Nothing can stop u....: Setting the TL-WR843ND router as an Access point

Setting up of handful of wifi router/modem in the way it was intended(AP, modem/router, Wifi Bridge, Wifi client, WDS(Wireless Distribution System)) for, wasn't much of deal. But the various jargon and standards for 'knowledge sake' became unendingly elaborate process(Done nicely by dd-wrt). So logging what have been conceived of what have been assimilated with the block diagrammatic representation of what each stands for(image helps in visualizing than words at times) so that, these can be referred to in case the infamous forgetful syndrome.

It is useful to utilize only the Wifi Access point feature of the wireless router. Different wifi router/ router/modems have their own set of web interface to configure the wifi router as only an access point.
The wifi router who's function is to NAT route along with that other added features like DHCP, PPPoE need not be utilized or need to be underutilized by just enabling the wifi Access point.

Before setting up the wifi router as access point, know the existing network in your premises, this will make it easier to configure the router.

It looks and sounds simple for those who know the deal but for those who aren't into such stuff don't have a clue what makes in work (this is being drafted after a simple question was raised - Is there any one solution for configuring all the routers as AP - instant answer was No because of web Interface of each router are different and sometimes its not straight forward too)

But there are other non-variable factors that can be taken into consideration at the time of configuring.

Determine the LAN IP address

Determine the IP address of your LAN, mostly it will be in the range 192.168.A.B.
In GNU/Linux the info can be obtained by using ifconfig, netstat -nr or route -n or ip route show which will display the PC's ipaddress as well as the gateway.

Determine whether the router is configured as DHCP server or not

Access the web interface of the router to find out whether its DHCP server is enabled or not
if enabled
then it will allot the ip address dynamically but would recommend assigning a static ip to the connected AP
if disabled
set static ip for the host that connects to the router

Configure the new wireless router/AP by connecting it to the computer

In order to configure the router the way one wants, connect it to the computer using eth cable(It will be better to refer the routers manual)set the ip address of the router, disable the DHCP server of the router. No NAT enabled. enable the wifi beacon of the router, secure it with WEP or WPA

Place the newly configured access point whereever you want and test its working as desired

with all things working the Access point need to be connected to the LAN
the clients (wifi devices like notebook, netbook, tablet etc) should be able to acquire the ipaddress and connect to the internet,
use ping, ifconfig/ipconfig to test the connectivity and the ip address

TP-Link TL-WR843ND Specific Connect the eth cable to the LAN port(Not to the WAN Port), accessed the webinterface, disabled the DHCP, NAT features. Enabled the WiFi so that it acts only as a broadcast beacon. Gave a static IP to the router interface. Enabled the MAC in the Pass thru MAC in the captive portal.

Annex 1

Router is a device which only performs routing from one network to another.such as NAT

Access point provides wireless access to a network. It allows multiple wireless clients like laptop, netbook, tables and other wireless device to connect to the network

Annex 2

802.11b -> 2.4 GHz range, supports transfer up to 11 Mbps under ideal conditions. Transmission occurs over 20MHz of bandwidth

802.11a -> 5 GHz standard, reach 54Mbps

802.11g -> uses the same channels in 2.4GHz frequency band of 802.11b, but adopted the OFDM model of 802.11a so it also supports transfers up to 54 Mbps under ideal conditions