what is portscan?

Question

what on earth is a portscan - one was ran on my computer the other day, my antivirus/firewall picked it up and blocked it but i have no idea what on earth it is

Answer 1

A port scan is a series of messages sent by someone attempting to break into a computer to learn which computer network services, each associated with a "well-known" port number, the computer provides. Port scanning, a favorite approach of computer cracker, gives the assailant an idea where to probe for weaknesses. Essentially, a port scan consists of sending a message to each port, one at a time. The kind of response received indicates whether the port is used and can therefore be probed for weakness.
Types of port scans include:

vanilla - An attempt to connect to all ports (there are 65,536)
Strobe - An attempt to connect to only selected ports (typically, under 20)
Stealth scan - Several techniques for scanning that attempt to prevent the request for connection being logged
FTP Bounce Scan - Attempts that are directed through an File Transfer Protocol server to disguise the cracker's location
Fragmented Packets - Scans by sending packet fragments that can get through simple packet filters in a firewall
UDP - Scans for open User Datagram Protocol ports
Sweep - Scans the same port on a number of computers

Answer 2

Hackers use a portscan to find out what ports your PC has and therefore find weak spots to hack into your system. Good thing your antivirus/firewall picked it up.

Answer 3

open google
type in...firewall test ...u will see this
https://www.grc.com/x/ne.dll?bh0bkyd2
and
http://www.hackerwatch.org/probe/
check these 2 spots out
u can use these tools to scan pc..find out if your firewall is blocking what it is supposed to.....u can see what ports are open..
u can scan ports for malware
here is one more good site with info
auditmypc.com
pcflank.com....try there stealth test....or exploit test
if u can pass these....ur pc is very safe

Answer 4

it means, someone or something was scanning your computer for an open port to acess your system. this is how people break into another computr