SubnetPing is a small but useful tool to determine information about used IPv4-addresses in an IPv4 network.
Due to possible limitations of user rights within the operating system or system settings and network conditions in which you use SubnetPing, it is possible that the functionality is limited is some kind.
Discover the IPv4-Addresses from online hosts on the Subnet.
Detect IPv4-Addresses (IPv4) Scan an entire IPv4/24 (Class C) subnet by sending IMCP echo requests to all possible hosts in the selected subnet. SubnetPing uses the default network interface the operating system and local routing table offers for this task. It should be possible detect available hosts in remote subnets, behind routers, remote networks thru an VPN, or even public networks as long as the hosts respond to IMCP echo requests and the TTL is high enough so that the packet will no be dropped by any router in the path.
Discover the IPv6-Addresses from online hosts on the Local Link.
This is the same as Ipv4 detection but due to the gigantic address space of Ipv6 its not possible detect them using IMCP or to resolve the MAC address using ARP requests. Fortunately it is possible to detect Ipv6 local link addresses and MAC-Addresses using the Neighbor Discovery Protocol (NDP). This is an very early stage functionality and has some restrictions:
- Ping should work fine.
- Hops will always be “0” due to detection method restrictions.
- Packetloss should work fine.
- MAC-Addresses should work fine.
- Hostnames should work fine.
- Ports should work fine.
Discover the MAC-Addresses thru ARP requests from online hosts on the Subnet.
Determine the MAC-Addresses by sending ARP requests to all available hosts. This works only on the local subnet of the Computer your scanning from. It is not possible to resolve the MAC-Address of any device behind a router using ARP requests.
Resolve the Hostnames thru DNS requests from online hosts on the Subnet.
Determine the Hostnames by using the operating system's default DNS server of the default network interface that is selected thru the routing table for accessing hosts in subnet be be scanned. This works only on the local subnet of the Computer your scanning from, due to the lack of revers lookup DNS entries in an public DNS Server.
Ping hosts on the Subnet.
The Ping time is determined by sending an IMCP echo request to the target IPv4 and waiting for the IMCP echo reply. The Ping time is the locally measured time from sending the IMCP echo request to the target until the IMCP echo reply received. The IMCP echo reply has to be received within a give time-frame (timeout), or the Ping attempted will be considered as a timeout and the IMCP echo reply will be dropped.
Resolve Hops to hosts on the Subnet.
Determine Hops (number of routers in the path) There is no 100% accurate way to get this information. SubnetPing uses an approximation technique to guess the hop count based on some assumptions. This is because the router has do decrease the TTL by at least one, and most of routers do exactly that. The reply packets might have another base TTL than your request packet had. The base TTL has starts at 256,128,64 or 32. Therefore it should be correct if the packet has less than 32 hops in total and every router in the path decreased it by only one.
- received a response with TTL 32,64,128,256 we assume there was no hop.
- received a response with TTL 31,63,127,255 we assume there was 1 hop.
- received a response with TTL 30,62,126,255 we assume there was 2 hops. ...and so on...
Scan each online host on the Subnet for some 'default' Open Ports.
Check for Packetloss to hosts on the Subnet.
Packetloss is calculated based on the attempts to ping an host with an IMCP echo request and the number of received echo reply responses within a given time-frame (timeout).
Traceroute several (IPv4, or IPv6) Hosts Addresses at once and generate a visual representation of all the routes to the given targets.
Discover SNMP devices on the Subnet.
Determine the device description using SNMPv1 and SNMPv2 requests via UDP port 161. There are still some problems detecting SNMP devices. Some devices respond only to SNMPv1 community = “public“, OID = “18.104.22.168.22.214.171.124.0“ As others only respond to SNMPv2 community = “public“, OID = “126.96.36.199.188.8.131.52.0“ In some devices SNMP is just disabled by default and unfortunately there are still some devices that will not respond to SNMPv1 or SNMPv2 community = “public“ requests due to administration settings. These devices will only respond to authenticated SNMPv3 requests.
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downloading or using SubnetPing ("Application").
By downloading or using the Application, you are agreeing to be bound by the terms and conditions of this Agreement.
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If you do not agree to the terms of this Agreement, do not download or use the Application.
The software and the required documentation, if any, are provided as-is.
The Application is licensed, not sold, to you by SubnetPing for use strictly in accordance with the terms of this Agreement.
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41836 Hückelhoven - Ratheim
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41836 Hückelhoven - Ratheim