This glossary was written and prepared by Blair Bergum of  DNSnews.net
For additions or corrections to this glossary, please send email to glossary at dnsnews dot net

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mail.

refers to an SMTP mail server.

mail autoresponders

see autoresponders

Mail From

refers to the email headers that can be used with the Guardian Authentication process for identifying registrants of domain names so the authorized owner can make changes or modifications to their domain name.

mail server

a server that runs the mail program for sending and receiving messages. It manages the electronic email messages sent between users over a network.

MAN

Metropolitan Area Network, is a LAN that is expanded to a metropolitan area.

mapping

DNS information that points a domain name to an IP address, which is listed on a zone record.

Master NS

Master Name Server, is the authoritative server that downloads zone data to primary or secondary Name Servers.

Mbits

See Megabits.

Mbps

Megabits per second, refers to one million bits per second for data transfer. Mbps is commonly used as a measure for bandwidth, and peak bandwidth.

MBps

Megabytes per second, refers to one million bytes per second. See also Mbps. (Note the lower case letter b)

MD

Mail Destination. MD is the abbreviation used to identify the mail destination for a domain.

megabits

one million bits. Commonly used to measure bandwidth, in megabits per second, and monthly data transfer. See Mbps.

megabyte

one million bytes. 10 to the power of 6. Also written as MB. Megabytes is a unit of measure commonly used to measure disk storage capacity. Note capitalized B. Lowercase b would denote bits, that is Mb, denotes Megabits. Megabits are commonly used to measure bandwidth.

meta data

additional path information that is embedded into a URL to redirect the URL to a CDN, for example.

metrics

1) Is the art of measuring using the meter or the metric system.

2) In web hosting it is the ratio of measurement as it relates to page views, bandwidth transfer, and peak bandwidth.

MF

Mail Forward. MF is the abbreviation used to identify a mail forwarder for a domain.

midlevel

the second hierarchical layer of a hierarchical routing layer in the Internet. See hierarchical routing.

MIME

Multipurpose Internet Mail Extensions, are used to identify file types so an operating system or program knows how to handle a specific file type.

mirrored site

see mirroring.

mirroring

1) the method of running duplicated hard drives in a server that are duplicates of each other, so if one should fail the other will provide the application and data software. Mirroring uses one controller. Similar to duplexing, though duplexing uses separate hard drive controllers, one for each hard drive.

2) in web servers, mirroring is where a duplicate server is placed at another geographic location to enhance website accessibility if one server should fail. Mirroring enhances geographic accessibility due to its geographic placement. Mirroring is different than clustered shared servers where the clustered servers are connected together and in the same location. The clustered shared servers act as redundant servers should one fail. The mirror here, refers to a copy of a website, located on another server with a separate URL to access it. This is also known as a mirrored site.

Mosaic

an early browser that was created at the University of Illinois Supercomputer Center.

MoU

Memorandum of Understanding, is what ICANN entered into with the DOC on November 25, 1998 to move the government control of the Internet over to the private sector, as it relates to the gTLD’s. The ccTLD’s are left up to each county as to how those are managed and what if any restrictions that are placed on the county code TLD’s.

move domain

the act of changing or updating the Name Servers on your registration record for your domain.

MPS

Managed Private Server, refers to a server that is rented and managed professionally, by a MSP (Managed Service Provider).

MS

Microsoft Corporation.

MSP

Managed Service Providers, provide support in the areas of Internet connectivity, server support, DNS, and web-based operating systems.

MSS

Managed Security Service, is a provider who provides security devices and software, and manages the security implementation of the web servers, edge servers, and database servers for the customer.

multi-homed routing

a system of having two or more active ISP links that are connected to a router, and the router decides which link to send the packets for each server. This is a redundant design and utilizes load balancing and failover. It is also based on efficiency and performance.

multiplexed

refers to a multiple signals being sent over the same channel in one complex signal. See also multiplexer.

multiplexer

used in networking and telecommunication, is a hardware product that is capable of sending multiple signals or streams of data at the same time in the same signal and over the same channel, and then on the receiving end able to recover and separate the signals. See also multiplexing and baseband.

multiplexing

the process of a host maintaining the concurrent connections with a client using different ports.

MX record

Mail Exchange record, contains information regarding the users domain name and the name of the users’ mail server to facilitate email exchange via the Internet, as well as a preference value that indicates the mail exchangers priority.