System - Internationalized domain names, Domain Name System - DNS software, Domain Name System - Legal users of domains, Domain Name System - Registrant, Domain Name System - Administrative contact, Domain Name System - Technical contact, Domain Name System - Billing contact, Domain Name System - Name servers, Domain Name System - Politics, Domain Name System - Truth in Domain Names Act

Read more here: » Domain Name System: Encyclopedia II - Domain Name System - A brief history of the DNS

Domain Name System - Registrant. No one in the world really "owns" a domain name except the Network Information Centre (NIC), or domain name registry. Most of the NICs in the world receive an annual fee from a legal user in order for the legal user to utilise the domain name (i.e. a sort of a leasing agreement exists, subject to the registry's terms and conditions). Depending on the various naming convention of the registries, legal users b ...

See also:

Domain Name System, Domain Name System - A brief history of the DNS, Domain Name System - How the DNS works in theory, Domain Name System - Understanding the parts of a domain name, Domain Name System - An example of theoretical DNS recursion, Domain Name System - Understanding domain registration and glue records, Domain Name System - DNS in practice, Domain Name System - Caching and time to live, Domain Name System - Caching time, Domain Name System - DNS in the real world, Domain Name System - Other DNS applications, Domain Name System - Standards, Domain Name System - Types of DNS records, Domain Name System - Internationalized domain names, Domain Name System - DNS software, Domain Name System - Legal users of domains, Domain Name System - Registrant, Domain Name System - Administrative contact, Domain Name System - Technical contact, Domain Name System - Billing contact, Domain Name System - Name servers, Domain Name System - Politics, Domain Name System - Truth in Domain Names Act

Read more here: » Domain Name System: Encyclopedia II - Domain Name System - Legal users of domains

Many investigators have voiced criticism of the methods used currently to control ownership of domains. Most commonly, critics claim abuse by monopolies or near-monopolies, such as VeriSign, Inc., and problems with assignment of top-level domains. The international body ICANN (the Internet Corporation for Assigned Names and Numbers) oversees the domain name industry. Domain ...

See also:

Domain Name System, Domain Name System - A brief history of the DNS, Domain Name System - How the DNS works in theory, Domain Name System - Understanding the parts of a domain name, Domain Name System - An example of theoretical DNS recursion, Domain Name System - Understanding domain registration and glue records, Domain Name System - DNS in practice, Domain Name System - Caching and time to live, Domain Name System - Caching time, Domain Name System - DNS in the real world, Domain Name System - Other DNS applications, Domain Name System - Standards, Domain Name System - Types of DNS records, Domain Name System - Internationalized domain names, Domain Name System - DNS software, Domain Name System - Legal users of domains, Domain Name System - Registrant, Domain Name System - Administrative contact, Domain Name System - Technical contact, Domain Name System - Billing contact, Domain Name System - Name servers, Domain Name System - Politics, Domain Name System - Truth in Domain Names Act

Read more here: » Domain Name System: Encyclopedia II - Domain Name System - Politics

BIND (Berkeley Internet Name Domain, previously: Berkeley Internet Name Daemon) is the most commonly used DNS server on the Internet, especially on Unix-like systems, where it is a de facto standard. Supported by Internet Systems Consortium, it was originally created by Paul Vixie in 1988 while working for DEC. A new version of BIND (BIND 9) was written from scratch in part to address the architectural difficulties with auditing the earlier BIND code bases, and also to support DNSSEC (DNS Security Extension ...

Including:

• BIND - Criticisms

Read more here: » BIND: Encyclopedia - BIND

Various flavors of DNS software implement the DNS, including: BIND (Berkeley Internet Name Daemon) – full featured, most popular, de facto Internet standard djbdns (Daniel J. Bernstein's DNS) – composed of several small-footprint components DNSone - (Infoblox) MaraDNS - small-footprint IPControl (International Network Services) VitalQIP (Lucent Technologies) Adonis DNS Management Appliance (BlueCat Networks Inc) NSD (Name Server Daemon) – small footprint, UDP o ...

See also:

Domain Name System, Domain Name System - A brief history of the DNS, Domain Name System - How the DNS works in theory, Domain Name System - Understanding the parts of a domain name, Domain Name System - An example of theoretical DNS recursion, Domain Name System - Understanding domain registration and glue records, Domain Name System - DNS in practice, Domain Name System - Caching and time to live, Domain Name System - Caching time, Domain Name System - DNS in the real world, Domain Name System - Other DNS applications, Domain Name System - Standards, Domain Name System - Types of DNS records, Domain Name System - Internationalized domain names, Domain Name System - DNS software, Domain Name System - Legal users of domains, Domain Name System - Registrant, Domain Name System - Administrative contact, Domain Name System - Technical contact, Domain Name System - Billing contact, Domain Name System - Name servers, Domain Name System - Politics, Domain Name System - Truth in Domain Names Act

Read more here: » Domain Name System: Encyclopedia II - Domain Name System - DNS software

The domain name space is a tree of domain names. Each node or leaf in the tree is associated with resource records, which hold the information associated with the domain name. The tree is divided into zones. A zone is a collection of connected nodes that are authoritatively served by an authoritative DNS nameserver. (Note that a single nameserver can host several zones.) When a system administrator wants to let another administrator control a part of the domain name space within his or her zone of authority, he or ...

See also:

Domain Name System, Domain Name System - A brief history of the DNS, Domain Name System - How the DNS works in theory, Domain Name System - Understanding the parts of a domain name, Domain Name System - An example of theoretical DNS recursion, Domain Name System - Understanding domain registration and glue records, Domain Name System - DNS in practice, Domain Name System - Caching and time to live, Domain Name System - Caching time, Domain Name System - DNS in the real world, Domain Name System - Other DNS applications, Domain Name System - Standards, Domain Name System - Types of DNS records, Domain Name System - Internationalized domain names, Domain Name System - DNS software, Domain Name System - Legal users of domains, Domain Name System - Registrant, Domain Name System - Administrative contact, Domain Name System - Technical contact, Domain Name System - Billing contact, Domain Name System - Name servers, Domain Name System - Politics, Domain Name System - Truth in Domain Names Act

Read more here: » Domain Name System: Encyclopedia II - Domain Name System - How the DNS works in theory

Important categories of data stored in the DNS include the following: An A record or address record maps a hostname to a 32-bit IPv4 address. An AAAA record or IPv6 address record maps a hostname to a 128-bit IPv6 address. A CNAME record or canonical name record makes one domain name an alias of another. The aliased domain gets all the subdomains and DNS records of the original. An MX record or mail exchange record maps a domain name to a list of ...

See also:

Domain Name System, Domain Name System - A brief history of the DNS, Domain Name System - How the DNS works in theory, Domain Name System - Understanding the parts of a domain name, Domain Name System - An example of theoretical DNS recursion, Domain Name System - Understanding domain registration and glue records, Domain Name System - DNS in practice, Domain Name System - Caching and time to live, Domain Name System - Caching time, Domain Name System - DNS in the real world, Domain Name System - Other DNS applications, Domain Name System - Standards, Domain Name System - Types of DNS records, Domain Name System - Internationalized domain names, Domain Name System - DNS software, Domain Name System - Legal users of domains, Domain Name System - Registrant, Domain Name System - Administrative contact, Domain Name System - Technical contact, Domain Name System - Billing contact, Domain Name System - Name servers, Domain Name System - Politics, Domain Name System - Truth in Domain Names Act

Read more here: » Domain Name System: Encyclopedia II - Domain Name System - Types of DNS records

Important categories of data stored in the DNS include the following: An A record or address record maps a hostname to a 32-bit IPv4 address. An AAAA record or IPv6 address record maps a hostname to a 128-bit IPv6 address. A CNAME record or canonical name record makes one domain name an alias of another. The aliased domain gets all the subdomains and DNS records of the original. An MX record or mail exchange record maps a domain name to a list of ...

See also:

Domain Name System, Domain Name System - A brief history of the DNS, Domain Name System - How the DNS works in theory, Domain Name System - Actors, Domain Name System - Understanding the parts of a domain name, Domain Name System - An example of theoretical DNS recursion, Domain Name System - Understanding domain registration and glue records, Domain Name System - DNS in practice, Domain Name System - Caching and time to live, Domain Name System - Caching time, Domain Name System - DNS in the real world, Domain Name System - Other DNS applications, Domain Name System - Standards, Domain Name System - Types of DNS records, Domain Name System - Internationalized domain names, Domain Name System - DNS software, Domain Name System - Legal users of domains, Domain Name System - Registrant, Domain Name System - Administrative contact, Domain Name System - Technical contact, Domain Name System - Billing contact, Domain Name System - Name servers, Domain Name System - Politics, Domain Name System - Truth in Domain Names Act

Read more here: » Domain Name System: Encyclopedia II - Domain Name System - Types of DNS records

The practice of using a name as a more human-legible abstraction of a machine's numerical address on the network predates even TCP/IP, all the way back to the ARPAnet era. Originally, each computer on the network retrieved a file called HOSTS.TXT from SRI (now SRI International) which mapped an address (eg. 192.0.34.166) to a name (eg. www.example.com.) The Hosts file still exists on most modern operating systems either by default or through configuration and allows users to specify an IP Address to use for a hostname without checking ...

See also:

Domain Name System, Domain Name System - A brief history of the DNS, Domain Name System - How the DNS works in theory, Domain Name System - Understanding the parts of a domain name, Domain Name System - An example of theoretical DNS recursion, Domain Name System - Understanding domain registration and glue records, Domain Name System - DNS in practice, Domain Name System - Caching and time to live, Domain Name System - Caching time, Domain Name System - DNS in the real world, Domain Name System - Other DNS applications, Domain Name System - Standards, Domain Name System - Types of DNS records, Domain Name System - Internationalized domain names, Domain Name System - DNS software, Domain Name System - Legal users of domains, Domain Name System - Registrant, Domain Name System - Administrative contact, Domain Name System - Technical contact, Domain Name System - Billing contact, Domain Name System - Name servers, Domain Name System - Politics, Domain Name System - Truth in Domain Names Act

Read more here: » Domain Name System: Encyclopedia II - Domain Name System - A brief history of the DNS

Main article: Internationalized domain name Domain names must use only a subset of ASCII characters—the Roman alphabet in upper and lower case, the digits 0 through 9, and the hyphen. This prevented the representation of names and words of many languages natively. ICANN has approved the Punycode-based IDNA system, which maps Unicode strings into the valid DNS character set, as a workaround to this issue. Some registries have adopted IDNA. ...

See also:

Domain Name System, Domain Name System - A brief history of the DNS, Domain Name System - How the DNS works in theory, Domain Name System - Actors, Domain Name System - Understanding the parts of a domain name, Domain Name System - An example of theoretical DNS recursion, Domain Name System - Understanding domain registration and glue records, Domain Name System - DNS in practice, Domain Name System - Caching and time to live, Domain Name System - Caching time, Domain Name System - DNS in the real world, Domain Name System - Other DNS applications, Domain Name System - Standards, Domain Name System - Types of DNS records, Domain Name System - Internationalized domain names, Domain Name System - DNS software, Domain Name System - Legal users of domains, Domain Name System - Registrant, Domain Name System - Administrative contact, Domain Name System - Technical contact, Domain Name System - Billing contact, Domain Name System - Name servers, Domain Name System - Politics, Domain Name System - Truth in Domain Names Act

Read more here: » Domain Name System: Encyclopedia II - Domain Name System - Internationalized domain names

Domain Name System - Actors. The domain name space is a tree of domain names. Each node or leaf in the tree is associated with resource records, which hold the information associated with the domain name. The tree is divided into zones. A zone is a collection of connected nodes that are authoritatively served by an authoritative DNS nameserver. (Note that a single nameserver can host several zones.) When a system administrator wants to let another administrator control a part of the do ...

See also:

Domain Name System, Domain Name System - A brief history of the DNS, Domain Name System - How the DNS works in theory, Domain Name System - Actors, Domain Name System - Understanding the parts of a domain name, Domain Name System - An example of theoretical DNS recursion, Domain Name System - Understanding domain registration and glue records, Domain Name System - DNS in practice, Domain Name System - Caching and time to live, Domain Name System - Caching time, Domain Name System - DNS in the real world, Domain Name System - Other DNS applications, Domain Name System - Standards, Domain Name System - Types of DNS records, Domain Name System - Internationalized domain names, Domain Name System - DNS software, Domain Name System - Legal users of domains, Domain Name System - Registrant, Domain Name System - Administrative contact, Domain Name System - Technical contact, Domain Name System - Billing contact, Domain Name System - Name servers, Domain Name System - Politics, Domain Name System - Truth in Domain Names Act

Read more here: » Domain Name System: Encyclopedia II - Domain Name System - How the DNS works in theory

Many investigators have voiced criticism of the methods used currently to control ownership of domains. Most commonly, critics claim abuse by monopolies or near-monopolies, such as VeriSign, Inc., and problems with assignment of top-level domains. The international body ICANN (the Internet Corporation for Assigned Names and Numbers) oversees the domain name industry. Domain ...

See also:

Domain Name System, Domain Name System - A brief history of the DNS, Domain Name System - How the DNS works in theory, Domain Name System - Actors, Domain Name System - Understanding the parts of a domain name, Domain Name System - An example of theoretical DNS recursion, Domain Name System - Understanding domain registration and glue records, Domain Name System - DNS in practice, Domain Name System - Caching and time to live, Domain Name System - Caching time, Domain Name System - DNS in the real world, Domain Name System - Other DNS applications, Domain Name System - Standards, Domain Name System - Types of DNS records, Domain Name System - Internationalized domain names, Domain Name System - DNS software, Domain Name System - Legal users of domains, Domain Name System - Registrant, Domain Name System - Administrative contact, Domain Name System - Technical contact, Domain Name System - Billing contact, Domain Name System - Name servers, Domain Name System - Politics, Domain Name System - Truth in Domain Names Act

Read more here: » Domain Name System: Encyclopedia II - Domain Name System - Politics

Domain Name System - Registrant. No one in the world really "owns" a domain name except the Network Information Centre (NIC), or domain name registry. Most of the NICs in the world receive an annual fee from a legal user in order for the legal user to utilise the domain name (i.e. a sort of a leasing agreement exists, subject to the registry's terms and conditions). Depending on the various naming convention of the registries, legal users b ...

See also:

Domain Name System, Domain Name System - A brief history of the DNS, Domain Name System - How the DNS works in theory, Domain Name System - Actors, Domain Name System - Understanding the parts of a domain name, Domain Name System - An example of theoretical DNS recursion, Domain Name System - Understanding domain registration and glue records, Domain Name System - DNS in practice, Domain Name System - Caching and time to live, Domain Name System - Caching time, Domain Name System - DNS in the real world, Domain Name System - Other DNS applications, Domain Name System - Standards, Domain Name System - Types of DNS records, Domain Name System - Internationalized domain names, Domain Name System - DNS software, Domain Name System - Legal users of domains, Domain Name System - Registrant, Domain Name System - Administrative contact, Domain Name System - Technical contact, Domain Name System - Billing contact, Domain Name System - Name servers, Domain Name System - Politics, Domain Name System - Truth in Domain Names Act

Read more here: » Domain Name System: Encyclopedia II - Domain Name System - Legal users of domains

Various flavors of DNS software implement the DNS, including: BIND (Berkeley Internet Name Daemon) – full featured, most popular, de facto Internet standard djbdns (Daniel J. Bernstein's DNS) – composed of several small-footprint components MaraDNS – UDP only IPControl (International Network Services) VitalQIP (Lucent Technologies) Adonis DNS Management Appliance (BlueCat Networks Inc) NSD (Name Server Daemon) – small footprint, UDP only, authoritative only P ...

See also:

Domain Name System, Domain Name System - A brief history of the DNS, Domain Name System - How the DNS works in theory, Domain Name System - Actors, Domain Name System - Understanding the parts of a domain name, Domain Name System - An example of theoretical DNS recursion, Domain Name System - Understanding domain registration and glue records, Domain Name System - DNS in practice, Domain Name System - Caching and time to live, Domain Name System - Caching time, Domain Name System - DNS in the real world, Domain Name System - Other DNS applications, Domain Name System - Standards, Domain Name System - Types of DNS records, Domain Name System - Internationalized domain names, Domain Name System - DNS software, Domain Name System - Legal users of domains, Domain Name System - Registrant, Domain Name System - Administrative contact, Domain Name System - Technical contact, Domain Name System - Billing contact, Domain Name System - Name servers, Domain Name System - Politics, Domain Name System - Truth in Domain Names Act

Read more here: » Domain Name System: Encyclopedia II - Domain Name System - DNS software

To accomplish the attacks, the attacker must force the target DNS server to make a request for a domain controlled by one of the attacker's nameservers. DNS cache poisoning - Redirect the target domain's nameserver. The first variant of DNS cache poisoning involves redirecting the nameserver of the attacker's domain to the nameserver of the target domain, then assigning that nameserver an IP address specified by the attacker. DNS server's request: what are the address records for subdomain.example.com? subdomain. ...

See also:

DNS cache poisoning, DNS cache poisoning - Details, DNS cache poisoning - Variants, DNS cache poisoning - Redirect the target domain's nameserver, DNS cache poisoning - Redirect the NS record of the target domain, DNS cache poisoning - Responding before the real nameserver, DNS cache poisoning - Prevention and mitigation

Read more here: » DNS cache poisoning: Encyclopedia II - DNS cache poisoning - Variants

IPsec - Authentication Header. Authentication Header (AH) is intended to guarantee connectionless integrity and data origin authentication of IP datagrams. Further, it can optionally protect against replay attacks by using the sliding window technique and discarding old packets. AH tries to protect all fields of an IP datagram. Only fields changeable during transfer of an IP packet are excluded. An AH packet dia ...

See also:

IPsec, IPsec - Current status as a standard, IPsec - Design intent, IPsec - IPsec compared to other Internet security protocols, IPsec - Technical details, IPsec - Authentication Header, IPsec - Encapsulated Security Payload ESP, IPsec - Implementations, IPsec - Overview of IPsec-related RFCs

Read more here: » IPsec: Encyclopedia II - IPsec - Technical details

Many cache poisoning attacks can be simply prevented by DNS servers being less trusting of the information passed to them by other DNS servers, and ignoring any DNS records passed back which are not directly relevant to the query. For example, recent versions of BIND now contain code that performs these checks. As stated above, source port randomization for DNS requests, combined with the use of cryptographically-secure random numbers for selecting both the source port and the 16-bit nonce, c ...

See also:

DNS cache poisoning, DNS cache poisoning - Details, DNS cache poisoning - Variants, DNS cache poisoning - Redirect the target domain's nameserver, DNS cache poisoning - Redirect the NS record of the target domain, DNS cache poisoning - Responding before the real nameserver, DNS cache poisoning - Prevention and mitigation

Read more here: » DNS cache poisoning: Encyclopedia II - DNS cache poisoning - Prevention and mitigation