802.1Q is also known as IEEE 802.1Q or VLAN tagging. It defines a virtual local area network. It is a protocol that allows virtual LANs to communicate with one another using a 3-layered router. It was developed as a part of IEEE 802.
Why Was The 802.1Q Standard Developed?
Large networks use up a lot of bandwidth and are slow. It is desirable to break up these huge LANs into smaller, more manageable networks. To address this problem, the 802.1Q standard was developed as a part of IEEE 802. This
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192.168.2.1 is a private IP address commonly used by the SMC and Belkin router manufacturers for device setup and troubleshooting. SMC and Belkin specialize in manufacturing home networking equipment that competes with Netgear, D-Link, and Linksys brands in the marketplace. The Internet Assigned Numbers Authority (IANA) does not grant exclusive use of the IP address to these companies; however, as other network equipment manufacturers are free to use the IP address if required or desired. If ano
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A routing table is an electronic document that stores the routes to the various nodes in a computer network. The nodes may be any kind of electronic device connected to the network. The Routing Table is usually stored in a router or networked computer in the form of a database or file. When data needs to be sent from one node to another on the network, the routing table is referred to in order to find the best possible route for the transfer of information.
Hop-by-hop Routing is a common routin
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The following steps elaborate on how to use the Ping utility to perform progressively more distant tests on network connectivity.
Ping the Loopback Address - Type Ping 127.0.0.1
Successfully pinging the loopback address verifies that TCP/IP is both installed and configured correctly on the local client. If the loopback test fails, it means IP stack is not answering. If any TCP drivers get corrupted, the network adapter is not functioning properly, or any other service is interrupting IP , then
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traceroute is a command which is used to trace the route of a packet through a TCP/IP network.
traceroute is a Unix command. Under Microsoft Windows, the traceroute command has been renamed `tracert`. Unix `traceroute` and Microsoft Windows `tracert` are designed to accomplish the same task, but differ in the way they display output, in the way they send test packets, and in the number of command line options they provide.
Sample `tracert` output
This is the result of tracing the network ro
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MPLS stands for Multi Protocol Label Switching. The MPLS is often referred to as the layer in between the Data Link and Network layers because of where it operates. The MPLS serves as a method to forward packets of data easily by using labels.
What are the Data Link and Network layers?
In the seven-layer OSI model, a model used to explain how a computer operates and communicates within itself. The Data Link and Network Layers are parts of this model, and correspond to the second and third laye
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IP Address classes were the original organizational structure for IP addresses. The specific address class would determine the maximum potential size for a computer network. The address class would define which of the specific bits of the address would be used to identify the network and network identification, the bits to identify the host computer and host ID, and total number of host subnets permitted per network. Five total classes of IP addresses were defined, class A through E. Although th
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ICMP is the Internet Control Message Protocol.
ICMP is a complementary protocol to IP (Internet Protocol). Like IP, ICMP resides on the Network Layer of the OSI Model.
ICMP is designed for sending control and test messages across IP networks.
Unlike the Transport Layer protocols TCP (Transmission Control Protocol) and UDP (User Datagram Protocol) which operate on top of IP, ICMP exists alongside IP.
The ability to understand ICMP is a requirement for any IP-compatible network device. However
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VRRP stands for Virtual Router Redundancy Protocol. The VRRP is a commonly used method to avoid network outages during important data transfers.
Data transfer can be highly susceptible to failure when sent by a single router network. To combat this problem, VRRP creates a virtual connection between routers within the same network and ties them together. If the initial router used to send the data fails for any reason, another router automatically takes over the transfer.
Is the VRRP a physic
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The Unix/Linux `traceroute` command and the Microsoft Windows `tracert` commands both accomplish the task of tracing network paths, but they do it in slightly different ways.
Both of these tools for tracing network routes send out a packet wth TTL (Time To Live) set to 1 and report it's destnation. Then, they send out a packet with TTL=2 and report it's destination. They continue until the packets reach their final destination or the TTL limit is exceeded.
The difference is that Unix
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