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| Q1: Does ProG-2000L work in 64 bit / 66 Mhz PCI slots? | |||
| A:Yes,
ProG2000L is compliant with both 32 and 64 bits PCI slots. Before
you install ProG2000L, please make sure your computer meet the following
the hardware / software requirements: 1. Intel Pentium 90 or faster 2. 16MB of RAM (Minimum) 3. PCI local bus 2.1 compliant 4. O/S: Windows 95 or higher 5. 32 or 64bit PCI slot |
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| Q2: What's the pin assign of UTP cable? | |||
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A:According to the EIA/TIA 586B standard, the color sequence of Category 5 UTP is as following figure. The Straight-through cable is used to connect between switch and PC. The Crossover cable is used to connect two switches. If your switch provides uplink port, you can connect two switches through Straight-through cable by linking one side to uplink port. If your switch is equipped with Auto-MDI/MDI-X function, you do not have to bother from straight-through or cross-over cables.
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| Q3: What's the difference between MAC-based VLAN and 802.1Q VLAN? | |||
| A:There
are two major differences between MAC-based and 802.1Q VLAN. First
of All, MAC-based VLAN is configured with MAC address, but 802.1Q
VLAN uses assigned tag address to distinguish VLAN information. Secondly,
MAC-based VLAN is a traditional and proprietary-based VLAN, so interoperability
is a problem. On the other hand, 802.1Q VLAN is an industry standard-based
VLAN, which helps resolve any interoperability problems between different
vendors of LAN switches. |
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| Q4: How can you use a switch to protect your current network investment? | |||
| A:A
Switch can be installed up-stream from existing hubs, routers, and
servers. It isn't necessary to remove or replace any existing equipment.
In doing this, you will create dedicated bandwidth for each device
at each port: - No Network Card change is necessary for stations or servers. - No cable or software driver changes are necessary anywhere. |
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| Q5: What kind of security do switches provide or support? | |||
| A:There
are two ways to use a switch to improve network security: 5.1 VLAN: A network administrator can define several VLANs and block access to each VLAN to prevent users from accessing servers for which they don't have access permission. Therefore, each VLAN group is separated from one another. 5.2 Mac address filtering: A network administrator can define a DA (Destination Address). For example, all packets from Port A have only one destination to go, Port B. Port A may be Client , and Port B can be Server. So other ports have no access to Port A transfer data. Using MAC address filtering, only users that are connected to port A can access the server connected to port B, other packets from other ports, even those whose DA is for the server on port B, will be dropped. |
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| Q6: What is Flow Control? | |||
| A:
During times of heavy network activity, a switch's port buffers will
receive too much traffic and fill up faster than the switch can send
the information. In cases like this, the switch tells the transmitting
device to wait so the information in the buffer can be sent. This
intervention is called flow control.
The method of flow control depends on whether the ports are set to Full - or Half- duplex. A non-standard but popular scheme called Back Pressure was used in Half-duplex links. The IEEE 802.3 committee established a standard called 802.3x Flow Control was used in Full-duplex links. |
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| Q7: Why do I need a switch? | |||
| A:The major reason you need a switch is because you want to extend your network distance and share bandwidth with more than one user. Besides, users can share networked peripherals, such as scanners, printers, etc. Or if a group of gamers want to play on-line games together. A switch, generally speaking, provides improved performance, simultaneous conversation, and consistent response times, less or no collision to deploy better network performance. Management switches even provide various functions to satisfy administrators' needs to manage numerous computers. | |||
| Q8: What is polarity reversal? | |||
| A:A
UTP cable consists of 4 pairs of twisted-pair cable, in which one
pair of wiring is used to transmit data and another pair is used to
receive data. To resist the disturbance, each pair send both "positive"
and "negative" signals simultaneously, denoted as TX+ and
TX-, as depicted below: Cable 1 TX+ ---> RX+ 3 Cable 2 TX- ---> RX- 6 Cable 3 RX+ <--- TX+ 1 Cable 4 Cable 5 Cable 6 RX- <--- TX- 2 Cable 7 Cable 8 Note that TX+ (1) connects to RX+ (3) and TX- (2) connects to RX-(6). If the cable is connected as the following way: 2 TX- ---> RX+ 3 1 TX+ ---> RX- 6 . We say it is polarity reversal, because the signal received from the other side is reversed. |
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| Q9: Do CNet's Network cards support IRQ sharing? | |||
| A:Yes,
CNet's PCI cards support IRQ sharing. To share an interrupt number
for PCI devices, your equipment needs to meet the following requirement: 1. The motherboard and its BIOS must support shared interrupts. 2. Both PCI devices must be able to share an interrupt. If any of these requirements are not met then the Network Card or another PCI device will not work properly. |
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| Q10: What is Auto-negotiation? | |||
| A:Auto-negotiation
is a mechanism that takes control of the cable when a connection is
established to a network device. Auto-negotiation detects the various modes that exist in the device on the other end of the wire, and advertises it own abilities to automatically configure the highest performance mode of interoperation. Auto-negotiation automatically switches to the correct technology, such as 10BASE-T, 100BASE-TX, or a corresponding Full Duplex mode. Once the highest performance common mode is determined, Auto-negotiation passes control of the cable to the appropriate technology and becomes transparent until the connection is broken. Auto-negotiation leverages the proven link function of 10BASE-T to provide robust operation over Category 3, 4, or 5 Unshielded Twisted Pair (UTP.) |
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| Q11: What are the benefits of Auto-negotiation? | |||
| A:Auto-negotiation
has become a basic feature of network equipment, and it provides the
following benefits: 11.1 Automatic Connection The primary benefit of Auto-negotiation is the automatic connection of the highest performance technology available without any intervention from a user, manager, or management software. 11.2 Backwards Compatibility If Auto-negotiation exists at only one end of a twisted-pair link, it finds that the Link device does not support the Auto-negotiation mechanism. Instead of exchanging configuration information, it examines the receiving signal. If Auto-negotiation finds that the signal matches a technology that the device itself supports, the technology will be triggered immediately. This function, also known as Parallel Detection, gives Auto-negotiation the ability to be compatible with any device that does not support Auto-negotiation. Yet Auto-negotiation still support 10BASE-T, and 100BASE-TX, connection to any technology by Parallel Detection other than those listed above is not supported by Auto-negotiation. 11.3 Network Protection Auto-negotiation assures preservation of network integrity and minimization of network down time. In particular, Hubs are a primary beneficiary of this feature. If a hub has Auto-negotiation, it will refuse the connection and allow the rest of the networks to continue as usual. In fact, with Auto-negotiation in the hub, the network users are protected from any connection that the hub cannot recognize of accept. 11.4 Upgrade Path New nodes on the market will have 100Mbps functionality as well as traditional 10BASE-T. This means that there will be some latent performance available as these new nodes are added to an old 10BASE-T network. When the performance issue becomes critical, the latent ability can be tapped into by upgrading the hub. Auto-negotiation enables the upgrade to occur without reconfiguring each node and/or each port on the new hub. |
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