Overview of FIFO and WFQ
First-in-first-out (FIFO) and weighted fair queuing (WFQ) are the two primary default queuing mechanisms that are implemented on Cisco routers. Despite a number of drawbacks, FIFO is the most-used queuing mechanism and it is supported in all versions of Cisco IOS. WFQ, which dynamically divides available bandwidth by a calculation based on the total number of flows and the weight of each given flow, was developed to resolve some of the problems resulting from the use of basic queuing methods, including FIFO, such as queue starvation, delay, and jitter.

The FIFO queuing mechanism
FIFO queuing has no classification because all packets belong to the same class. Packets are dropped when the output queue is full – this process is known as tail dropping. The scheduler services packets in the order in which they arrive. The software FIFO queue is basically an extension of the hardware FIFO queue. (more…)

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One of the primary purposes of a network is to increase productivity by linking computers and computer networks, so that people have easy access to information regardless of differences in time, place, or type of computer system.

Components of a network

Because companies have adopted networks as part of their business strategy, they typically subdivide and map corporate networks to the corporate business structure. In the figure, the network is defined based on the grouping of employees (users) into a main office and various remote access locations.

A main office is a site where everyone is connected via a LAN and where the bulk of corporate information is located. A main office can have hundreds or even thousands of people who depend on network access to do their jobs. It may have several LANs, or it may be a campus that contains several buildings. Because everyone needs access to central resources and information, it is common to see a high-speed backbone in a LAN as well as a data center with high-performance computers or servers and networked applications.

A variety of remote access locations connect to the main office or each other using WAN services as follows: (more…)

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Network applications are software programs that run between different computers connected together on a network.

Network applications

Network applications are software programs that run between different computers connected together on a network.

Some of the more common uses of network applications include using a web browser program to find content from the World Wide Web, or using an e-mail program to send e-mails over the Internet.

Network applications are selected based on the type of work that needs to be done. A complete set of application-layer programs is available to interface with the Internet. Each application program type is associated with its own application protocol. Some examples include: (more…)

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Do you have any idea how much a pieces of Original Cisco Console Cable? Does DIY Cisco Console Cable cheaper?

According to the vendor ,the Original Cisco Console Cable worth approximate RM100 above (60USD++). Usually Cisco console cable only come with each Cisco product you bought, but I found that ebay just sold at around 5USD to 10USD exclude shipping fees, while local website sold at RM60 above.

Should be those user who bough a lot Cisco switches and router, and they only use few to configure their Cisco device.

I was thinking does any Cisco’s Freak out there custom DIY their own Cisco Console Cable? I guess I am one of the “freak” who plan to do it.

Before I get start to DIY Cisco Console Cable, I require to know the arrangement of the cable. Arrangement on the RJ45 pin and another end at DB9 port.

Let study on the serial port numbering location 1st (DB9),  and RJ45 numbering location 1st. below are the port number for DB9 connector and RJ45 port number: (more…)

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Computer networking, like most industries, has its own jargon, which includes technical terms, abbreviations, and acronyms. Without a good grasp of the terminology, it will be difficult to understand the concepts and processes involved in networking. The following list of terms and their definitions is intended to be a quick reference that defines some of the most important words, phrases, and acronyms related to computer networking:

• A network interface card (NIC), pronounced “nick,” is also called the LAN adapter, or just the network interface. This card typically goes into an ISA, PCI, or PCMCIA (PC card) slot in a computer and connects to the network medium. It then connects to other computers through the network media.
• Media refers to the various physical environments through which transmission signals pass. Common network media include twisted-pair, coaxial, and fiber-optic cable, and even the earth’s atmosphere through which wireless transmission occurs.
• A protocol is a set of rules. In the case of a network protocol, it is a set of rules by which computers communicate. The term “protocol suite” describes a set of several protocols that perform different functions related to different aspects of the communication process.
• Cisco IOS software which runs on Cisco equipment and devices, is the industry-leading and most widely deployed network system software. It delivers intelligent network services for enabling the rapid deployment of Internet applications.

Cisco IOS software provides a wide range of functionality, from basic connectivity, security, and network management to technically advanced services. The functionality of Cisco IOS software is the result of a technological evolution. First-generation networking devices could only store and forward data packets. (more…)

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