All updated 2024 lessons of CCNA 200-301 v1.1. We cover all CCNA Lessons v1.1 in our CCNA 200-301 Course and Self-Paced Training.
TCP vs UDP. The difference between TCP and UDP. A Comparison of Speed, Security, Header, ports, applications used by UDP and TCP.
CertificationKits provides you with Our Cisco CCNA Lab kits 200-120 study guide, cisco routers, and cisco switches for test preparation.
Follow @ASM_Educational Click here to see the presentation Cisco CCNA-Port Security Here what I have: Pc1=10.10.10.1 pc2=10.10.10.2 pc3=10.10.10.3 connected to port f0/3 which is located in Lobby hacker=10.10.10.4 The goal is I want to protect the port f0/3 located in lobby and make sure only PC3=sales3 be able…
In Cisco Packet Tracer Configuration Examples, you will find Cisco Router and Switch Configurations for CCNA, CCNP and CCIE Certifications.
Cisco CCNA Training, Tips, Blogs, Notes, and Practice Test.
What is a VLAN? VLANs (Virtual LANs) are the Logical Networks that you can seperate big switched networks into smaller networks.
Subnetting Cheat Sheet will help you during your IPv4 Address and Subnetting Mask Configurations. You can use it Online or you can Download it
Subnetting Cheat Sheet will help you during your IPv4 Address and Subnetting Mask Configurations. You can use it Online or you can Download it
In Cisco Packet Tracer Configuration Examples, you will find Cisco Router and Switch Configurations for CCNA, CCNP and CCIE Certifications.
Subnetting Cheat Sheet will help you during your IPv4 Address and Subnetting Mask Configurations. You can use it Online or you can Download it
DNS is a protocol that is used to translate hostnames to the IP addresses. We will explain, "What is DNS?" and DNS Server. what dns server
Two types of ACLs are Standard Access-Lists & Extended Access-Lists. Here we will learn Cisco Standard ACL Configuration with Packet Tracer.
In this lesson, we will learn Cisco Voice VLAN Configuration. We will configure Voice VLAN on Cisco switches.
Network Cabling and Cable Types: Ethernet 10Base-T, Fast Ethernet 100Base-T, Gigabit Ethernet 1000Base-T, 10 Gigabit Ethernet 10000Base-T
In Cisco Packet Tracer Configuration Examples, you will find Cisco Router and Switch Configurations for CCNA, CCNP and CCIE Certifications.
Free 300-page Cisco CCNA Lab Guide with complete exercises and solutions covering everything on the latest CCNA 200-301 exam.
Follow @ASM_Educational Cisco CCNA-Router on Stick Inter VLAN Communication (Router on Stick) Earlier we built and tested the following topology: Now that we have a better understanding of how routers work, we will solve the problem of inter VLAN communication with a different solution. The problem with the…
Motherboards – Connect everything together. Typical form factors include ATX (most common), microATX, ITX, and BTX. AMD and older intel chipsets include a northbridge that connects the CPU, RAM, and x16 PCIe devices, and southbridge that connects secondary systems such as USB, SATA, IDE, and sound. Types of expansion buses…
Follow @ASM_Educational Cisco CCNA CCNP VACL Configuration Now I will do small Lab: In This Lab I have 6 host connected to a Switch, with Ip address as follow 200.1.1.x where x=Router number, I will go to my multi-layer switch and configure VACL=VLAN Access-list My host in here act as…
In this page you can find wireless network tools, wireless network analyzers. You can download these wireless tools and use.
VLAN Frame Tagging Protocols (ISL and dot1.q) In this lesson, we will learn VLAN Frame Tagging Protocols detailly. In the next lessons, you can also check
Ping Command is the most used command by Network Engineers.Here,we ll see Ping Command for Windows, for Linux, for Unix detailly.
In Packet Tracer Router DHCP Example, we will focus, DHCP Configuration with Packet Tracer.We will learn How to Configure DHCP Server and ip helper command.
All updated 2024 lessons of CCNA 200-301 v1.1. We cover all CCNA Lessons v1.1 in our CCNA 200-301 Course and Self-Paced Training.
Network Cabling and Cable Types: Ethernet 10Base-T, Fast Ethernet 100Base-T, Gigabit Ethernet 1000Base-T, 10 Gigabit Ethernet 10000Base-T
Learn Basic Networking course in New Delhi, India. Get certified and be an expert in network installation, configuration, & troubleshooting.
|➨ Aprenderás sobre UDP (User Datagram Protocol): Cómo funciona, para qué se utiliza y su comparación con TCP.✅
Computer port In computer hardware, a port serves as an interface between the computer and other computers or peripheral devices. In computer terms, a port generally refers to the female part of connection. Computer ports have many uses, to connect a monitor, webcam, speakers, or other peripheral devices. On the physical…
The OSI model describes seven layers that computer systems use to communicate over a network. Learn about it and how it compares to TCP/IP model.
Subnet masking is one of those "black magic" topics of networking that you either get or you don't. Unfortunately, most published explanations of subnet masking do a very poor job of explaining it to the lay person or to the beginning IT engineer. Accordingly, this blog post is an attempt to offer a simple explanation for people who need to understand this. The contents of this blog primarily come from the EnGenius Certified System Engineer training course, written by Jason D. Hintersteiner, Copyright 2014-2015. What is a subnet mask? When configuring a static IPv4 address on a network device (i.e. PC, laptop, network switch, AP, etc.), you need to provide at least four parameters: IP Address: This is the unique 32 bit address of the network device Subnet Mask: This defines the scope (i.e. size) of the LAN Default Gateway: This defines the location of the router on the LAN which will route traffic intended for external networks (e.g. Internet) DNS Server(s): These define the IP addresses of domain name resolution (DNS) servers to convert human-friendly (well, friendlier) server names (e.g. www.emperorwifi.com) into its corresponding IP address (e.g. 173.194.206.121). The subnet mask, therefore, defines the size of the local area network (LAN), so that the device can determine whether other network devices it communicates with are on the internal LAN or on the external wide area network (WAN). Why do we distinguish between LAN and WAN? Quite simply, a network device needs to know how to address traffic. Every network interface card (NIC), whether wired or wireless, has a MAC address. This is a unique 48 bit address, expressed in 6 hexadecimal octets as in 88:dc:96:ab:cd:ef, that is burned into the hardware when the NIC is manufactured (though it can be spoofed in most operating systems). When network devices intercommunicate, the first address used in that communication is the MAC address, not the IP address. MAC addresses, though, do not leave the realm of a LAN. If two devices are on the same LAN, they will communicate directly by specifying each other's MAC addresses. Note that the gateway / router is not involved in this communication, and will probably never even see the traffic depending on how the network is structured. When a device wants to communicate with another device not in the LAN, the device communicates to the MAC address of the default gateway, which in turn routes the traffic on to the WAN. How is a subnet mask structured? By definition, a subnet mask must be of equal length to the IP address, as it is used as a filter to express what portion of the IP address is "local" vs. global". In IPv4, therefore, the subnet mask is a 32 bit number, usually expressed in dotted decimal notation. Similarly, in IPv6, the subnet mask is a 128 bit number expressed in hex. Unlike an IP address, however, a subnet mask only has a specific set of values. To understand this, it makes more sense to look at the subnet mask in binary. The subnet mask consists of a contiguous set of "1"s followed by a contiguous set of "0"s. The "1"s indicate the bits in the IP address used for comparison - when that portion of the IP address matches between two hosts, the two hosts are on the same LAN. If that portion of the address doesn't match, then they are on different networks and traffic must be sent through a router / gateway in order to communicate. As a shorthand, classless inter-domain routing (CIDR) notation is used with a "/" after the IP address. The CIDR notation is actually more intuitive than the dotted decimal notation, as it indicates the number of "1"s in the subnet mask. The following table shows the complete set of valid IPv4 subnet masks. The larger the subnet, the lower the CIDR number, and the more hosts that can share the same LAN. The total number of devices on the LAN is 2^(32 - CIDR). Practical Examples and Reserved Addresses Most consumer and enterprise equipment come with a 255.255.255.0 or /24 subnet mask by default, and this is the one people are generally familiar with. A network that is 192.168.0.0/24 means that it has 256 total addresses on the LAN [i.e. 2^(32-24) = 2^8 = 256] with an address range of 192.168.0.0 - 192.168.0.255. A network that is 192.168.0.0/28 means that it has 16 total addresses on the LAN [i.e. 2^(32-28) = 2^4 = 16] with an address range of 192.168.0.0 - 192.168.0.15. A network that is 192.168.0.0/21 means that it has 2048 addresses on the LAN [i.e. 2^(32-21) = 2^11 = 2048] with an address range of 192.168.0.0 - 192.168.7.255. In IPv4, there are also reserved addresses, as follows: Network Address: This identifies the subnet. This is always the first address of the range. Broadcast Address: This is the address that is used to communicate broadcast messages to all devices within a LAN. (An example is DHCP responses from the DHCP server). This is always the last address of the range. The network address and the broadcast address must be defined with the subnet mask in order to provide context. As an example, the three networks above (192.168.0.0/24, 192.168.0.0/28, 192.168.0.0/21) all have the same network address, namely 192.168.0.0, but different broadcast addresses (i.e. 192.168.0.255, 192.168.0.15, 192.168.7.255). Similarly, two different networks can share the same broadcast address (e.g. 192.168.7.255 is a valid broadcast address for 192.168.0.0/21 as well as 192.168.7.0/24). One additional note, because of the network address and broadcast address, the number of LAN addresses that can be used for hosts is always 2 less than the number of addresses on the subnet. It is actually 3 less, because a host address has to be reserved for the gateway to route traffic to the external network (e.g. the Internet). By convention and convenience, the gateway is assigned to either the first or the last usable host IP address (e.g. 192.168.0.1 or 192.168.0.254 in our 192.168.0.0/24 example), though strictly speaking it can be any valid host address on the subnet. Why Do We Care? We care about subnet masking when architecting wired and wireless networks, to ensure that we can accommodate all of the hosts we expect to see on the network. As the number of devices per user continues to increase (who doesn't have a smartphone, tablet, e-reader, and laptop when they travel, and perhaps a game console and other network-enabled devices as well), and as the IoT trend introduces a torrent of small devices on our person and in our environments to measure all sorts of things, the typical 255.255.255.0 subnet mask is no longer sufficient. Take the example of a 100 room hotel that has a guest network. We generally want all of our guests on the same subnet, to facilitate their ability to wirelessly roam around the hotel (i.e. they can use the device in their room and stay connected when they go down to the hotel's pool or restaurant). If we use a 255.255.255.0 subnet mask, we have 253 possible hosts to accommodate. When guests average 1 device per user, 100 devices on the network falls well within our 253 possible hosts. At an average of 2 devices per user, 200 devices on the network starts to come uncomfortably close to our 253 address limit. At an average of 3 devices per user (3-4 devices per guest is currently "common"), we've exceeded our address pool of 253 devices, meaning that 47 devices are not getting an address and getting on the network, leading to complaints, aggravated guests, aggravated staff, and future lost business. The same scenario in a 200 room hotel reaches that 253 host limit a lot more quickly. However, if we use a subnet that is a /22 (1021 usable addresses for guests) or /21 (2045 usable addresses for guests), we have increased the size of the local area network and thus the total address pool. Hopefully you found this explanation clear and straightforward. Any questions? Please post a comment.
