Tag: CDMA

The TCP congestion control mechanism Cisco 1941-SEC Cisco 1941-SEC is the only cause of congestion for data loss, due tothe characteristics of wireless channel, the wireless network environment of large amounts of data due to switching, channel fading, interference and discarded, in this case if the TCPcongestion control, will reduce the data transmission rate is not necessary, cause bandwidth utilization rate is not high, the system delay increases, throughput decreases. 1 random packet loss (Random Loss) The traditional TCP congestion control mechanism is designed for wired networks. Almost negligible caused by bit errors and link error data loss. But in a wireless network, data loss is caused by fading. The IS-95 service based on CDMA data, 1% ~ 2% is the random packet loss. The 2 burst loss (Burst Loss) Burst loss in a very short time, result in the loss of many consecutive data. It is caused by thesignal fading. Wireless LAN as an example, on a mobile host, all traffic it (inflow and outflow) is through which is connected with the base station route. When a mobile host from coverage of a base station is removed, it needs another base in the exercise of its information to register. After all communication is accomplished through the new base station. However, when the switch, a series of data through the primordium station submitted to the mobile host packets will be lost.Therefore, you can switch to lead to the occurrence of burst loss events. 3 packet reordering (Packet Reordering) When the receiving end receives the order and the sending end to send the order of the packets are not at the same time, to packet reordering. The same is the wireless LAN as an example, reorder packets associated with switching. When a mobile host from a base station is switched to another base station, sent to the mobile host or is sent from the mobile host packets through the base station route of new information. Because the data packet transmission will experience a different RTT on different paths, resulting in packet cannot order delivery at. Cisco 2901 Cisco 2901

DM500 is a satellite signal receiver which is produced by DreamMedia Inc. Using a DM500; you can enjoy TV programs around the world. Since DM500 is such good object, how can we share it with our friends just using a common CDMA wireless Ethernet card?

Before we operate on the sharing project, we should make the basic hardware requirement ready. You need a laptop, a CDMA wireless Ethernet card, a coaxial cable which has Registered Jack on both of its end, a projector and a DM500 of course. If you have got all the objects mentioned above, lets start to build the sharing system. You have to follow the steps in order to make your system stable and work efficiently.

1. Turn down all the equipments; link the DM500 to the satellite antenna. Then connect DM500 and projector. Connect laptop and DM500 using the coaxial cable. Attach the CDMA card to laptop. After the processes above, you can turn on the equipments. Remember, the turning on order of equipments must be first DM500, then projector, finally laptop.

2. Set the network parameter. You have to set up the CDMA Ethernet card first. Do not let the autorun software installed on the card begins to run. Firstly, have a right click on the My Network Place icon (If your operating system is Windows 95 or Windows 98, the icons name is Network Neighborhood), then left click on the last option. There is a wireless LAN network option, right click on it and turn to the advanced options under the characteristic option card. Turn down the Windows firewall, click on all the sharing options. There will be a warning window when the DM500 connects laptop, click on Yes. Do not turn on CDMA card right now.

3. Set up the Internet protocol (TCP/IP). Change the IP address to 192.168.1.1, modify the netmask to 255.255.255.0. Then gill in the form about network parameters on DM500. The first line should be filled in 192.168.1.2. The second line should be filled with 255.255.255.0. The third line should be 192.168.1.1 and the last line is 192.168.1.1. Remember to store the modification.

4. Turn on the CDMA card though My Network Space. Do not let the cards own software run, or you cannot succeed.

5. Wait a minute and you can see the lights of Ethernet card, laptops Ethernet card and CDMA card are on at the same time, now your job is done!

Congratulations! Now you can share the DM500 with any network equipment.