In the LAN (Wired Network) each client connects to a switch. The switch is the center point for each client to gain access to the network. The wireless Access Points also connects to the switch. Wireless clients discover nearby APs using their wireless NIC. The wireless Access Points are advertising their SSID for the client. Clients select wireless Access Points and attempt to connect using authentication. After being authenticated, wireless users can access network resources. The wireless Access Points has two types: autonomous APs and controller-based APs.
Autonomous APs
Autonomous APs are useful in situations where only a couple of APs are required in the network. We can configure autonomous APs using the Cisco CLI or a GUI. We can control multiple APs using wireless domain services (WDS) and managed using Cisco Works Wireless LAN Solution Engine (WLSE). The home router is an example of an autonomous AP. In the case of increased wireless demands, more APs would be required. Each AP has its network and operates independently from other APs. The APs can be independently configured. The figure below illustrates the Autonomous APs.
Controller-Based APs
It is server-dependent APs that not need any initial configuration. Controller-based APs are helpful where many APs are required in the network. When a new AP is added to the network, the controller automatically configures and manages the APs. The benefit of the controller is that it can be used to manage many APs. The figure below illustrates the controller-based APs.
A Wireless home router is a device that communicates between the internet and the devices in your home that connect to the internet. It routes traffic between the devices and the internet. Selecting the right kind of router for your home is very important. A wireless home router usually serves as:
Access point– It usually provides connectivity for 802.11a/b/g/n/ac wireless access
Switch—A Wireless home router also contains four full-duplex switch ports with a speed of 10/100/1000 to connect wired devices.
Router– The router server is the default gateway for connecting to other network infrastructures
A wireless router server is a small business or residential wireless access device. It is connected to the Internet Server Provider modem and shares internet services using RF signals. Internal devices wirelessly determine the router by its SSID and attempt to connect and authenticate with it to access the Internet. The SSID is the abbreviation of the Service Set Identifier. The figure below illustrates the workings of the wireless home router.
Most wireless routers provide advanced features, such as high-speed access, video streaming, IPv6 addressing, QoS, configuration utilities, and USB ports to connect printers or portable drives. The quality we should consider when choosing a good router is as follows:
Wi-Fi coverage
Wi-Fi signal availability mostly depends on the home’s size and the barriers preventing signals from reaching their destinations. So, look for a router that has the potential to reach the far-off corners of the home.
Wi-Fi performance
Router technology has changed occasionally, so it selects the latest technology and has updated firmware. The latest technology is the multi-user, multiple-input, multiple-output (MU-MIMO) technology. The MU-MIMO allows the WI-FI router to communicate with multiple devices simultaneously.
Wi-Fi security
Wi-Fi security is an important aspect. Cybercriminals can access your home network and copy your data, install malware and viruses on your devices, and access your personal and financial information. So, having a router providing network-level protection can help protect against cyber-attacks at the port of entry.
A Wireless Network Interface Card (WNIC) is a crucial component that enables devices to connect to wireless networks. It’s a small device that allows your computer, laptop, or other devices to communicate with a wireless router or access point. This article will explore WNICs, their types, installation, security features, and common issues that need troubleshooting.
A wireless network interface card (WNIC) is a network card that connects to a wireless radio-based network. Like other NICs, it functions on Layer 1 and 2 of the OSI Model. It performs the same operation as a normal network card, except it operates wirelessly instead of through network cables. The card contains an antenna to send and receive microwave signals.
Laptops, tablets, and smartphones now all include built-in wireless NICs. However, we can use a USB wireless adapter if a device does not have a built-in wireless NIC. If we need a wireless network interface card (WNIC) in a desktop computer, we can install the WNIC on the PCI bus. The card is also available as a USB and PC card. The figure below illustrates USB WNIC and WNIC for the PC’s expansion slot.
Types of Wireless Network Interface Card (WNIC)
WNICs come in various forms, including:
PCI WNICs: These WNICs are suitable for desktop computers and are installed in a computer’s PCI slot.
USB WNICs: Connected via USB, these WNICs are ideal for laptops and devices with USB ports.
PCIe WNICs: Installed in a computer’s PCIe slot, these WNICs offer faster speeds and are suitable for high-performance devices.
Mini-PCIe WNICs: Smaller than PCIe WNICs, these are used in smaller devices like laptops and netbooks.
M.2 WNICs: Installed in a computer’s M.2 slot, these WNICs offer high-speed connectivity and are suitable for modern devices.
Installation and Compatibility
Installing a WNIC requires consideration of compatibility with your device and operating system. Ensure the WNIC is compatible with your device’s operating system (Windows, macOS, Linux, etc.) and follows these steps:
Shut down your device.
Locate an available slot (PCI, USB, PCIe, etc.).
Insert the WNIC into the slot.
Install device drivers from the manufacturer’s website or include a CD.
Configure your wireless network settings.
Security Features
WNICs offer various security features to protect your wireless connection:
Encryption: WEP, WPA, WPA2, and WPA3 encryption methods secure your data.
Authentication: 802.1X authentication protocols ensure only authorized devices connect.
Firewall: Built-in firewalls block unauthorized access to your device.
Slow speeds: Upgrade your WNIC, check for interference, and optimize your wireless settings.
Driver updates: Regularly update your WNIC drivers to ensure compatibility and performance.
Comparison with Other Wireless Technologies
WNICs differ from other wireless technologies like:
Wi-Fi Adapters: External devices that provide wireless connectivity.
Mobile Hotspots: Devices that create a wireless network using cellular connectivity.
Bluetooth: A wireless technology for device-to-device communication.
Conclusion and Future Outlook
WNICs play a vital role in enabling wireless connectivity. As wireless technology advances, we can expect faster speeds, improved security, and increased reliability. Emerging trends like Wi-Fi 6 and 5G will further enhance WNIC capabilities. By understanding WNICs and their features, you can make informed decisions when selecting and installing wireless network interface cards.
A WLAN allows devices to connect and communicate without using wires or cables. However, traditional wired LAN devices communicate over Ethernet cables. Both WLAN and LAN share a similar origin. The IEEE has chosen the 802 network standards for LAN/MAN portfolios of computer network architecture.
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The two primary 802 standards are 802.3 Ethernet and 802.11 WLAN. However, there are significant differences between both. Wireless LANs use Radio Frequencies instead of cables at the physical layer and MAC sublayer of the data link layer. The main differences between WLAN and LAN are as follows:
The first difference is that 802.13 uses Ethernet cable, while 802.11 uses RF waves. The RF allows data frames to travel without wire and is available to anyone receiving the RF signal.
RF is insecure from outside signals, but the cable is in an insulating sheath. Radios working alone in the same geographic area but using the same or a similar RF can interfere with each other. The signal varies as it reflects, refracts, and is lost depending on the environment.
In the WLAN, radio stations could start playing over each other when the RF signal travels further away from the source, and static noise would increase. Finally, the signal would be lost. However, LANs have cables of appropriate lengths to maintain signal strength.
Wireless LAN is more susceptible to attacks because it is more exciting. However, in the LAN, attacks depend on who and what was installed into devices and what is being connected.
Wireless LANs involve additional regulations and standards not applied to wired LANs.
Wireless APs and wireless Routers have a limit of several users connected to a single Wireless Router, depending on the type of Wireless Router. However, LAN depends on the number of Ethernet ports a router or a switch has. We can increase the number of ports by adding additional switches.
WLAN 802.11 advised collision avoidance (CSMA/CA) instead of collision detection (CSMA/CD) for media access to dynamically avoid collisions within the media.
WLANs’ frame format differs from wired Ethernet LANs, so they require additional information in the Layer 2 header of the frame.
WLANs increase privacy issues because radio frequencies can reach anyone outside the required location.
We can summarize in a table as is under
Aspect
WLAN (Wireless Local Area Network)
LAN (Local Area Network)
Connection Method
Wireless (via radio frequency signals, Wi-Fi)
Wired (via physical cables, such as Ethernet)
Range
Limited by signal strength and obstructions
Limited by cable length
Mobility
Limited devices are typically stationary
Generally more accessible, no need for physical cables
Installation
Generally easier, no need for physical cables
Requires laying cables and infrastructure
Speed and Reliability
May vary due to signal interference and distance
Generally fast and reliable with wired connections
The IEEE 802.11 WLAN represents the IEEE designation for wireless networking. IEEE 802.11 standard defines how RF in the unlicensed ISM frequency bands is used for the physical layer and the MAC sub-layer of wireless links. Several implementations of the IEEE 802.11 standard has defined by IEEE over the years. All the standards use the Ethernet protocol and the CSMA/CA access method. The highlights of these standards are:
802.11– 802.11 was released in 1997. This is the original WLAN standard. The operating frequency of that standard is 2.4 GHz band. The speeds of this standard are up to 2 Mbps. This standard is now obsolete. When 802.11 standards were providing 2 Mbps speed, at the same time wired LANs was operating at 10 Mbps speed.
IEEE 802.11a– 802.11a was released in 1999. The speed of this standard is 54 Mbps and the operating frequency is 5GHz. It is incompatible with the 802.11b and 802.11g wireless standards. Due to high frequency, the coverage area of this standard is smaller and the devices contain one antenna for transmission and reception of signals.
IEEE 802.11b– The standard was released in 1999. Operating frequency of this standard is 2.4 GHz and offering speed is up to 11 11Mbps. The range of devices with 802.11b standard is long-range than 802.11a because the operating frequency is lower than 802.11a. The devices can better penetrate building structures than devices based on 802.11a standard. Wireless devices contain a single antenna to transmit and receive signals.
IEEE 802.11g– 802.11is a popular wireless standard today is the successor of 802.11b. It was released in 2003. The operating frequency is 2.4 GHz band; the standard offers speeds of up to 54 Mbps. The frequency band is the same as 802.11b but with better speed than 802.11b. The devices have one antenna to transmit and receive wireless signals. It is also compatible with 802.11b. The speed of the device is reduced when supporting an 802.11b client.
IEEE 802.11n– This is the first standard specify MIMO, was released in 2009. The standard allows operating with two frequencies – 2.4 GHz and 5 GHz and is referred to as a dual-band device. The data rates range is between 150 Mbps to 600 Mbps covering the distance range of up to 70 m. APs and wireless client using 802.11g required multiple antennas for multiple-in multiple-out (MIMO) technology. MIMO required multiple antennas for both the transmitter and receiver. Up to four antennas can be used with 802.11n devices. The standard is also is backwards compatible with 802.11a/b/g devices.
IEEE 802.11ac– Current home wireless routers are likely 802.1ac-compliant, and operate in the 5 GHz frequency space was released in 2013, providing data rates ranging from 450 Mbps to 1.3 1300 Mbps. It also uses MIMO technology to get better communication performance. The standard can support up to eight antennas. The standard is backwards compatible with 802.11a/n devices but it limits the expected data rates.
IEEE 802.11ad– The standard is expected to be approved in November 2019. It is also known as “WiGig”, uses tri-band: 2.4 GHz, 5 GHz, and 60 GHz, and offers theoretical speeds of up to 7 Gbps. However, this speed can achieve only if the client device is situated within 3.3 meters or 11 feet of the access point. Because 7 Gbps speed is possible on 60 GHz which required line-of-site, therefore, it cannot penetrate through walls. It switches to 2.4 GHz and 5 GHz bands for backward compatibility with existing Wi-Fi devices. The compatibility environment limits the expected data rates.
The table below illustrates the comparison between all IEEE 802.11 standards including the backwards compatibility.
Radio frequencies refer to the rate of oscillation of electromagnetic radio waves in the range of 3 kHz to 300 GHz. This band is used for communications transmission and broadcasting. Different radio frequencies are useful for different wireless technologies. For example, some frequencies are used for radio broadcasting, and others are used for television broadcasting.
Radio waves are used in many different types of communication, which are defined in the electromagnetic spectrum. The electromagnetic spectrum contains all the frequencies of electromagnetic waves, including visible light waves, microwaves, and radio waves. The radio wave spectrum is included in the electromagnetic wave spectrum, having a frequency range between 3 kHz and 300 GHz.
The radio frequency spectrum is divided into radio frequency bands for many applications, including AM Radio, FM radio, television, cellular networks, Bluetooth, walkie-talkies, satellite communications, and military applications. All wireless devices operate in the radio frequency range of the electromagnetic spectrum.
The International Telecommunication Union – Radiocommunication Sector (ITU-R) is responsible for allocating radio frequencies from the spectrum. The radio frequency bands are allocated for different purposes. Some bands in the electromagnetic spectrum are used for applications such as air traffic control and emergency responder communications networks. Some bands, such as the Industrial, Scientific, and Medical Band (ISM) and the unlicensed National Information Infrastructure (UNII) band, are license-free.
The frequency range for wireless communication is 3 Hz to 300 GHz. The WLANs, Bluetooth, cellular, and satellite communication all operate in the microwave UHF, SHF, and EHF ranges. The WLAN frequency is 2.4GHz ISM bands and 5 GHz UNII bands. Specifically, the following frequency bands are allocated to 802.11 wireless LANs:
4 GHz (UHF)- 802.11b/g/n/ad
5 GHz (SHF)- 802.11a/n/ac/ad
60 GHz(EHF) – 802.11ad
The components of the electromagnetic spectrum are gamma rays, X-rays, ultraviolet, visible light, infrared, microwaves, and radio waves. We will discuss radio waves in detail. Radio waves have the longest wavelengths, from a few centimeters to thousands of meters. The Tagle below illustrates the radio frequency band.
Frequency Range
Band
Wavelength Range
Extremely Low Frequency (ELF)
3 Hz – 30 Hz
100,000 km – 10,000 km
Very Low Frequency (VLF)
30 Hz – 300 Hz
10,000 km – 1,000 km
Low Frequency (LF)
300 Hz – 3 kHz
1,000 km – 100 km
Medium Frequency (MF)
3 kHz – 30 kHz
100 km – 10 km
High Frequency (HF)
30 kHz – 300 kHz
10 km – 1 km
Very High Frequency (VHF)
300 kHz – 3 MHz
1 km – 100 m
Ultra High Frequency (UHF)
3 MHz – 30 MHz
100 m – 10 m
Super High Frequency (SHF)
30 MHz – 300 MHz
10 m – 1 m
Extremely High Frequency (EHF)
300 MHz – 3 GHz
1 m – 10 cm
Tremendously High Frequency (THF)
3 GHz – 30 GHz
10 cm – 1 cm
Very Tremendously High Frequency (VTHF)
30 GHz – 300 GHz
1 cm – 1 mm
Tremendously Very High Frequency (TVHF)
300 GHz – 3 THz
1 mm – 0.1 mm
Extremely Tremendously High Frequency (ETHF)
3 THz – 30 THz
0.1 mm – 0.01 mm
Very Extremely Tremendously High Frequency (VETHF)
Wireless technologies refer to technology that makes it possible to communicate over a distance without using wires or any other conductors. We can use wireless technologies for both long and short distances. Wireless technologies networks are based on electromagnetic waves, such as radio frequencies (RF), infrared (IR), satellites, etc.
Remember when Wi-Fi was a luxury and 5G sounded like science fiction? Wireless technologies have come a long way since the first radio signals, but the last five years have been a game-changer. Today, we’re not just connecting devices—we’re powering smart cities, remote surgeries, and even Mars rovers. Let’s break down what’s new, what’s obsolete, and why your next gadget might need a wireless upgrade.
The Wireless Technologies We Use Every Day (And What’s Changed)
Wi-Fi: From “Buffering” to “Blazing-Fast”
In 2019, Wi-Fi 5 (802.11ac) was the gold standard, offering speeds up to 3.5 Gbps. Fast forward to 2024, and Wi-Fi 6E is the new norm. Here’s why it matters:
No More Traffic Jams: Wi-Fi 6 uses OFDMA (think “carpool lanes for data”) to serve multiple devices simultaneously. It is perfect for homes with 50+ smart gadgets.
Wi-Fi 6E Adds Rocket Fuel: It unlocks the 6 GHz band, reducing interference and boosting speeds up to 9.6 Gbps and streaming 8K? No problem.
Wi-Fi 7 is expected to be the latest standard of Wi-Fi, also known as IEEE 802.11be. It promises latency under 1 millisecond, ideal for VR gaming and real-time collaboration. It provides speed to the User PC up to 5Bbps. Wi-Fi 7 is faster 4.8 times than Wi-Fi 6 and 13 Times than Wi-Fi 5.
What’s Obsolete?
Wi-Fi 5 routers struggle in crowded smart homes.
Pro Tip: If your router is older than 3 years, it’s time for an upgrade.
5G: More Than Just Faster Phones
In 2019, 5G was rolling out with mixed reviews—spotty coverage and overheating phones. Today, it’s a whole new ballgame:
Standalone 5G (SA): No more relying on 4G towers. This pure 5G network offers ultra-low latency for self-driving cars and drone deliveries.
mmWave Isn’t Dead: Despite early hiccups, cities like NYC and Tokyo now use mmWave for multi-gigabit speeds in stadiums and airports.
5G-Advanced (2024): This upgrade focuses on AI-driven networks. Imagine your phone predicting congestion and switching towers before you notice buffering.
Real-World Impact:
Farmers use 5G sensors to monitor soil health in real time.
Hospitals perform remote surgeries with near-zero lag.
IoT—The Silent Revolution
IoT refers to a network of interconnected physical devices embedded with sensors, software, and connectivity, enabling them to collect, exchange, and act on data. These devices range from everyday objects (e.g., smart appliances) to industrial machines.
Smart Homes Finally Work Together
Matter 1.2 (2024): A unified standard for Alexa, Google Home, and Apple. Finally, your smart fridge won’t fight your thermostat.
Wi-Fi HaLow: Do you need sensors within a 1-mile radius? This long-range, low-power Wi-Fi variant connects agricultural sensors or warehouse trackers.
Industrial IoT: Factories Get a Brain Transplant
Private 5G Networks: Companies like BMW and Airbus build dedicated 5G networks for factories. What are the benefits for industries?
Zero downtime for robotic arms.
Real-time quality checks using AI cameras.
Time-Sensitive Networking (TSN): Machines now “talk” in sync, with microsecond precision.
Security—Locking Down the Airwaves
WPA2 encryption was the star in 2019, but hackers have upped their game. The updated security are as under:-
WPA3: Your New Best Friend
No More “Password Guessing”: WPA3 uses Simultaneous Authentication of Equality (SAE)—guess wrong once, and the system locks out hackers.
Encryption for Public Wi-Fi: Connect to a coffee shop’s network? Your data’s now automatically encrypted.
The Quantum Threat (Yes, It’s Real)
Post-Quantum Cryptography: Future quantum computers could crack today’s codes. NIST’s new algorithms (coming 2024) aim to fix this.
Simple Advice for 2025:
Replace old routers (they probably lack WPA3).
Use a VPN on public networks.
Health, Myths, and Sustainability – Wireless Technologies Cutting Through the Noise
5G Radiation: What Science Says in 2024
In 2019, debates about 5G’s health risks were fueled by misinformation and fear of the unknown. Let’s set the record straight with 2023–2024 updates:
WHO’s 2023 Report: After reviewing 1,400+ studies, the World Health Organization confirmed “no short-term health risks from 5G within international safety limits.” The key phrase? “Short-term.” Long-term studies are ongoing, but panic isn’t necessary.
Why the Fear? Misleading viral videos (like 5G towers “causing COVID”) still haunt social media. The truth? 5G uses non-ionizing radiation—the same type as your microwave and FM radio. It can’t break DNA bonds like X-rays or UV light.
Real-World Safeguards:
Lower Emission Limits: The EU updated its guidelines in 2023, reducing allowed exposure by 50%.
Smart Tower Designs: New 5G antennas focus signals like a flashlight instead of blasting energy everywhere.
What You Can Do:
Use a hands-free headset for long calls.
Don’t sleep with your phone under your pillow (yes, people still do this).
Part 5: The Future – 6G, Satellites, and Invisible Networks
6G: Beyond Speed, Toward Sci-Fi
While 5G is still rolling out, researchers have already dreamed of 6G (targeting 2030). Here’s what’s brewing in labs:
Terahertz Waves: These super-high frequencies (above 100 GHz) could deliver 1 Terabit/second speeds—enough to download 10 HD movies in a blink.
Catch: They struggle with walls and rain. Solution? Hybrid networks blending 6G + 5G + Wi-Fi.
AI-Native Networks: Your phone will predict when you’ll binge Netflix and reserve bandwidth in advance.
Holographic Calls: Companies like NTT Docomo are testing 3D holograms for meetings. Imagine presenting to a colleague’s lifelike avatar!
Who’s Leading the Race?
China (Huawei) and South Korea (Samsung) aim to launch 6G trials by 2026.
The U.S. and EU are focusing on ethical AI integration to avoid bias in network algorithms.
Satellite Internet: Blanketing the Globe from Space
Elon Musk’s Starlink made headlines in 2019, but 2024 is the year satellite internet goes mainstream.
How It Works: Thousands of low-Earth orbit (LEO) satellites beam internet to pizza-box-sized dishes on your roof.
Speed Boost: Starlink’s Gen 3 satellites now hit 500 Mbps—rivaling cable broadband.
Not Just Starlink: Amazon’s Project Kuiper plans to launch 3,236 satellites by 2026, while the EU’s IRIS² will focus on rural areas.
Who Needs It?
Adventure Bloggers: Stream live from the Sahara Desert.
Disaster Zones: Ukraine used Starlink to stay online during blackouts.
The Catch:
Space Junk: With 7,500+ satellites already orbiting Earth, collisions are a risk. Fix? New “de-orbiting” rules require satellites to burn up after retirement.
Lag Time: Satellite signals take 20–40 milliseconds to reach Earth—fine for Zoom calls but not for Fortnite.
Invisible Networks: The Rise of Ambient IoT
Forget wearables—ambient IoT lets everyday objects (like shoes or cereal boxes) connect to the internet without batteries.
How? Tiny sensors harvest energy from Wi-Fi signals, light, or motion.
Walmart’s Pilot: The retail giant uses battery-free RFID tags to track inventory. No more “out of stock” surprises.
What This Means for You
By 2025:
Your car might get updates via satellite during road trips.
Smart mirrors could use 6G to stream AR makeup tutorials.
By 2030:
Smart Dust: Sand-grain-sized sensors in soil could monitor climate change.
Brain-Computer Interfaces: Neuralink-like devices could use 6G to transmit thoughts (yes, really).
Final Word:
Wireless technologies future isn’t just about faster—it’s about smarter, greener, and more inclusive connections. Whether you’re a gamer, farmer, or someone who hates buffering, there’s something here for everyone.
Wireless Communication is the fastest-growing and most vibrant technological area in the communication field. It can provide client mobility, the ability to connect from any location and at any time, and the ability to roam while staying connected. It is the technique of transmitting information from one point to another without using any connection like wires, cables, or any physical medium.
A WLAN is a wireless network commonly used in homes, offices, and campus environments. WLAN uses radio frequencies instead of cables, usually applied in a switched network. The frame format of the WLAN is similar to Ethernet. The transmitter transmits data in the WLAN, and the receiver receives data within a few meters.
Remote TV control and satellite communication can be carried out over thousands of kilometers. The current business environments need network connectivity while people are on the move. The current network supports connectivity during the move, and people can use multiple devices, such as laptops, tablets, and smartphones. Different types of architecture make this possible. The most important, from a business point of view, is the wireless LAN (WLAN).
Benefits of Wireless
It has many benefits for both the business environment and the at-home environment. The important benefits are the following:
Increased efficiency
Wireless networks improve data communications between businesses, partners, and customers.
Access and availability
A wireless network allows users to communicate while on the move, such as using a cell phone. We don’t need any cables or adaptors to access the network.
Flexibility
The wireless network provides services to workers without them sitting at dedicated computers. They can carry on productive work while away from the office. This is a modern style of working; the worker can work directly from home.
Cost savings
Wireless networks are also a cost-saving option for corporate and home users. They are an easy and cheaper way of networking, especially in buildings or where the property owner does not permit the installation of cables.
In this lesson, I am going to configure EtherChannel. EtherChannel in networking has a set of restrictions that state what you can do and what you cannot do. Before configure and establish the EtherChannel, it is important to know the restrictions. Here are some basic restrictions and guidelines on setting up EtherChannel:
EtherChannel support– Ethernet channel support on all interfaces must support with no requirement that interfaces be physically adjacent, or on the same module.
Speed and duplex– For EtherChannel configuration, all interfaces which joining the Channel must be operated with the same speed and duplex settings.
VLAN match– All interfaces in one EtherChannel bundle must be the member of the same VLAN, or be configured as a trunk.
Range of VLAN– An EtherChannel supports the same allowed range of VLANs on all the interfaces in a trunking EtherChannel. If the allowed range of VLANs is not the same, the interfaces do not form an EtherChannel, even when set toautoordesirable
Maximum Ports in Channel Group – We can assign up to eight ports to a channel group. Using LACP, we can configure 16 ports in the port group, eight ports can be active and the other eight ports are in Standby mode. This configuration is very useful when the active group is loose, the standby links will activate immediately.
EtherChannel between Different Switches – PAgP is a Cisco propriety protocol, and LACP is an open standard protocol. If we need to create EtherChannel with switches from other vendors, we will configure EtherChannel using LACP.
EtherChannel Connection Modes – EtherChannel uses two types of Protocols LACP and PAgP. LACP also has two configuration modes, Active and Passive. The PAgP is also two modes Auto and Desirable. LACP Active link attempts to start LACP session by sending out LACP negotiation packets and Passive link only respond to packets that it receives. Passive mode never starts a negotiation. As with Active link in LACP, Auto links in PAgP start negotiation, the PAgP Desirable is the same to LACP Passive links waiting for PAgP negotiation packet.
Select and identify the interfaces that will create the EtherChannel group. Then enter the“interface rangeinterface_range” command in global configuration mode. Using the “range” keyword allows you to select multiple interfaces and configure them all at once.
The command syntax for creating a channel group is “channel-groupidentifiermode activecommand in interface range configuration mode. The identifier identifies a channel-group number. Themode can be active/passive/on The keywords active/ passive identify that this as an LACP EtherChannel.
By default, EtherChannel is disabled on Cisco switches. For EtherChannel verification, there are several commands we can use. The first command we can use to verify the EtherChannel is “show interface port-channel”command. The output of this command displays the general status of the port channel interface.
When several port-channel interfaces are configured on the same device, use theshow EtherChannel summarycommand to simply display one line of information per port channel. In Figure 2, the switch has one EtherChannel configured; group 1 uses LACP. The figure below illustrates the output of this command.
We can use the show “etherchannel port-channel” command display full information about a particular port channel interface, The figure below illustrates the output of this command.
We can display role information about any physical interface which is a member of an EtherChannel bundle using the “show interfaces etherchannel”command.
EtherChannel is used to bundle physical links into a single logical link. We can bundle a maximum of 8 physical links into one logical link. When physical links are bundled into a single logical link, the STP only sees one and cannot block anything.
Two types of protocols are used for EtherChannel: Port Aggregation Protocol (PAgP) and Link Aggregation Control Protocol (LACP). EtherChannel protocols remove loops within the physical links.
The EtherChannel protocols also maintain a record of each physical link. In case of any physical link failure or restoration, the protocols manage the deletion and addition of the link without informing the STP about the change. Cisco switches use the IEEE standard Link Aggregation Control Protocol (LACP) and Cisco’s proprietary Port Aggregation Protocol.
Each EtherChannel is called a channel group. We can add a physical port into the group using the “channel-group group-number mode on” command in the interface configuration mode. We can also create and configure the EtherChannel without using PAgP or LACP. This type of EtherChannel is called a static or Unconditional EtherChannel.
Port Aggregation Protocol (PAgP)
Port Aggregation Protocol is a Cisco-proprietary protocol that can only work on Cisco switches or switches licensed by vendors to support Port Aggregation Protocol. The protocol helps automatically create EtherChannel using the exchange of PAGP packets.
Port Aggregation Protocol packets are exchanged between EtherChannel-capable ports to negotiate the establishment of a channel. The protocol also checks for configuration stability and manages link additions and failures between two switches. It ensures that when an EtherChannel is created, all ports have the same type of configuration.
PAGP packets contain all the information of the neighbor switch. The receiving switch learns the neighbor switch identity capability of supporting PAGP and then dynamically groups similarly configured ports into a single logical link. When PAgP is enabled, the PAgP packets are sent after every 30 seconds. The Port-Aggregation Protocol (PAgP) uses the layer 2 multicast address 01-00-0C-CC-CC-CC.
To establish EtherChannel, all ports must have the same data speed, duplex setting, and VLAN information. Any modification to the port configuration can affect all other channel ports. The figure shows the modes for the Port Aggregation Protocol.
On—Interfaces configured with this mode do not exchange PAgP packets. On mode forces the interface to channel without PAgP or LACP. A port with “on” mode will create an EtherChannel only when another interface group isin EtherChannel “on” mode.
PAgP desirable—The interface with PAgP desirable mode remains in an active negotiating state, initiating negotiations with other interfaces by sending PAgP packets every 30 seconds.
PAgP auto—An interface with PAgP auto mode is in a passive negotiating state. In this state, the interface replies to the PAgP packets received but does not initiate any Port Aggregation Protocol negotiation.
For establishing EtherChannel, compatibility of the modes on both sides is important. For example, if one side is configured to be in auto mode, waiting for the other side to initiate the EtherChannel negotiation.
If the other side is also set to auto, the PAgP packet will never exchange, and the EtherChannel will not form. If all modes are disabled or no mode is configured, then the EtherChannel is disabled. The figure below illustrates the mode of the Port Aggregation Protocol for EtherChannel establishment.
The on mode manually sets the interface in an EtherChannel without any negotiation. If one side is set to on, the other side must be set to for establishing EtherChannel. Suppose the other side is set to negotiate parameters through the Port Aggregation Protocol. In that case, the EtherChannel is impossible because the side set to on mode does not negotiate. The EtherChannel configuration for the above topology is as follows:
Note:- PAgP Modes are On, Desirable, Auto
Switch1
Switch1(config)#interface range e0/0-3
Switch1(config-if-range)#channel-group 1 mode auto
Switch1(config-if-range)#interface port-channel 1
Switch1(config-if)#switchport mode trunk
The Port Aggregation Protocol does a configuration check on participating interfaces and confirms that the neighboring interfaces also use the Port Aggregation Protocol. The Port Aggregation Protocol interfaces that don’t have similar configurations will not participate, and we won’t get an accidental switching loop.
LACP
LACP is an open protocol published by IEEE under the 802.3ad specification. The IEEE also released a new definition of the LACP in the IEEE 802.1AX standard for local and metropolitan area networks. LACP similarly allows several physical ports to be bundled to establish a single logical channel.
It allows a switch to negotiate an automatic bundle using the LACP packets. The function of the LACP is similar to that of PAgP with Cisco EtherChannel. The difference is that LACP is an IEEE standard, and PAgP is Cisco Propiaritry. The LACP is used to establish EtherChannels in multivendor environments. We can use both protocols on Cisco devices. The LACP uses multicast address 01-80-c2-00-00-02.
LACP functions the same way and has the same negotiation benefits as PAgP. It helps establish the EtherChannel link by detecting each side’s configuration and checking compatibility. The figure shows the different modes for LACP.
On—similarly, the on mode ensures the interface to channel without LACP. Interfaces with this mode do not exchange LACP packets.
LACP active– The active mode places a port in an active negotiating state. The port starts negotiations with other ports by sending LACP packets.
LACP passive—The passive mode places a port in a passive negotiating state. In this mode, the port responds to the LACP packets it receives; however, the passive port does not initiate LACP packet negotiation.
Similar to PAgP, modes must be compatible for establishing EtherChannel. The on mode is repeated because it creates the unconditional EtherChannel configuration without PAgP or LACP dynamic negotiation. The simple configuration of LACP for the above topology is as follows:
Note:- LACP Modes are On, Active, Passive
Switch1
Switch1(config)#interface range e0/0-1
Switch1(config-if-range)#channel-group 1 mode active
Switch1(config-if-range)#interface port-channel 1
Switch1(config-if)#switchport mode trunk
The LACP configuration is almost the same as the PAgP configuration. The difference is only the use of the keywords. The keywords used by LACP are active and passive. The active keyword shows that the interface uses the LACP protocol. The passive keyword indicates the use of LACP; however, it can only respond to requests but cannot send any LACP packet.
