The 2.4GHz band frequency ranges from 2.4GHz-2.4835GHz and is used by 802.11a, 802.11b, 802.11g. The band is divided into 14 fixed-frequency channels, each being 20MHz wide.
The gap between adjacent channels is 5MHz wide, and these channels have many overlaps. Thus, only 3 channels can be active at the same time. You can find non-overlapping channels like 1, 6, and 11. The 2.4GHz band is very crowded as this range is also used by devices like baby monitors, cordless phones, microwave ovens, Bluetooth, etc... Not many channels are available for use. And is susceptible to more interference.
But the advantage…
IEEE standards refer to the set of layer 1 and layer 2 specifications for a WLAN.
The first version was released in 1997, and 6 different versions have been brought since then. — 1) 802.11a, 2) 802.11b, 3) 802.11g, 4) 802.11n, 5) 802.11ac, and 6) 802.11ad
Collectively these standards are known as wireless fidelity (WI-FI).
All these standards are similar in 3 aspects:
MIMO — Multiple Input Multiple Output
In wireless networks, association means wireless devices register with an AP/router to get access to the network. Association happens only in infrastructure mode, not in Ad Hoc mode.
To establish this association, a wireless device uses scanning methods to find an AP/router.
A wireless device broadcasts a probe signal to each channel in its frequency range and waits for an AP to respond. So the client initiates the search method.
WLAN is a network in which devices are communicating wirelessly with each other in a defined area.
The WLAN is ultimately connected to a wired network.
A Wireless access point or simply called an access point accepts a wireless signal from multiple devices and retransmits them to the rest of the network. At-home settings, a WAP may be capable of routing therefore may also be called a wireless router or wireless gateway. But in business settings, AP and routers are separate devices. …
WLAN has 2 architecture modes: Ad Hoc, Infrastructure
Ad Hoc mode is a decentralized type of network. Wireless devices communicate with each other directly instead of using an access point. So Ad Hoc mode is peer-to-peer. It doesn't need a complex setup. It is quick and cheap.
As more users get connected to the network this type of network shows deterioration in performance. And security is also not that. Use it only if your devices trust each other.
This mode is more common with companies and organizations. This is a centralized wireless network where devices communicate via access points and…
All devices in an IPv6 network are required to have a link-local unicast address, starting with FE80::/64. The device can generate the other 64bit half by the EUI-64 method or by generating random value.
But, before a device starts using the self-generating address, it needs to check if the address is being used already by any other device. This is achieved through a process called Duplicate Address Detection (DAD).
DAD leverages Neighbor Solicitation and Neighbor Advertisement messages.
Suppose, C wants to join the local network. C generates a tentative unicast link-local address using EUI-64 based on its MAC address.
In TCP/IP, we use both IP and MAC addresses.
Dynamic Host Configuration Protocol version 6 is similar to DHCP in IPv4 and its function is to configure IPv6 clients with the information required by an IPv6 device to operate on an IPv6 local network.
In IPv6 a device can get addressing information in 3 ways:
SLAAC refers to the ability of the host’s ability to get addressing information by itself.
Similar to IPv4’s ARP(address resolution protocol), to get link-layer host addresses or connection information of available routers.
NDP operates on the link layer of the OSI model and has the following functions:
Stateless auto-configuration allows a device to connect to the internet without a DHCP server.
Mapping from IP address to a physical address.
Determine that a neighbor is no longer reachable on the link.
Nodes need to check whether an IP address is already in use.
NDP uses Internet Control Message Protocol version…
The IPv6 global unicast address is similar to IPv4 public IP address. It is used when a host wants to use the internet.
This example address shows 8 groups of 16-bit hexadecimal numbers, separated by colons, 128 bit long altogether. Starting with 2001, a global unicast address consists of 3 sections. 2001:1234:ABCD is called a global routing prefix (first 48 bits). 5678 is called the subnet ID (next 16 bits). The third part, 0221:2FFF:FEB5:6E10 is called the interface ID (last 64 bits), which is the host part.
This is a 2-step process. The global routing prefix and the subnet…