3com hub

transmission error. A modem is used to convert a computer's digital signal to a analog signal or vice versa for transmission over a telephone or Microwave Line. Modulation converts a digital signal to a analog signal. Demodulation converts a analog signal to a digital signal, which is generally connected to a computer through an RS-232 interface. 2. network physical layer interconnection devices 1. Repeater As signals have attenuation and noise in the network transmission media, the useful data

Seeing that the Internet cafes around him were so hot, Lao Zhang also made an investment. So we have the following story: Lao Zhang borrowed money to open an Internet cafe! I bought a new computer! The network composition is not smooth, silly! ...... Time is money! What should we do? Lao Zhang quickly found this "world-class man ". I did not live up to the title of "Prawn", and it was done in less than an hour. Maybe you will ask, where is the reason? How can this problem be solved? Don't be bus

bandwidth of the hub port, which determines that the transmission speed of the switch is much faster than that of the hub. (4) different transmission modes the hub can only transmit data in half duplex mode, because the hub is shared transport medium, in this way, the hub

connection. This sharing solution is not suitable for enterprises or families that need to filter employees or children online. The network connection is the same as that of the LAN. The two machines can be directly connected through cables (including twisted pair cables and cables, and parallel cables ). Generally, three or more machines use a hub or vswitch to form a star network (you can also use a dual Nic to connect devices without a collec

This article is to introduce two very representative distributed firewall system at present. At present, some well-known foreign network equipment developers in the distributed firewall technology more advanced, the product performance is also relatively high, using the "Software + Hardware" form. Host firewall for the integration of distributed firewall technology hardware products, and firewall server is a software form to adapt to more flexible and high intelligence requirements, such as

all 4 pairs of wires be used for signal transmission, while the other two standards require only 2 pairs of wires. The most common in Fast Ethernet is the 100BASE-TX standard, so when buying a twisted pair used in a 100M network, some network vendors or companies provide only 2 pairs of twisted pair, on the grounds that Fast Ethernet requires only 2 pairs of wires to transmit information. 7. When making the straight line, is not sure to follow the 568B standard to do.Answer: No. A pass-through

common HUB, that is, a HUB, lags behind a switched HUB (vswitch) in its working mode. Therefore, when funds are sufficient, the speed of using a switch is much faster. But it is better to use some of the miscellaneous vswitches, rather than buy a 3COM or D-LINK with more money. If the funds are insufficient, it is bes

"switch", it is the upgrading of the hub of the product, from the appearance, it and the hub is basically not much different, are the cuboid with multiple ports. The switch is according to the communication both ends transmission information need, uses the manual or the equipment automatic completion method to send transmits the information to meet the request the corresponding route the technical general

applicable to IP and IPX traffic, it also applies to IP address multiplexing and bridge traffic. Catalyst 2948G-L3 supports a high-performance architecture with 22 Gbps bandwidth. The Switched Optical Fiber supports all 48 10/100 ports and 2 gigabit uplink connections at a wire speed. The Catalyst 2948G-L3 can be installed in a 1.5RU chassis and can be equipped with an optional external redundant power supply. It supports 22 Gbit/s shared memory, completely non-blocking switching optical fiber,

successful network administrators. Essential Qualities for successful network management: switches and hubs) The English name of a vswitch is "Switch". It is an upgraded product of a hub. In terms of appearance, it is basically no different from a hub. It is a cube with multiple ports. A vswitch is a technology collectively referred to as a technology that sends the information to be transmitted manually o

software, scattered development of various applications, lack of unified planning, resulting in low-level repeated development, low level of information sharing, and unbalanced development. In general, a complete system cannot be formed. In this context, the Ministry of Railways proposed the idea of building a railway operation management information system (OIS). Its core is the transportation management information system (TMIS ). TMIS consists of the central database system, station segment

sequence, and traffic control. At present, some high-end switches also have some new functions, such as VLAN (Virtual LAN) support, link aggregation support, and even some also have routing and firewall functions.　　A vswitch is a network device that can encapsulate and forward data packets based on MAC address recognition. At present, the mainstream switch manufacturers to foreign CISCO (CISCO), 3COM, annett as the representative, the main domestic H

distributed to other computers. A common HUB, that is, a HUB, lags behind a switched HUB (vswitch) in its working mode. Therefore, when funds are sufficient, the speed of using a switch is much faster. But it is better to use some of the miscellaneous vswitches, rather than buy a 3COM or D-LINK with more money. If the

The English name of a vswitch is "Switch". It is an upgraded product of a hub. In terms of appearance, it is basically no different from a hub. It is a cube with multiple ports. A vswitch is a technology collectively referred to as a technology that sends the information to be transmitted manually or automatically by devices to a route that meets the requirements. The main functions of a vswitch include ph

distributed to other computers. A common HUB, that is, a HUB, lags behind a switched HUB (vswitch) in its working mode. Therefore, when funds are sufficient, the speed of using a switch is much faster. But it is better to use some of the miscellaneous vswitches, rather than buy a 3COM or D-LINK with more money. If the

junk communication packets to the entire switching network, the switch is misunderstood as a broadcast storm. In short, direct forwarding applies to network environments with good network link quality and fewer error packets. Storage and forwarding technology: Store-and-Forward) The storage and forwarding technology requires the switch to decide how to forward after receiving all data packets. In this way, the switch can check the integrity and correctness of data packets before forwarding. The

communication packets to the entire switching network, the switch is misunderstood as a broadcast storm. In short, direct forwarding applies to network environments with good network link quality and fewer error packets. Storage forwarding technology: (store-and-forward) The storage and forwarding technology requires the switch to decide how to forward after receiving all data packets. In this way, the switch can check the integrity and correctness of data packets before forwarding. The advanta

network, and all data is allocated to other computers. The general hub, the hub, because of its way of working behind switched hubs (switches), it is much faster to use the switch with sufficient funding. But some of the best of the kitchen switch is not used, rather than spend more money to buy a 3COM, D-link. If you don't have enough money, you can use a bette

line expensive, installation is also more difficult, coupled with the home LAN structure simple, less equipment, so there is no need to use shielded twisted pair. The choice of network cards is relatively simple, the current network card is basically 10/100mbps adaptive, if your machine does not integrate the network card, the choice of digital Shenzhou, Tatsu and other well-known manufacturers of products can be, D-link is also good. 3Com