Comptia A+ 1001 5.7

Slow transfer speed causes:

-Congestion at a switch/router or some other network-wide problem. Might be caused by user, such as transferring large amount of data over the network -Could be a problem with the network adapter -Computer could be infected with malware -Network cabling could be affected by interference. Such as poor termination of cables is a common cause of this problem

If experiencing connecitivty issues

1. Perform basic ping test, if you can ping another local system then the proble m is not in the cabling. 2. If you can't ping anything, check the cable connecticity, verify that the patch cord is good. Swap the patch cord to the wall socket for a known good one. Check switch and patch panel next if that doesn't work. 3. Connect a different host to the network port, if it connects suspect a problem with network adapter, Use Device Manager to verify the adapter's link properties are set correctly. 4. Swap the nrtwork adapfter with a known good one and re-test. If this doesn't work, plug the computer into a different network port.

What is the loopback address?

127.0.0.1 it is a reserved IP address used for testing purposes

Low RF Signa/RSSI *Received signal strength indication

Connection speed will drop if RSSI is not at a minimum required level. If the RSSI is too low, the adapter will drop connection entirely and try to use a different network. Try moving to a location with better reception.

What does 169.254.x.y indicate?

Could not contact a DHCP server and is uting Automatic Private IP Addressing APIPA. Windows will display a yellow alrert icon and a notification that the adapter only has Limited Connectivity

Reduced transfer speed

It could be reduced if the network equipment is not all working to the highest avaiilable standard. -Check the configuration of the network adapter (via Device Manger) and the setting for the switch port (via the switch's management software)

Troubleshooting Wireless Signlal Issues such as intermittent connection

It is likely that there is interference from another radio source broadcasting at the same frequency. Try adjusting the channel that the device s use. -Also could be another electromagnetic source such as a motor or microwave oven. Construction material such as wire mesh, plasterboard, concreten and mirrors can block and degrade signals. Try angling/repositioning the dvice

Access Point compatibility mode turned off

It will not be able to communicate with devices that support older standards. Also, when an older device joins the network, the performance of the whole network can be affected. If possible, upgrade 802.11b devices rather than letting them join the WLAN

"Destination unreachable" unsuccessful ping

No routing information. If the host is on the smae network, check the local IP configuration. If it is not a config error, there may be a hardware/cabling problem.

WiFi Analyzer

Shows signal strength measured in dBm. For example, -35 dBm or better would represent the best possible signal at 100%. -90 dBm or worse would represent 1%. Setting the network to use a less congested channel can improve performance

A single PC on a network cannot connect to the Internet? Where would you start troubleshooting?

Test the PC's IP configuration, specially the default gateway or name resolution, or you could also check that the cable is good.

SSID not found

The user could be out of range or broadcast of the SSI name might be suppressed.

If experiencing intermittent issues with structured cabling:

You'll want to use cable testing tools to determine the cause. The solution may involve installing a new permanent link, but there could also be a termination or external interference problem

netstat

can be used to investiage open ports and connections on the local host. You can use this tool to verify whether file sharing or email ports are open on a server

ipconfig /flushdns

clear the dns resolver cacge

tracert

cmd utility used to trace the route a packet of information takes to get it its target. If host cannot be located, it will eventually time out but will return every router that was attempted.

ipconfig /all

displays detailed configuration, including DHCP and DN servers, Mac address, and netbios status

ipconfig /renew

forces a DHCP client to renew the lease it has for an ip address

"No reply (request timed out" unsuccessful ping

host is unavialable or cannot route a reply back to computer. Check physical cabling and infrastructure devices such as the switch. If the host is on a remote network, use "tracert" Note that ICMP traffic is oftern blocked by firewalls

What command would you use to refresh the IP configuration con a client workstation?

ipconfig /renew

ipconfig /release AdapterName

releases the ip address obtained from a DHCP server so that the network adapters will no longer have an IP address

Radio frequency

signal from radio-based devices weakens considerably as the distance between the devices increases. If you experience slow transfer speed or cannot establish a connection try moving the devices closer together. -Check that the security and authentication parameters are configured on both devices

What windows tool is used to test the end-to-end path between 2 IP hosts on different networks?

tracert