802.11a

An IEEE specification for wireless networking that operates in the 5 GHz frequency range (5.15 GHz to 5.850 GHz) with a maximum of 54 Mbps data transfer rate.  The 5 GHz frequency band is not as crowded as the 2.4 GHz band. In addition, the 802.11a has 12 non-overlapping channels, comparing to 802.11b/g's 3 non-overlapping channels.  This means the possibility to build larger non-interfering networks.  However, the 802.11a deliver shorter distance at the same output power when comparing to 802.11g.



802.11ac (also known as 11ac)

The IEEE wireless standard that was established in 2013.  Also known as 11ac.  Comparing to 802.11n, the 802.11ac increase the channel width from 40MHz to 80/160Mhz in the 5GHz spectrum.  It also has a higher order of modulation up to 256QAM.  For 11ac Wave 2, it increases the channel width to 160MHz and enables MU-MIMO(multi-user MIMO) capability.  One stream of 11ac has 433Mbps / 450Mbps data rate.  So for example, 2T2R 11ac has 2x150Mbps(11n)+2x450Mbps=1200Mbps throughput.  The 11ac is backward compatible with 11a/b/g/n.



802.3ad

802.3ad is an IEEE standard for bonding or aggregating multiple Ethernet ports into one virtual port (also known as trunking) to increase the bandwidth.



802.3af

This is the PoE (Power over Ethernet) standard by IEEE committee. 803.af uses 48V POE standard that can deliver up to a 100-meter distance over Ethernet cable.  802.3af can output a maximum of 15.4W per port



802.11an (also known as 11an)

An IEEE standard for an 802.11n standard that operates in the 5GHz frequency spectrum.  Comparing to 802.11a, the 802.11an adds MIMO(multi-in multi-out) capability.  The maximum throughput depends on the number of radio stream available.  Each stream has approximately 150Mbps data rate.  For example, a 3T3R MIMIO can reach maximum of 450Mbps.



802.3at (also known as POE+)

This is the PoE (Power over Ethernet) standard by IEEE committee.  The 802.3at deliver both data and power through Ethernet cable.  The 802.at can output a maximum of 30W per port(compare to 802.11af’s 15.4W) and is backward compatible with 802.11af.



802.11ax (also known as 11ax)

The 802.11ax is the upcoming WiFi standard which can increase the overall bandwidth up to 4X of 11ac.  The modulation rate is increased to 1024QAM(compared to 256QAM of 11ac).  The per stream data rate is up to 800Mbps.  The biggest change is the introduction of OFDMA which can maintain performance and stability in a crowded environment.  Making the 802.11ax a good solution for public WiFi.



802.11b (also know as 11b)

An international standard for wireless networking that operates in the 2.4 GHz frequency band (2.4 GHz to 2.4835 GHz) and provides a throughput up to 11 Mbps.  


802.1d STP

Spanning Tree Protocol.  It is an algorithm to prevent a network loop from forming. The STP protocol allows the network to provide a redundant link in the event of a link failure.  It is advisable to turn on this option for multi-link bridge network.


802.11d

Also known as “Global Roaming”.  802.11d is a standard for use in countries where systems using other standards in the 802.11 families are not allowed to operate.


802.11e

The IEEE QoS standard for prioritizing traffic of the VoIP and multimedia applications.  The WMM is based on a subset of the 802.11e.


802.11g (also known as 11g)

A standard provides a throughput up to 54 Mbps using OFDM technology.  It also operates in the 2.4 GHz frequency band as 802.11b.  802.11g devices are backward compatible with 802.11b devices.


802.11h

This IEEE standard defines the TPC(transmission power control) and DFS(dynamic frequency selection) required to operate WiFi devices in 5GHz for EU.


802.11i

The IEEE standard for wireless security.  802.11i standard includes TKIP, CCMP, and AES encryption to improve wireless security.  It is also known as WPA2.


802.11k

The 802.11k was an IEEE standard established in 2008 to facilitate the method of finding the information and condition about surrounding wireless network information.  It is often used together with 802.11r protocol to facilitate fast wireless roaming.  With 802.11k detecting and finding the next best AP to handover and 802.11r executes the actual handoff process.  The result is uninterrupted voice or data transmission when a wireless client moves from one location to the other.


802.11n (also known as 11n)

The IEEE 802.11 standard improves network throughput over 802.11a and 802.11g with a significant increase in the maximum data rate from 54 Mbps to 600 Mbps.  802.11n standardized the support for multiple-input-multiple-output (MIMO) and frame aggregation, and security improvements.  Unless specified, 802.11n typically operates in 2.4GHz only.  The 802.11n that operates in 5GHz is called 802.11an.


802.1Q Tag VLAN

In 802.1Q VLAN, the VLAN information is written into the Ethernet packet itself.  Each packet carries a VLAN ID(called Tag) as it traveled across the network.  Therefore, the VLAN configuration can be configured across multiple switches.  In 802.1Q spec, possible 4096 VLAN ID can be created.  Although for some devices, they can only view in frames of 256 ID at a time.



802.11r

802.11r is an IEEE standard that was published in 2008 which facilitates the method for fast roaming and handoff between wireless base stations.  This will result in seamless roaming from one Access Point to the other.  The standard is often coupled with the 802.11k standard.  For example, AP with 802.11r/k standard can provide uninterrupted voice call when a WiFi phone move from one station to the other.


802.1x

802.1x is a security standard for wired and wireless LANs.  In the 802.1x parlance, there are usually supplicants (client), authenticator (switch or AP), and an authentication server (radius server) in the network.  When a supplicants request a service, the authenticator will pass the request and wait for the authentication server to grant access and register accounting.  The 802.1x is the most widely used method of authentication by WISP.


Adhoc

A Peer-to-Peer wireless network.  An Adhoc wireless network does not use wireless AP or router as the central hub of the network.  Instead, wireless clients are connected directly to each other.  The disadvantage of an Adhoc network is the lack of wired interface to Internet connections.  It is not recommended for networking more than 2 nodes.


Access Point (AP)

The central hub of a wireless LAN network.  Access Points have one or more Ethernet ports that can connect devices (such as Internet connection) for sharing. Multi-function Access Point can also function as an Ethernet client, wireless bridge, or repeat signals from other AP.  Access Points typically have more wireless functions comparing to wireless routers.


ACK Timeout

Acknowledgement Timeout Windows.  When a packet is sent out from one wireless station to the other, it will wait for an Acknowledgement frame from the remote station.  The station will only wait for a certain amount of time, this time is called the ACK timeout.  If the ACK is NOT received within that timeout period then the packet will be re-transmitted resulting in reduced throughput.  If the ACK setting is too high then throughput will be lost due to waiting for the Ack Window to timeout on lost packets.  If the ACK setting is too low then the ACK window will have expired and the returning packet will be dropped, greatly lowering throughput.  By having the ability to adjust the ACK setting we can effectively optimize the throughput over long distance links.  This is especially true for 802.11a and 802.11g networks.  Setting the correct ACK timeout value need to consider 3 factors: distance, AP response time, and interference.  The AirMax5N provide ACK adjustment capability in form of either distance or direct input.  When you enter the distance parameter, the AirMax5N will automatically calculate the correct ACK timeout value.  



Band Steering

Band Steering is a method to distribute the wireless clients between 2.4Ghz and 5GHz.  The AP can kick the wireless clients off one frequency band and redirect them to another band.  Band Steering usually has 2 modes.  “The 5GHz first” mode will allocate most of the client to 5GHz first until it is full.  The “balanced mode” will try to evenly distribute between 5GHz and 2.4GHz  


Bandwidth Management

Bandwidth Management controls the transmission speed of a port, user, IP address, and application.  A router can use bandwidth control to limit the Internet connection speed of individual IP or Application.  It can also guarantee the speed of certain special application or privileged IP address - a crucial feature of QoS (Quality of Service) function.  The AirMax5N’s features both “Per-user Bandwidth Control” and “Total Bandwidth Control”.  “Per-user Bandwidth Control” allows the administrator to define the maximum bandwidth of each user by IP, IP Group, or MAC address.  Total Bandwidth defines the maximum bandwidth of wireless or Ethernet interface.


Bootloader

A bootloader is the under layering program that will start at the power-up before the device loads firmware.  It is similar to BIOS on a personal computer.  When a firmware crashed, you might be able to recover your device from the bootloader.


Bridge

A product that connects 2 different networks that use the same protocol.  Wireless bridges are commonly used to link network across remote buildings.  For a wireless application, there are 2 types of Bridges.  WDS Bridge can be used in Point-to-Point or Point-to-Multipoint topology.  Bridge Infrastructure works with AP mode to form a star topology.


Cable and Connector Loss

During wireless design and deployment, it is important to factor in the cable and connector loss.  Cable and connector loss will reduce the output power and receiver sensitivity of the radio at the connector end.  The longer the cable length is, the more the cable loss.  Cable loss should be subtracted from the total output power during distance calculation.  For example, if the cable and connector loss is 3dBm and the output power is 20dBm; the output power at the cable end is only 17dBm.


Captive Portal

Captive Portal is usually used for guest access or other types of access control.  For example, when a user is connected to a WiFi network with captive portal, a login page will pop-up asking user to enter username and password.  Only after the correct information is entered, the user can gain access to the Internet.


Client

Client means a network device or utility that receives service from host or server.  A client device means end user device such as wireless cards or wireless CPE.


CPE Devices

CPE stands for Customer Premises Equipment.  A CPE is a device installed on the end user's side to receive network services.  For example, on an ADSL network, the ADSL modem/router on the subscriber's home is the CPE device.  Wireless CPE means a complete Wireless (usually an AP with built-in Antenna) that receive wireless broadband access from the WISP.  The opposite of CPE is CO.


CTS

Clear To Send.  A signal sent by a device to indicate that it is ready to receive data.


DDNS

Dynamic Domain Name System.  An algorithm that allows the use of dynamic IP address for hosting Internet Server.  A DDNS service provides each user account with a domain name.  A router with DDNS capability has a built-in DDNS client that updates the IP address information to DDNS service provider whenever there is a change.  Therefore, users can build a website or other Internet servers even if they don't have fixed IP connection.


DHCP

Dynamic Hosting Configuration Protocol.  A protocol that enables a server to dynamically assign IP addresses.  When DHCP is used, whenever a computer logs onto the network, it automatically gets an IP address assigned to it by DHCP server.  A DHCP server can either be a designated PC on the network or another network device, such as a router.


DHCP Snooping

DHCP Snooping is to prevent authorized installation of DHCP server or router on the network.  An unauthorized DHCP server or router can seriously disrupt the network by providing false gateway information.  A switch equipped with DHCP Snooping can allow DHCP packet only from selected ports.


DMZ

Demilitarized Zone.  When a router opens a DMZ port to an internal network device, it opens all the TCP/UDP service ports to this particular device.  The feature is used commonly for setting up H.323 VoIP or Multi-Media servers.


DNS

A program that translates URLs to IP addresses by accessing a database maintained on a collection of Internet servers.  


Domain Name

The unique name that identifies an Internet site.  Domain Names always have 2 or more parts, separated by dots.  In www.airlive.com, the "airlive.com" is the domain name.


DoS Attack

Denial of Service.  A type of network attack that floods the network with useless traffic.  Many DoS attacks, such as the Ping of Death and Teardrop attacks, exploit limitations in the TCP/IP protocols.


EMAP

An electronic map that can display location, coverage, a status of your devices.  There are usually 2 types of E-MAP.  One is Zone Plan which displays the floor plan of the building.  The other is Google Map which displays the geographical location.


Encryption

Encoding data to prevent it from being read by unauthorized people.  The common wireless encryption schemes are WEP, WPA, and WPA2.


ESSID (SSID)

The identification name of an 802.11 wireless network.  Since the wireless network has no physical boundary liked wired Ethernet network, wireless LAN needs an identifier to distinguish one network from the other.  Wireless clients must know the SSID in order to associate with a WLAN network.  Hide SSID feature disable SSID broadcast, so users must know the correct SSID in order to join a wireless network.



ERPS

ERPS is an ITU-T standard to ensure there is no loop form and ensure fast recovery of less than 50ms when one path is broken.  The concept is similar to STP(spanning tree) except it operates at much faster speed for recovery.  ERPS will allow the ring to form and disable the path that will create loops.  But when a path is broken, it will enable another path to ensure the continued connection between 2 points.


Firewall

A system that secures a network and prevents access by unauthorized users.  Firewalls can be software, router, or gateway.  Firewalls can prevent unrestricted access to a network, as well as to restrict data from flowing out of a network.


Firmware

The program that runs inside the embedded device such as router or AP.  Many network devices are firmware upgradeable through a web interface or utility program.


FTP

File Transfer Protocol.  A standard protocol for sending files between computers over a TCP/IP network and the Internet.


Fragment Threshold

Frame Size larger than this will be divided into a smaller fragment.  If there are interferences in your area, lower this value can improve the performance.  If there are not, keep this parameter at a higher value.  The default size is 2346.  You can try 1500, 1000, or 500 when there is interference around your network.


Full Duplex

The ability of a networking device to receive and transmit data simultaneously.  In a wireless environment, this is usually done with 2 or more radios doing load balancing.


Gateway

In the global Internet network, the gateways are core routers that connect networks in different IP subnet together.  In a LAN environment with an IP sharing router, the gateway is the router.  In an office environment, gateway typically is a multi-function device that integrates NAT, firewall, bandwidth management, and other security functions.


Hotspot

A place where you can access Wi-Fi service.  The term hotspot has two meanings in wireless deployment.  One is the wireless infrastructure deployment; the other is the Internet access billing system.  In a hotspot system, a service provider typically needs an authentication and account system for billing purposes, and a wireless AP network to provide access for customers.


IGMP Snooping

Internet Group Management Protocol(IGMP) is a Layer 3 protocol to report IP multicast memberships to neighboring multicast switches and routers.  IGMP snooping is a feature that allows an Ethernet switch to "listen in" on the IGMP conversation between hosts and routers.  A switch support IGMP snooping has the possibility to avoid multicast traffic being treated as broadcast traffic; therefore, reducing the overall traffic on the network.


Infrastructure Mode

A wireless network that is built around one or more access points to provide wireless clients access to wired LAN / Internet service.  The opposite of Infrastructure mode is Adhoc mode.


IP address

IP(Internet Protocol) is a layer-3 network protocol that is the basis of all Internet communication.  An IP address is a 32-bit number that identifies each sender or receiver of information that is sent across the Internet.  An IP address has two parts: an identifier of a particular network on the Internet and an identifier of the particular device (which can be a server or a workstation) within that network.  The new IPv6 specification supports 128-bit IP address format.


IPsec

IP Security.  A set of protocols developed by the IETF to support secure exchange of packets at the IP layer.  IPsec has been deployed widely to implement Virtual Private Networks (VPNs).  IPsec supports two encryption modes: Transport and Tunnel.  Transport mode encrypts only the data of each packet but leaves the header untouched.  The more secure Tunnel mode encrypts both the header and the payload.  On the receiving side, an IPSec-compliant device decrypts each packet.


LACP (802.3ad) Trunking

The 802.3ad Link Aggregation standard defines how to combine the several Ethernet ports into one high-bandwidth port to increase the transmission speed.  It is also known as port trunking.  Both devices must set the trunking feature to work.


MAC Address

Media Access Control. MAC address provides layer-2 identification for Networking Devices.  Each Ethernet device has its own unique address.  The first 6 digits are unique for each manufacturer.  When a network device has MAC access control feature, only the devices with the approved MAC address can connect to the network.


Mbps

Megabits Per Second.  One million bits per second; a unit of measurement for data transmission


MESH

Mesh is an outdoor wireless technology that uses Spanning Tree Protocol(STP) and Wireless Distribution system to achieve self-forming, self-healing, and self-configuring outdoor network.  MESH network are able to take the shortest path to a destination that does not have to be in the line of site.


MIMO

Multi In Multi Out.  A Smart Antenna technology designed to increase the coverage and performance of a WLAN network.  In a MIMO device, 2 or more antennas are used to increase the receiver sensitivity and to focus available power at intended Rx.


MU-MIMO

Multi-user MIMO.  It is part of 11ac wave 2’s feature.  Traditionally, MIMO only works with one user at the time.  When one user is using it, the other user can’t get the benefit of MIMO.  MU-MIMO allows multiple users to have MIMO access at the same time.


NAT

Network Address Translation.  A network algorithm used by Routers to enables several PCs to share single IP address provided by the ISP.  The IP that a router gets from the ISP side is called Real IP, the IP assigned to PC under the NAT environment is called Private IP.


NMS

NMS stands for Network Management System.  A software or hardware controller is presented on the network to manage or configure other network devices such as AP or Switch.


NMS Mode

Some Edimax AP models have AP Controller mode(NMS mode) built inside.  When enabled, it can manage other access points


Node

A network connection endpoint, typically a computer or a network device.


Packet

A unit of data sent over a network.


Passphrase

Used much like a password, a passphrase simplifies the WEP encryption process by automatically generating the WEP encryption keys for the company products.


PD Alive Check (also known as Ping Watchdog)

This is a function in PoE switch that will periodically ping the device.  When a device fails to respond multiple time, the PoE switch will cut OFF then ON the power and let the device repower itself.  Most of the time, this can solve the issue.


Private Cloud

A private Cloud is usually a software that runs on cloud server service such as Amazon AWS.  Its access is restricted to the administrator.  Private Cloud does not open to the public to access.



PM 2.5

PM 2.5 is a particle that is smaller than 2.5 micron in diameter.  Particle this small can penetrate the lungs and remain in our body.  It can cause series damage to our respiratory system if it has been inhaled over a long period of time.



POE

Power over Ethernet.  A standard to deliver both power and data through one single Ethernet cable (UTP/STP).  It allows a network device to be installed far away from power source.  A POE system typically composes of 2 main component: DC Injector (Base Unit) and Splitter (Terminal Unit).  The DC injector combines the power and data, and the splitter separates the data and power back. A PoE Access Point or CPE has the splitter built-in to the device.  The IEEE 802.3af is a POE spec that uses 48 volts to deliver power up to a 100-meter distance.



Port

This word has 2 different meaning for networking.

  • The hardware connection point on a computer or networking device used for plugging in a cable or an adapter.
  • The virtual connection point through which a computer uses a specific application on a server.



PPPoE

Point-to-Point Protocol over Ethernet.  PPPoE relies on two widely accepted standards: PPP and Ethernet.  PPPoE is a specification for connecting the users on an Ethernet to the Internet through a common broadband medium, such as a single DSL line, wireless device or cable modem.  



PPTP

Point-to-Point Tunneling Protocol: A VPN protocol developed by PPTP Forum.  With PPTP, users can dial into their corporate network via the Internet.  If users require data encryption when using the Windows PPTP client, the remote VPN server must support MPPE(Microsoft Point-To-Point Encryption Protocol) encryption.  PPTP is also used by some ISPs for user authentication, particularly when pairing with legacy Alcatel / Thomson ADSL modem.



Public Cloud

Public cloud usually is a software management program that runs on cloud service such as Amazon AWS.  Compare to the private cloud which is only open to one administrator, the public cloud is open to multiple administrator accounts.  Usually, the administrator will subscribe to the public cloud service and then has his/her own access to device management.



Preamble Type

A preamble is sent with each wireless packet transmitted for transmission status.  Use the long preamble type for better compatibility.  Use the short preamble type for better performance



Rate Control

Ethernet switches' function to control the upstream and downstream speed of an individual port.  Rate Control management uses "Flow Control" to limit the speed of a port.  Therefore, the Ethernet adapter must also have the flow control enabled.  One way to force the adapter's flow control on is to set a port to half-duplex mode.



RADIUS

Remote Authentication Dial-In User Service.  An authentication and accounting system used by many Internet Service Providers(ISPs). When you dial into the ISP, you must enter your username and password.  This information is passed to a RADIUS server, which checks that the information is correct, and then authorizes access to the ISP system.  RADIUS typically uses port 1812 and port 1813 for authentication and accounting port.  Though not an official standard, the RADIUS specification is maintained by a working group of the IETF.



Receiver Sensitivity

Receiver sensitivity means how sensitive is the radio for receiving signal.  In general; the slower the transmission speed, the more sensitive the radio is.  The unit for Receiver Sensitivity is in dB; the lower the absolute value is, the higher the signal strength.  For example, -50dB is higher than -80dB.



Repeater/Extender

It is also known as a wireless extender.  The function is to extend the coverage of your wireless router or AP.  It will receive the signal from the wireless router/AP then re-broadcast it.  When some corner of your home, office, or hotel cannot receive signal, adding a wireless repeater is the simplest solution.



RJ-45

Standard connectors for Twisted Pair copper cable used in Ethernet networks.  Although they look similar to standard RJ-11 telephone connectors, RJ-45 connectors can have up to eight wires, whereas telephone connectors have only four.



Roaming

Roaming for WiFi means the process when a wireless client moves from one Access Point to the other.  It defines how the AP will handoff and transfers to another client.  The typical standard for seamless or fast roaming for WiFi devices is the 802.11r/k standard.



Router

An IP sharing router is a device that allows multiple PCs to share one single broadband connection using NAT technology.  A wireless router is a device that combines the functions of a wireless Access Point and the IP sharing router.



RSSI

Receiver Sensitivity Index.  RSSI is a value to show the Receiver Sensitivity of the remote wireless device.  In general, remote APs with the stronger signal will display higher RSSI values.  For RSSI value, the smaller the absolute value is, the stronger the signal.  For example, “-50db” has a stronger signal than “-80dB”.  For outdoor connection, signal stronger than -60dB is considered as a good connection.



RTS

Request To Send.  A packet sent when a computer has data to transmit.  The computer will wait for a CTS(Clear To Send) message before sending data.



RTS Threshold

RTS(Request to Send).  The RTS/CTS(clear to send) packet will be sent before a frame if the packet frame is larger than this value.  Lower this value can improve the performance if there are many clients in your network.  You can try 1500, 1000 or 500 when there are many clients in your AP’s network.



SKYMANAGE

This is Edimax Pro’s SMB Public cloud service in development.  Users will be able to register an account then manage their Edimax Pro APs or switches from a remote site.



SKYMANAGE PC

This is Edimax Pro’s Software NMS and Private Cloud.  It requires Windows-based PC to run.  When installed on a PC, it can manage up to 250 APs locally.  When installed on Cloud service such as Amazon AWS, it can manage all these devices remotely.



SNMP

Simple Network Management Protocol. A set of protocols for managing complex networks.  The SNMP network contains 3 key elements: managed devices, agents, and network-management systems(NMSs).  Managed devices are network devices that content SNMP agents.  SNMP agents are programs that reside SNMP capable device's firmware to provide SNMP configuration service.  The NMS typically is a PC based software such as HP OpenView that can view and manage SNMP network devices remotely.  SNMP uses private MIB of the device to learn how to write the configuration to the device.


SSH

Developed by SSH Communications Security Ltd., Secure Shell is a program to log into another computer over a network, to execute commands in a remote machine, and to move files from one machine to another.  It provides strong authentication and secure communications over insecure channels. It is a replacement for rlogin, rsh, rcp, and rdist.


SSL

Secure Sockets Layer.  It is a popular encryption scheme used by many online retail and banking sites to protect the financial integrity of transactions.  When an SSL session begins, the server sends its public key to the browser.  The browser then sends a randomly generated secret key back to the server in order to have a secret key exchange for that session.  SSL VPN is also known as Web VPN.  The HTTPS and SSH management interface use SSL for data encryption.



STP

Spanning Tree Protocol.  Spanning Tree Protocol ensure there is only one path in between 2 points.  When the path is broken, STP will enable another path to recover the connection.  This is also known as "Ring" topology.  In 2001, the IEEE introduced the 802.1w RSTP(Rapid Spanning Tree) with faster recovery time.



Subnet Mask

An address code mask that determines the size of the network.  An IP subnet is determined by performing a BIT-wise AND operation between the IP address and the subnet mask.  By changing the subnet mask, you can change the scope and size of a network.  


Subnetwork or Subnet

Found in larger networks, these smaller networks are used to simplify addressing between numerous computers.  Subnets connect to the central network through a router, hub or gateway.  Each individual wireless LAN will probably use the same subnet for all the local computers it talks to.


TCP

A layer-4 protocol used along with the IP to send data between computers over the Internet.  While IP takes care of handling the actual delivery of the data, TCP takes care of keeping track of the packets that a message is divided into for efficient routing through the Internet.  


TDMA

TDMA is a method of transmitting the data by Time Division Multiplexing.  Comparing to the Frequency Division used by WiFi standards, TDMA offers lower throughput in short distance environment.  However, for long distance and point-to-multipoint outdoor application, TDMA offers better performance and stability.


TX Output Power

Transmit Output Power.  The TX output power means the transmission output power of the radio.  Normally, the TX output power level limit for 2.4GHz 802.11b/g is 20dBm at the antenna end.  The output power limit for 5GHz 802.11a is 30dBm at the antenna end.



UDP

User Datagram Protocol. A layer-4 network protocol for transmitting data that does not require acknowledgment from the recipient of the data.


Upgrade

To replace existing software or firmware with a newer version.


Upload

To send a file to the Internet or network device.


URL

Uniform Resource Locator. The address of a file located on the Internet.


VLAN

VLAN is a virtual network which can separate one network from the other.  VLAN can be deployed in both wired and wireless network.  There are commonly 2 types of VLAN.  One is port-based VLAN which is used on Ethernet switches to separate one port group to the other.  Another type is 802.1Q tag-based VLAN.  Tag-based VLAN puts a tag on each packet with an identity which VLAN group it belongs to.  Therefore, it is possible to build a virtual network across both wired and wireless network.


VPN

Virtual Private Network.  A type of technology designed to increase the security of information transferred over the Internet.  VPN creates a private encrypted tunnel from the end user's computer, through the local wireless network, through the Internet, all the way to the corporate network.


Walled Garden

On the Internet, a walled garden refers to a browsing environment that controls the information and Web sites the user is able to access.  This is a popular method used by ISPs in order to keep the user navigating only specific areas of the Web


WAN

Wide Area Network.  A communication system of connecting PCs and other computing devices across a large local, regional, national or international geographic area.  A WAN port on the network device means the port (or wireless connection) that is connected to the Internet side of the network topology.


WEP

Wired Equivalent Privacy.  A wireless encryption protocol.  WEP is available in 40-bit (64-bit), 108-bit (128-bit) or 152-bit (Atheros proprietary) encryption modes.


Wi-Fi

Wireless Fidelity.  An interoperability certification for wireless local area network(LAN) products based on the IEEE 802.11 standards.  The governing body for Wi-Fi is called Wi-Fi Alliance (also known as WECA).


WDS

Wireless Distribution System.  WDS defines how multiple wireless Access Point or Wireless Router can connect together to form one single wireless network without using wired uplinks.  WDS associate each other with MAC address of each device.


WLAN

Wireless Local Area Network.  A type of local-area network that uses high-frequency radio waves rather than wires to communicate between nodes.  The most popular standard for WLAN is the 802.11 standards.


WMM

Wi-Fi Multimedia(WMM) is a standard to prioritize traffic for multimedia applications.  The WMM prioritizes traffic on Voice-over-IP(VoIP), audio, video, and streaming media as well as traditional IP data over the AP.


WMS

Wireless Management System.  A utility program to manage multiple wireless AP/Bridges.


WPA

Wi-Fi Protected Access.  It is an encryption standard proposed by WiFi for advance protection by utilizing a password key (TKIP) or certificate.  It is more secure than WEP encryption.  The WPA-PSK utilizes a pre-shared key for encryption/authentication.  


WPA2

Wi-Fi Protected Access 2.  WPA2 is also known as 802.11i.  It improves on the WPA security with CCMP and AES encryption.  The WPA2 is backward compatible with WPA.  WPA2-PSK utilizes a pre-shared key for encryption/authentication.