Ch. 8 Vocabulary
reverse DNS lookups
A DNS query that supplies an IP address for conversion to a corresponding domain name. Often used to double-check user identities to make sure that the domain names they present match the IP addresses in their packet headers.
inverse DNS query
A DNS query that supplies and IP address for conversion to a corresponding domain name. These are often used to double-check user identities to make sure that the domain names they present match the IP addresses in their packet headers.
nonrecursive query
A DNS query that targets one specific DNS server and terminates with whatever response may be forthcoming, whether that response is a definite answer, an error message, a null reply, or a pointer to another name server.
well-known services (WKS) record
A DNS resource record that describes the well-known IP services available from a host, such as Telnet, FTP, and so forth. Are less available to outsiders than they once were because they identify hosts that could become points of potential attack.
address (A) record
A DNS resource record that maps domain names to IPv4 addresses.
AAAA record
A DNS resource record that maps domain names to IPv6 addresses.
host information record
A DNS resource record that provides information about some specific host, as specified by its domain name.
text record
A DNS resources record that can accommodate arbitrary ASCII text data, often used to describe a DNS database segment, the hosts it contains, and so forth.
mail exchange record
A DNS resources record that's used to identify the domain name for the e-mail server that handles any particular domain or subdomain, or that's used to route e-mail traffic from one e-mail server to another while e-mail is in transit from sender to receiver.
secondary DNS server
A DNS server that contains a copy of a domain or subdomain database, along with copies of the related zone files, but that must synchronize its database and related files with whatever server is primary for that domain or subdomain.
secondary master
A DNS server that contains a copy of a domain or subdomain database, along with copies of the related zone files, but that must synchronize its database and related files with whatever server is primary for that domain or subdomain.
caching-only servers
A DNS server that does not have primary or secondary zone database responsibilities; this type of server is used only to cache already resolved domain names and addresses as related error information
caching server
A DNS server that stores valid name and address pairs already looked up, along with invalid names and addresses already detected. Any DNS server can cache data, including primary, secondary, and caching-only DNS servers.
address request
A DNS service request for an IP address that matches a domain name.
Uniform Resource Identifier
A character string that is used to identify a resource on the Internet and includes URLs and URNs.
name resolver
A client-side software component, usually part of a TCP/IP stack implementation, that's responsible for issuing DNS queries for applications and relaying whatever responses come back to those applications.
resolver
A client-side software component, usually part of a TCP/IP stack implementation, that's responsible for issuing DNS queries for applications and relaying whatever responses come back to those applications.
Nbtstat
A command-line program that returns statistics on NetBIOS, using NetBT if TCP/IP is installed on the machine from which it is run. A simple tool that displays the state of particular NetBIOS clients and NetBIOS name resolution in general.
distributed database technology
A database that's managed by multiple database servers, each of which has responsibility from some distinct portion of a global database. DNS is non pareil in its effective use of distributed database technology.
database segment
A distinct and autonomous subset of data form the DNS name and address hierarchy. Usually corresponds to a DNS database zone and is stored in a collection of interrelated zone files
DNS database segment
A distinct and autonomous subset of data from the DNS name and address hierarchy. Usually corresponds to a DNS database zone is stored in a collection of interrelated zone files.
Samba
A free software service that provides file and print sharing for Windows and that can interoperate with other operating systems, such as Linux
tree structure
A type of organized data structure, such as a taxonomy or a disk drive listing, in which the entire container acts as the root, and in which subcontainers may include either other lower-level subcontainers or instances of whatever kinds of objects may occur within a container. The domain name hierarchy adheres to an inverted tree structure because the root usually appears at the top of diagrams drawn to represent it
Nslookup
A widely implemented command-line program that supports DNS lookup and reporting capabilities. The "Ns" in this command name stands for "name server" so it's reasonable to think of this as a general-purpose name server lookup tool.
name query
An inverse DNS query that seeks to obtain a domain name for a corresponding numeric IP address.
zone data file
Any of several specific file used to capture DNS database information for static storage when a DNS server is shut down or when a secondary DNS server request synchronization with its primary DNS server's database.
zone file
Any of several specific file used to capture DNS database information for static storage when a DNS server is shut down or when a secondary DNS server request synchronization with its primary DNS server's database.
domain name hierarchy
the entire global namespace for the domain names that DNS manages on the Internet. This space includes all registered and active domain names.
delegation of authority
the principle whereby one mane server designates another name server to handle some or all of the zone files for the domain or subdomains under its purview. The DNS NS resource record provides the pointer mechanism that name servers us to delegate authority.
domain name resolution
the process whereby DNS translates a domain name into a corresponding numeric IP address.
Universal Naming Convention path
this is a naming format that points to the location of devices and resources on a network.
nonauthoritative response
Name, address, or RR information from DNS server that's not authoritative for the DNS zone being queried
root
The highest level in the domain name hierarchy, symbolized by a final period in a fully qualified domain name. provide the glue that ties together all the disparate parts of the domain name hierarchy. Provide name resolution for queries that might otherwise go unresolved.
BIND (Berkeley Internet Name Domain)
The most popular implementation of DNS server software on the Internet today. Implementations available for nearly every computing platform, including Windows Server 2003 and Windows Server 2008.
master server
The name server that's authoritative for some particular domain or subdomain and has primary custody over the DNS database segment (and related zone files) for the domain or subdomain.
primary DNS server
The name server that's authoritative for some particular domain or subdomain and has primary custody over the DNS database segment for that subdomain.
primary master
The name server that's authoritative for some particular domain or subdomain and has primary custody over the DNS database segment for that subdomain.
name resolution
The process whereby DNS translates a domain name into a corresponding numeric IP address.
stateless address auto configuration (SLAAC)
a mechanism by which an IPv6 host creates its own addresses using a combination of locally available address data and information advertised by routers.
incremental zone transfer
A type of DNS query that limits updates from a primary DNS server to one or more secondary DNS servers to only data that has changed on the primary server.
Wait Acknowledgement
A message sent by a network device such as a WINS server to acknowledge the receipt of a message from a sending node and directing the sending node to wait rather than sending more packets or expecting more data.
DNS round robin
A method of managing server congestion in which a DNS server keeps track of which IP addresses it has provided most recently for a specific translation and rotates them within the pool or list of addresses available. The DNS server can distribute the processing load, thus avoiding server congestion.
ipv6-literal.net name
A name for an IPv6 address used for services on computers that do not recognize IPv6 address syntax.
Peer Name Resolution Protocol
A name resolution protocol used for peer-to-peer network environments and that provides secure and scalable resolution services.
subdomain
A named element within a specific domain name, denoted by adding an additional name and period before the parent domain name.
zone
A portion of the domain name hierarchy that corresponds to the database segment managed by some particular name server or collection of name servers.
Link-Local Multicast Name Resolution (LLMNR)
A protocol that provides name resolution services on local networks for IPv4 and IPv6 Windows computers.
Server location (SRV) record
A record designed to provide information about available services, and used in the Windows Active Directory environment to map the name of a service to the name of a server that offers such service. AD clients and domain controller use these records to determine IP addresses for domain controllers.
authoritative response
A reply to a query from the name server that's authoritative for the zone in which the requested name or address resides.
fully qualified domain name (FQDN)
A special form of a domain name that ends with a period to indicate the root of the domain name hierarchy. Must be used in DNS A and PTR resource records.
HOSTS
A special text file that lists known domain names and corresponding IP addresses, thereby defining a static method for domain name resolution. Until DNS was implemented these files provided the sole means for name resolution on the precursor to the Internet, the ARPANET.
negative caching
A technique for storing error messages in a local cache so that repeating a query that previously produced an error message can be satisfied more quickly than if that query was forwarded to some other DNS name server.
IP spoofing
A technique whereby a programmer constructs an IP packet that presents domain name credentials that differ from the IP address in the packet header. Is often used in illicit network breakin-in attempts or to impersonate users or packet origination.
recursive query
A type of DNS query that continues until a definitive answer is forthcoming , be it a name-address translation, contents of the requested resource record, or an error message of some kind. Clients issue this to their designated name servers, which issue iterative queries to other name servers until the initial recursive request is resolved.
multihomed
Containing multiple network interfaces capable of attaching to multiple subnets.
resource record
One of a series of predefined record types in a DNS database or DNS zone file.
name resolution protocols
Procedures that govern the rules and conventions used in manually and dynamically providing for name resolution systems in a networked environment.
caching
Storing remote information locally, once obtained, so that if it is needed again, it may be accessed much more quickly. Both DNS resolvers (clients) and DNS servers cache DNS data to lower the odds that a remote query will have to be resolved.
canonical name (CNAME) record
The DNS RR used to define database aliases, primarily to make it quicker and easier to edit and manage DNS zone files.
zone transfer
The DNS mechanism in which a secondary DNS server gets its data for the zone from the master server for that zone. The secondary server checks a specific field in its SOA record and compares it to a corresponding value in the master server's database.
name server (NS) record
The DNS resource record that identifies name servers that are authoritative for some particular domain or subdomain. Often used as a mechanism to delegate authority for DNS subdomains downward in the domain name hierarchy.
Start of Authority record
The DNS resource record that's mandatory in every DNS zone file; it identifies the server or servers that are authoritative for the domain or subdomain to which the zone files or database correspond.
pointer (PTR) record
The DNS resource record that's used to inverse lookups to map numeric IP addresses to domain names.
authoritative server
The DNS server that's responsible for one or more particular zones in the DNS database environment.
