Glossary

95th Percentile

95th Percentile is a method of measuring bandwidth usage. Samples of your actual bandwidth usage are taken every five minutes from your VLAN port on the switch or T-1 Channel, utilizing MRTG Bandwidth Reporting. The program then averages the totals and posts the result as a five-minute usage point on your report. Over the month, we will continue to plot the five-minute averages, which total about 8,640 points plotted on the graph.

We then take the top five percent of your usage (432 points, or 36 hours) and throw it out!

Your usage is determined based upon the highest remaining usage plotted. This method of billing provides you with a number of advantages. Any usage bursts that are untypical of your bandwidth requirements are not charged to you, and this equates to receiving approximately your highest 36 hours of bandwidth usage each month for free.

Note that most of our customers are billed based on Bandwidth (see below) not 95th percentile.

A

Air Conditioning (AC)

Controlling the temperature, relative humidity, air cleanliness and air motion in a space to meet the requirements of the equipment.

Alternating Current (AC)

An electrical current where the polarity of the current alternated between plus and minus 60 times a second, as opposed to direct current (DC) where the polarity of the current stays constant.

Automatic Transfer Switch (ATS)

A high availability switch which provides redundant power to connected equipment. If the primary AC power becomes unavailable due to any reason, the ATS will automatically begin sourcing power from a secondary AC line. The transfer time from one line to another is seamless to the connected equipment.

Also known as a Redundant Switch.

B

Backbone

The part of a network to which other networks connect. Allows data and voice to travel from one network to another. Typically includes the entire network infrastructure required to provide connectivity between all major points.
In telephone networks includes tandem switches and the transmission facilities used to interconnect them.
In a router-based data network includes the routers and the private lines or virtual circuits used to interconnect them.

Bandwidth

How much data can flow on a given transmission path within a given amount of time. Historically, bandwidth referred to the width of the range of frequencies on which electronic signals are carried on a given transmission medium. We are able to provide bandwidth solutions from simple e-mail messages to larger video content.

Bits, Bytes and more

b Bit A single binary digit.
B Byte The amount of storage generally used to store one character of information (usually 8 bits).
Kb Kilobits Thousands of bits Kb/s= Kilobits per second
KB Kilobytes Thousands of bytes
Mb Megabits Millions of bits
MB Megabytes Millions of bytes
Gb Gigabits Thousands of Megabits
GB Gigabytes Thousands of Megabytes GB/month= Gigabytes per month

To convert from Kb per second to GB per month: GB/month = Kb/s ÷ 3.1833

Convert from GB per month to kb per second: Kb/s = GB/month x 3.1833

Border Gateway Protocol (BGP)

The core routing protocol of the Internet. It works by maintaining a table of IP networks or 'prefixes' which designate network reachability between autonomous systems (AS).

Browser

An application that retrieves WWW documents specified by URLs from an HTTP server, and displays the retrieved documents according to the Hypertext Markup Language (HTML).

C

Circuit Switch

A method widely employed by telco's to allow for a temporary dedicated path of constant bandwidth between two endpoints over a wide area.

Circuit Switched Networks

A public network dedicated to data transport which uses circuit switching techniques. Distinguished from PSTN and ISDN in that CSPDN is strictly a data network.

Circuit Switching Technology

A method widely employed by telco's to allow for a temporary dedicated path of constant bandwidth between two end points over a wide area. Users normally pay for a circuit-switched connection on a usage-sensitive basis (x cents/minute).

Co-Location

A service in which a company can have their servers housed inside the computer room of a facility directly connected to the Internet. Co-Location offers the ability to create an international business presence. Our infrastructure features diverse, redundant connectivity directly to other major Internet carriers and regional traffic exchanges.

Cookies

A data structure sent by web servers to client browsers used for retaining information about the client. The client's browser accepts a file, or cookie, from the web server. The client stores the cookie for a length of time determined by the configuration settings of the client browser.

D

Dark Fiber

Dark fiber or unlit fiber is the name given to fiber optic cables which have yet to be used. They are hence not yet connected to any device.

Data Center

A data center is a facility used for housing a large amount of electronic equipment, typically computers and communications equipment.

Denial of Service (DoS) attack

An attack on a computer system or network that causes a loss of service to users, typically loss of network connectivity and services by consuming the bandwidth of the victim network or overloading the computational resources of the victim system.

Disk Space

Disk space is the amount of space that your computer has on it, and is measured in MB (megabytes) or GB (gigabytes).

Diverse Routes

Merged routes from multiple carriers.

Domain Name Service (DNS)

The Internet service that translates server names (www.lamphost.net) to IP addresses (66.185.171.6).

Domain

A domain name is the unique name of a computer on the Internet that distinguishes it from the other systems on the network.

Every website, email account, etc, on the Internet is hosted on at least one server. Each server has a unique IP address which is nothing but a set of numbers, such as "63.215.241.202." To access a particular Internet service, one can specify its IP address in an appropriate application, such as an FTP client; however because it is difficult to remember numbers, an IP address can be associated with a fully qualified host name (a domain name), such as www.lamphost.net

F

Facility

A general term for the transmission media and equipment in communications networks; i.e., the "pipes" that carry information signals. Facilities include the physical copper pairs in a cable, carrier systems, coaxial cables, fiber optic cables, and radio and satellite systems.

Firewall

A security system designed to restrict access to computers on a Local Area Network (LAN) from the outside world, which usually means the Internet.

G

Gateway

This is a device that passes data between two different systems on a network. This includes supporting voice communication between terminals on a packet, e.g., Internet Protocol (IP) network and terminals on a circuit (e.g., Public Switched Telephone Network (PSTN).

Gigabit Ethernet (GIG-E)

The newest version of Ethernet, which supports data transfer rates of one gigabit (1,000 megabits) per second.

H

Host

Any device that is accessible on a network.

I

Internet Control Message Protocol (ICMP)

The Internet Control Message Protocol (ICMP) is part of the Internet protocol suite. ICMP messages are typically generated in response to errors in IP datagrams or for diagnostic or routing purposes.

Internet Service Provider (ISP)

A company that provides Internet access to the public or to other organizations. Most offer a full set of Internet services and provide access at either hourly rates or for a flat monthly fee.

Internet Protocol (IP)

Internet Protocol is one layer of a set of protocols which devices on the Internet use to communicate with each other. It defines how packets of data get from their source to their destination.

Internet Protocal address (IP address)

An IP address is a unique number, akin to a telephone number or street address, used by computers to refer to each other when sending information over the Internet.

L

Latency

The time interval between the instant a device makes a request for data and the instant at which the response is started.

Legacy System

A system (and the associated programs, processes, and procedures already in place) currently deployed and in use within an organization. Considered in reference to new components, or when migrating to a new system. For example, when upgrading software within an organization, the legacy applications and procedures must be considered.

Link

A Physical Layer communication path between adjacent network nodes.

Local Exchange Carrier (LEC)

A company in your town who offers you "dial tone" service. The main types of LECs are ILECs (Independent Local Exchange Carriers) and CLECs (Competitive Local Exchange Carriers).

Letter of Agency (LOA)

A letter allowing a person or business to act on behalf of another.

Local Loop

The connection between the central office and the customer's premises. Also referred to as the "last mile."

M

Mail Spooling

Using a back-up mail server to store your mail while your mail server is unavailable.

Multi-homed

Running two different connections to different ISPs for redundancy purposes, using the BGP4 protocol.

Multi-protocol Label Switching (MPLS)

A data-carrying mechanism, operating at a layer below protocols such as IP. It was designed to provide a unified data-carrying service for both circuit-based clients and packet-switching clients which provide a datagram service model. It can be used to carry many different kinds of traffic, including both voice telephone traffic and IP packets.

Multi Router Traffic Grapher (MRTG)

A tool used to monitor the traffic load on network links. MRTG generates HTML pages containing graphics which provide a LIVE visual representation of this traffic.

Mail Exchange Record (MX Record)

A record in a domain name database that identifies the mail server responsible for handling emails for that domain.

N

Network Operations Center (NOC)

A centralized location and its staff that is responsible for the operational aspects of running a production network. These tasks include monitoring and control, troubleshooting, and user assistance.

Node
A point of connection into a network.

P

Packet

bundle of data that is transmitted across a network. A packet contains the source address (where the packets come from), the destination address (where it's going), a packet identifier (so that the receiving computer can tell what sort of packet it is), and text.

Packet Switching

Sending data through a network in packets, to some remote location.

Packet Switching Network

A network designed to carry data in the form of packets.

Peer

An equal, a neighbor. The Internet is primarily a network of computers that are peers to each other, rather than a centralized system where certain devices are required for the network to function. This was because the Internet was designed to solve an important problem - to survive a nuclear war where centralized command and control is at its weakest. So long as some of the computers survived and remained connected, the surviving portion of the network would continue to operate.

Peering

Peering is the set of agreements among the companies that provide the main connections on the Internet for routing traffic among themselves. Since no one company or government is "in charge" or "owns" the Internet, the ability of any one computer on the Internet to talk to any other computer is dependent on the peering arrangements in place. These arrangements determine the path that the information will take between these two computers. These paths change continually based on the performance of the networks and the routing decisions that each carrier announces using the BGP.

Ping

A program that uses the IMCP protocol to send a message to a host's network interface to see if it exists. Useful for network troubleshooting.

Post Office Protocol 3 (POP3)

The Internet protocol used to pick up email from your mailbox at the ISP.

R

Redundancy

The duplication of critical components of a system with the intention of increasing reliability of the system.

Router

A device that connects networks together and controls the exchange of packets.

Routing

Routing provides the means of discovering paths along which information can be sent.

S

Simple Network Management Protocol (SNMP)

The Simple Network Management Protocol (SNMP) forms part of the Internet protocol suite as defined by the Internet Engineering Task Force. The protocol can support monitoring of network-attached devices for any conditions that warrant administrative attention.

Server

A computer connected to a communications network (such as the Internet) which offers a service to computers (called clients).

Service Level Agreement (SLA)

A formal written agreement made between two parties: the service provider and the service recipient. The SLA itself defines the basis of understanding between the two parties for delivery of the service itself.

Spam

Uninvited or "junk" email that advertises get rich quick schemes, websites, pornography, medications, and other generally unwanted information.

Synchronous Optical NETwork (SONET)

Synchronous Optical NETwork (SONET) ring architecture. In the event of a fiber cut, data in transmission is automatically rerouted to reach its destination via another path.

T

Transmission Control Protocol (TCP)

A connection-oriented, reliable delivery byte-stream transport layer communication protocol. The intermediate layer between the Internet Protocol below it, and an application above it.

Traceroute

A tool used to determine the specific path taken between two specific computers on the Internet. Traceroute is useful for trying to identify performance problems on the Internet.

Transfer/Month

This refers to the total amount of data transferred to and from your site each month, including web, FTP, email, and all other traffic.

Example: Every time one of your web pages is viewed by someone on the Internet, the size of that page goes towards your bandwidth usage. Below is an example of how many times a page would have to be viewed to reach 20GB of transfer.

Transmission Control Protocol/Internet protocol (TCP/IP)

The "low level" standard that makes the Internet possible - the set of rules for how different computers made by different companies can all talk to each other reliably.

Time To Live (TTL)

In general packet switching, a field that should be defined in the packet header used for switching (usually Layer 3, but possibly Layer 2), such that any unassured (or unreliable) network switching service is protected against the consequences of a route loop. Specifically in the Internet Protocol, a field processed by each IP router to prevent route loops.

U

A "U" is a Unit of Measurement for Co-Location.

Uninterruptible Power Supply (UPS)

A device that maintains a continuous supply of electric power to certain essential equipment that must not be shut down unexpectedly.

V

Virtual Host

The term Virtual Host refers to the practice of running more than one web site (such as www.example1.com and www.example2.com) on a single machine.

Virtual Private Network (VPN)

VPN software allows an Internet user to safely connect to a remote network, typically the internal network of their employer, using the public Internet. This is done by establishing a secure connection that encrypts the data being sent and received.

W

Wide Area Network (WAN)

A single network composed of multiple physical locations, interconnected by high speed data connections.