Android app for tracking Android devices on GpsGate Server. You can install this app from the Google Play store. Getting Started With GpsGate Tracker for Android. IBM WebSphere Application Server provides periodic fixes for the base and Network Deployment editions of release V8.5. The following is a complete listing of fixes. This is a list of notable port numbers used by protocols of the transport layer of the Internet protocol suite for the establishment of host-to-host connectivity. Angry IP Scanner - Documentation. Introduction. Scanning of computer networks (searching for addresses with known properties) is a practice that is often used by both network administrators and crackers. Although it is widely accepted that activity of the latter is often illegal, most of the time they depend on exactly the same tools that can be used for perfectly legitimate network administration – just like a kitchen knife that can be used maliciously. But why do administrators need to scan their own networks? There are plenty of answers: to check status of computers and various network devices (are they up or down), find spare addresses in statically- addressed networks, monitor the usage of server- type or P2. P applications, make inventory of available hardware and software, check for recently discovered holes in order to patch them, and much more things that are even difficult to foresee. Angry IP Scanner is widely- used open- source and multi- platform network scanner. As a rule, almost all such programs are open- source, because they are developed with the collaboration of many people without having any commercial goals. Secure networks are possible only with the help of open- source systems and tools, possibly reviewed by thousands of independent experts and hackers alike. Certainly, there are other network scanners in existence (especially single- host port scanners), however, most of them are not cross- platform, are too simple and do not offer the same level of extensibility and user- friendliness as Angry IP Scanner. The program’s target audience are network administrators, consultants, developers, who all use the tool every day and therefore have advanced requirements for usability, configurability, and extensibility. However, Angry IP Scanner aims to be very friendly to novice users as well. Theory of network scanning. Networking. Computer networks, especially large ones, are very heterogeneous – they are composed of many interconnected devices into subnetworks using different topologies, which are in their own turn interconnected into larger networks, etc. The point here is that thanks to bridges between networks, all of them can use different physical (and data link) mediums for communication, with PPP over dial- up, IEEE 8. Ethernet), and 8. Wi- Fi) being the most popular. The famous OSI model defines seven layers of networking protocols. While the layers 3 and 4 are the most interesting to scanners – they are guaranteed to exist in any (IP- based) network regardless of physical mediums and provided higher level services, other layers can be interesting as well: local network scans can make use of the 1st and the 2nd layers in order to bypass higher level filtering. Higher level protocols are interesting because they are actually the ones users are most interested in, thus network scanners most often reach these layers too in order to detect the actual running services that make use of scanned network and transport endpoints (addresses and ports). The Internet Protocol. IP, in “IP address” and “IP scanner”, means nothing more complex than Internet Protocol. Nowadays, thanks to the Internet, TCP/IP is the most widely spread network protocol that over the years has replaced many other LAN and WAN protocols – it is now used in the majority of networks not even directly connected to the Internet. An IP address is the unique identifier of a network interface in the network. Most of the world still uses the older IPv. Earth’s population of over 6 billion and the increasing usage of computers and mobile devices. In order to fix the problem, IPv. However, different tricks were employed in order to prolong IPv. CIDR and NAT – it is too expensive to make such a big switch. CIDR stands for Classless Inter- Domain Routing, that gave us “network prefix” size notation (e. CIDR then came to help with the introduction of network masks and special prefix notation, meaning how many bits from left to right are the same in all addresses that are on the same network. This allowed for much more flexible address range assignments to networks with varying sizes, fixing the situation when most organizations were too large for class C (2. B ranges (6. 5,5. And there were only 1. A networks with 1. NAT stands for Network Address Translation and is an artful idea of making addresses in private subnets (1. Internet as if they had public addresses. NAT is usually implemented by routers by translating addresses of outgoing packets to router’s own address and then doing the opposite translation for incoming packets from router’s own address to the private address of the host that initiated the connection. Until now, there are only a few ISPs worldwide supporting IPv. IPv. 6 networks to IPv. Angry IP Scanner was designed with IPv. IPv. 4 only, as it is currently more useful. Transport layer. While only IP protocol is fine for sending of packets between hosts, there is a need to differentiate multiple senders and receivers on each host (sockets). This possibilities are provided by transport protocols UDP (User Datagram Protocol), TCP (Transmission Control Protocol), and their companion, ICMP (Internet Control Message Protocol). All these protocols are independent of whether IPv. IPv. 6 is used underneath. Both UDP and TCP define . The notion of . While majority of services rely on TCP, there are some that do not require the overhead of handshakes, automatic retransmissions, etc – they use UDP, e. DNS (Domain Name Service), real- time audio and video streaming, multiplayer games, etc. ICMP is for various control messages interchanged by hosts and other network devices, used for TCP, UDP, and general IP packet transmission. Scanning. The word scan is derived from the Latin word scandere, which means to climb and later came to mean “to scan a verse of poetry,” because one could beat the rhythm by lifting and putting down one’s foot. The Middle English verb scannen, derived from scandere, came into Middle English in this sense (first recorded in a text composed before 1. In the 1. 6th century this highly specialized sense having to do with the close analysis of verse developed other senses, such as “to criticize, examine minutely, interpret, perceive.” From these senses having to do with examination and perception, it was an easy step to the sense “to look at searchingly” (first recorded in 1. In modern language, it usually may mean: “to examine closely”, “to look over quickly and systematically”, “to analyze”. In electronics, it usually means: “to move a finely focused beam . All these definitions can also be applied to the meaning used in computer technology that we are going to discuss below. What does a network scanner able to do? There are usually two types of network scanners: port scanners and IP scanners. Port scanners usually scan TCP and sometimes UDP ports of a single host by sequentially probing each of them. This is similar to walking around a shopping mall and writing down the list of all the shops you see there along with their status (open or closed). Another type are IP scanners that scan many hosts and then gather additional information about those of them that are available (alive). According to the shopping mall analogy, that would be walking around the city looking for all shopping malls and then discovering all kinds of shops that exist in each of the malls. As Angry IP Scanner is an IP scanner, designed for scanning of multiple hosts, this will be the type of network scanner reviewed in the following text. As a rule, user provides a list of IP addresses to the scanner with the goal of sequentially probing all of them and gathering interesting information about each address as well as overall statistics. The gathered information may include the following: whether the host is up (alive, responding) or down (dead, not responding)average roundtrip time (of IP packets to the destination address and back) – the same value as shown by the ping program. TTL (time to live) field value from the IP packet header, which can be used to find out the rough distance to the destination address (in number of routers the packet has traveled)host and domain name (by using a DNS reverse lookup)versions of particular services running on the host (e. Apache 2. 0. 3. 2 (Linux 2. TCP and UDP port numbers. Other options are also possible, e. Angry IP Scanner has several different modules for generation of IP addresses called feeders. Additional feeders can be added with the help of plugins. Safety and Security. The question of safety is always asked about security tools, like network scanners. So, how safe it is to use such programs? Fortunately, the short response is that it is both legal and safe, however with some exceptions. Nevertheless, scanning itself remains perfectly legal, because in most cases it neither harms the scanned systems in any way nor provides any direct possibilities of breaking into them. Network scanning is even used by some popular network applications for automatic discovery of peers and similar functionality. Most countries’ laws forbid getting illegal access to data, destroying, spoiling, modifying it, or reducing its usefulness or value in some other way . As a rule, the scanning results just provide the publicly available and freely obtainable information, collected and grouped together. However, this legality may not apply in case some more advanced stealth scanning techniques are used against a network you do not have any affiliation with. As the topic of user’s personal safety is covered: scanning in most cases is legal, then how about the more general safety – the safety of all the people? As was already mentioned before, nothing can be one hundred percent safe. On the other hand, the best tools for maintaining the security are the same ones that are used by those who are needed to be defended from. Only that way it is possible to understand how do crackers think and how do they work.
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