‫Well, what do open, closed or filtered actually means?
‫Let's take a closer look at the results of unmap when A sends packets to a port and receives a positive
‫response.
‫The port is assigned the state of open, for example, since Gane receives a Sinak from the destination
‫system if the port is open.
‫If Unmap determines that a port is not available, it assigns it the closed state, this signifies it,
‫and MAP has received a result that clearly shows that the port is closed.
‫A sin scan receiving a receipt in response to a port query is an example of a closed port.
‫Filtered ports are the result of a packet filter or firewall when no response at all is received from
‫the remote device.
‫The port is considered to be filtered.
‫A response isn't received from the port and map of an retries communication to the port to ensure that
‫the packet wasn't simply dropped due to error or congestion.
‫Please note that this type of response is categorized differently.
‫If this is a different scan type, such as a UDP scan or a fin scan, the next result, open filter
‫is coming in a minute.
‫On the other hand, if the destination systems return, an unexpected response.
‫Again, the port is considered to be filtered.
‫If we get an ICMP unreachable response in a sense scan, the port is flagged as filtered.
‫Now, in some cases, the lack of a response may not necessarily mean that a port is filtered.
‫Lack of a response might mean that the port might also be open now in these situations, and map signifies
‫that the port is either filtered or open, for example, in a UDP connection.
‫In most cases, the destination system does not send a response when it receives a UDP packet.
‫So if the destination system does not respond and map categorizes it as open, filtered makes sense.
‫In this slide, you see some of the most known default ports.
‫So here's a question, if the Port 22 is open, is the service running there?
‫Absolutely.
‫And S.H., could there be another service?
‫Well, these are the default port numbers of the services.
‫You can run any service in any port.
‫You can run HTP on board 22, for example.
‫But for the ease of use, the default ports are used in general.
‫So if you're performing a test, you should probably look at the well-known ports first, but you should
‫never just scan the default ports.
‫There are different ways to scan ports within map.
‫Let's see how we can scan ports.
‫Let's prepare a second scan for him, Métis portable device, the IP address of my meds voidable is
‫one seven two one six eight nine nine two zero six.
‫If you do not use any one of the port scanning parameters, top 1000 ports are scanned, top ports are
‫the most used ports in general.
‫The first way of choosing the ports to scan is using parameter.
‫After entering the scanned type and target IP.
‫Enter the port numbers with parameter.
‫You can at reports one by one, separated by a comma, or you can give a range of ports by putting a
‫dash between the port numbers.
‫In this example, the ports, 20 to 80 and the ports between 100 and 200 are scanned.
‫If you perform both TCP scan and UDP scan in a single and map query.
‫You can choose both the EDP boards and the TCP boards using parameter.
‫Where they send maps, scan will use both since scan and UDP scan at the same time, we haven't seen
‫it yet, but the UDP scan is performed using s capital you parameter.
‫And as you know, the cities scan is a type of TCP scan.
‫After entering the target IP put Desh P.
‫One or TCP words put uppercase T with a colon just after the parameter P and the T seaports to scan.
‫Sam is giving port numbers directly with parameter, you can enter ports one by one, separated by a
‫comma, or you can give a range of ports by putting a dash between the port numbers.
‫To specify the UDP reports put you as another case, you with a colon and the ports with the same format.
‫For this example, let's scan the TCP ports to an 80 and the UDP ports 53 and the ports between 139
‫and 150.
‫So here are the results, TCP ports first and then UDP ports.
‫Now, the way to specify the ports is using top ports parameter, using this with the number of ports
‫that will be scanned, you can scan the top ports within this parameter.
‫So let's scan top 20 ports for this example.
‫So here are the top results of the most used 20 ports.
‫If you use uppercase F, which means fast scan top 100 ports or scan.
‫So let's perform an end map since scan with a parameter here.
‫And open another terminal screen and perform another and map scan using top ports 100 parameter.
‫As you see, we get the same result because these are the same queries.
‫If you'd like to scan all the parts of the system.
‫Well, you should scan all the ports of the systems and append test, you have to use the parameter
‫with the interval from one to 65, 535.
‫This is a range of possible port numbers.
‫Prepare the maps and scan Creary with the destination IP address now put P one dash six five five three
‫five.
‫And hit enter.
‫Here are all the open ports of medicine voidable.
‫By default and MAP does host Discovery and then performs a port scan against each host it determines
‫is online.
‫If you use P N in the N McCreery, you skip host Discovery and Port, Skåne, all target hosts.
‫Disabling host discovery with poison causes and map to attempt the requested scanning functions against
‫every target IP address specified.
‫So if Class C target address space, that means 24 is specified on the command line, all 255 IP addresses
‫are scanned.
‫Why would we want to do this?
‫As you know, if you were a privileged user and MAP sends four types of packets to discover hosts ICMP
‫Echo Request Send Packet to TCP 443 Port.
‫Backpacked packett to TCP Port and ICMP timestamp request.
‫If a system is configured not to answer to ICMP request and if the ports 80 and 443 are filtered, then
‫that map thinks that the host is down even if it's up.
‫If you find a system which is not found by pings, can always use porn for further port scans otherwise.
‫And MAP doesn't perform the ports scan because it assumes that the host is not up.
‫So if your network is not big or if you don't have enough time to scan, you should skip the ping scan
‫and run the port scans for every possible IP address.
‫Use a sports fan instead of ping scan, if you were scanning a server block, because those systems
‫are configured to be more secure than usual.
‫Then you can find more computers than the ping scans do.
‫You're halfway there.