The internet sharing in the data network was done in unplanned manner where two internet connections where assigned to individual users, that is one connection per user, and the other two connections where supplying the rest of the data network, each connection assigned to a specific location that is the sales department have one connection and the drawing section has one connection, Microsoft internet sharing connection facility that is freely available in Windows client operating systems is used to share internet connection to the other devices, in each section, by default this type of connection will assign the gateway with a 192.168.0.1/24 IP address and by enabling the clients to get the IP addresses dynamical, they will all be assigned with an IP address from this subnet, since the same setup is used at the other section, an IP conflict occurs when the uplink cable is connected permanently. Therefore the link is being used as a back up, with the cable only plugged in when the link on the other side has failed.
All the connections are either using shielded twisted Pair or unshielded Cat5e cable which a maximum speed of 100Mbps. Though in practise this speed may be lower due to effect by external factors affecting the line, like electromagnetic current that can be relayed by the heavy machinery in the workshop area, hence this can be one reason the network seem to be slow.
4.2.1.1 HARDWARE DEVICES
• ADSL routers : There are four Belkin ADSL modems with built in routers, the routing capabilities are simple designed for home based usage, offering minimum security features and network address translation, dynamic host control protocol (DHCP) services.
• Switches: All the switches are entry level unmanaged switches. These sw...
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...d switches, which are lacking the capabilities to support management protocols or port mirroring, an alternative method was used, to capture the traffic and utilisation data of the network. A hub was used at the main office closed to the switch connecting to the internet machine.
The internet sharing was disabled at one side, the back up uplink cable was plugged and all traffic to and from the external network and servers was forced to pass through the hub, figure 4.2 shows the utilisation of the network, though the figure only shows a small portion, but the trend of the utilisation indicates that the network is not fully utilised and bottlenecks that cause slowness may be caused by other factors such the internet speed or interferences on the cable signal.
The interference on the line could not be measured as the device for measuring the line was not available.
The Jaagz’ local area network will use category 5 cable and run IEEE 802.3 protocol. Using IEEE 802.3, the network speed will average about 10 Mbps. It will utilize a combination of a star and bus topology, which is the most common topology used in networks. The bus topology makes up the backbone of the network while the star topology branches out.
A Hub is a networking device that allows one to connect multiple PCs to a single network. Hubs may be based on Ethernet, Firewire, or USB connections. “A switch is a control unit that turns the flow of electricity on or off in a circuit. It may also be used to route information patterns in streaming electronic data sent over networks. “
The corporate headquarters network in San Jose (see attachment 1) has 2 WAN connections. The first one is a T1 wired connection protected by an unknown firewall. The second connection is a satellite link to China no security devices noted. The network inventory includes:
Meanwhile, these massive files quickly began monopolizing the services of the central location network switch. Since the network was physically redundant throughout, the network components tried to calculate new paths along which the data could flow; but eventually became confused. Therefore, the redundant components intended to operate in tandem became primary and began to duplicate each other’s functions, resulting in an endless loop until the network was totally disabled. On the afternoon of November 13, 2002, every software application that required network communication abruptly stopped
Meanwhile, the advent of early PC’s and the recognition of the value in networking devices together gave rise to Local Area Networks. These LAN’s were developed from a business customer perspective, which placed more emphasis on costs and ease of use over reliability. There were a number of different competing LAN technologies, two of the most common being Token Ring (IBM) and Ethernet (everyone else). The triumph of Ethernet in the marketplace, to the extent where it is included in every PC, game console and some refrigerators, provides a consistent and relatively inexpensive way to build internal networks with relative ease.
All computers are connected to a hub, switch or router. Require more cabling, but failure of one node does not break down the network.
Token ring LAN speeds of 4Mbps, 16Mbps, 100Mbps and 1Gbps have been standardized by the IEEE 802.5 working group.
In order to have a greater understanding of the terminology and descriptions offered in this paper, we must first understand what a network switch is. A brief definition of a network switch is a computer networking device that connects network segments. It uses the logic of a Network bridge, but allows a physical and logical star topology. It is often used to replace network hubs. A switch is also often referred to as an intelligent hub.
Switches, which are layer 2 devices, use decision based routing by storing NIC hardware addresses and port numbers on a table in the switch. By doing this, when data is received by the switch, it knows where the source was, and where the data needs to go. This allows for faster data transmission for all NICS that are connected, because it uses the swi...
It can also be noted that there is a significant amount of the broadcast packets like ARP, NBNS and UDP, as shown in figure 4.6 a partial segment of the Wireshark output and due to these packets the switches should experience a vast number of broadcasts, which in general degrades the entire network performance.
...fice location will have a VPN capable router connected to the T1 connection. Various workstations will also be connected to the LAN at each office.
Our first step to assist ET in his wonderful networking' adventures was to start by researching for general information on the internet about the different router brands that are on the market. We narrowed our choices to two router brands: D-Link and Linksys. Afterwards we went to Circuit City and Best Buy to talk to their representatives and ask them questions about the two router brands we focused on. The representatives of both stores seemed to agree that the best routers to use were Linksys routers. They directed us to two different models of Linksys routers: the WRT54GS, and the WRT54G. We focused our in-depth research on those two models. From our dismay, we've discovered that most of the Linksys routers offer 4-port Ethernet switch (they will allow us to connect the desktop with wires), transfer rates up to 54 Mbps and advance security. The GS model offers additional speed and higher security, but it requires extra hardware. We located two routers that would completely satisfy our needs based upon our budget (see Annex A for a more detailed comparaison).
In communication networks, research was performed on Fiber Optics Local Area Networks such as Fastnet, Expressnet, D-Net, U-Net and Token Ring as they are key networks for factory automation. This leads to interest in modelling and testing of High Speed Networks, which is paramount for the successful development of multimedia systems.
Berean¡¦s existing network infrastructure is wire line, and uses a T1. Remote users access the network through a dial-up modem pool. Berean¡¦s wire line network model severely limits the accessibility and effectiveness of the Berean network. For example, employees in Berean facilities are unable to access the network easily from meetings, the cafeteria, or anywhere other than their offices. In addition, the effectiveness of remote users is limited by the slow speed of present-day dial-up modem connections.
By 2004, the wireless subscriber base worldwide is expected to reach 1.4 billion users, and approximately 300 million users will be accessing the Internet from some form of wireless appliance. The race is on, and Nortel Networks have first-mover advantage.