RS232 Port Monitor comes with a slew of powerful features, including advanced filtering and search options, built-in terminal, convenient data visualizers, the ability to record serial communication data to a file, and more. The software has a streamlined and user-friendly interface and doesn’t require any programming skills. After the data transmission process is over, TCP automatically terminates the connection between two separate endpoints. Summary TCP 3-way handshake or three-way handshake or TCP 3-way handshake is a process which is used in a TCP/IP network to make a connection between server and client. Syn use to initiate and establish a connection. Capsa Free is a network analyzer that allows you to monitor network traffic, troubleshoot network issues and analyze packets. Features include support for over 300 network protocols (including the ability to create and customize protocols), MSN and Yahoo Messenger filters, email monitor and auto-save, and customizable reports and dashboards. SmartSniff - Capture TCP/IP packets on your network adapter SocketSniff - Windows Sockets (WinSock) Sniffer See Also. NK2Edit - Edit, merge and fix the AutoComplete files (.NK2) of Microsoft Outlook. Description CurrPorts is network monitoring software that displays the list of all currently opened TCP/IP and UDP ports on your local computer. Axence nVision 12.0.1.30105. Our Rating: User Rating: Popularity: 6 Axence nVision is a network management suite that combines network monitoring and visualization, hardware and software inventory, intelligent user monitoring (and website blocking), data leak protection and remote desktop.
Port monitors consist of user-mode DLLs. They are responsible for providing a communications path between the user-mode print spooler and the kernel-mode port drivers that access I/O port hardware. A port monitor typically uses the CreateFile, WriteFile, ReadFile, and DeviceIOControl functions, described in the Microsoft Windows SDK documentation, to communicate with kernel-mode port drivers. Port monitors are also responsible for management and configuration of a server's printer ports, as described in Managing a Port.
An NT-based-operating system user's view of a 'printer' is really a print queue, to which one or more physical printer devices can be connected. A port is the physical connection between the print queue and a single printer device. Each port monitor supports one or more instances of one or more types of ports. For example Localmon.dll, the sample port monitor, can support all of a server's local COM and LPT ports. (The print folder assigns ports to port monitors by calling the Windows SDK documentation's AddPrinter function.)
For print queues representing multiple printer devices (through multiple ports), the spooler sends each print job to the first available port. If the port monitor indicates that a specified port is busy or has encountered an error, the spooler resubmits the job to the queue, specifying another port supported by the port monitor.
Besides Localmon.dll, Windows 2000 and later operating system versions provide several additional port monitors. The Windows 2000 Server Resource Kit describes each of these port monitors. (This resource may not be available in some languages and countries.)
Customized port monitors can be written to support additional types of I/O port hardware.
For Windows 2000 and later, each port monitor is divided into two DLLs:
Port Monitor UI DLL
A port monitor's user interface DLL contains user interface functionality and executes on print client systems.
This DLL must reside in the client system's System32 subdirectory.
Port Monitor Server DLL
A port monitor's server DLL contains port communications functionality and executes on print servers. It must not display a user interface.
The UI DLL communicates with the server DLL by calling the spooler's XcvData function.
A sample port monitor is included in the Windows Driver Kit (WDK).
1. Technical Field
The present invention relates to security in a network computer environment. More specifically, the present invention relates to security in computer networks which use several TCP/IP ports.
2. Description of Related Art
As applications become increasingly net-centric, myriad TCP/IP ports are tapped to provide various functions undreamed of only a few years ago. Numerous applications now communicate via obscure, but dedicated, TCP/IP ports and accordingly, provisions must be made within each system to allow connections upon these ports as warranted. If this increase in port nomenclature and usage were not enough to confound security, the boundaries between “secured” and “unsecured” are becoming more difficult to fathom as well, as the old model of a bastion firewall marking the border between a hostile outside and a benign corporate environment is increasingly outmoded.
This blurring of the lines can be demonstrated firstly by the incorporation of multiple web-servers, and even multiple domains, within the “secure” side of organizational firewalls. As outsiders are permitted electronic entry into an organization through designated TCP/IP ports, the old “outside-is-dangerous, inside-is-safe” model breaks down. Furthermore, organizations are increasingly subject to multiple levels of security even within their firewalls; examples of this are school districts, which need deterrents not only from the outside world, but also between the student-accessible computers and the administrative computers housing grades and student records.
It is clear that old security paradigms based upon a singular, well-controlled entry point into an organization now solve only part of the problem. It is also apparent that new security methods must be developed to safeguard systems as individual entities, given this new level of complexity inherent in system's models.
Because of the ambiguities between which subnetwork, machines and directory structures are safe and which are not, the solution should exist on the individual systems themselves. Secondly, because each unique system is going to be tasked with primary job responsibilities, it is of great importance that the systems not be loaded with any CPU-intensive processes in monitoring port usage upon its own system. Minimizing the impact of such a monitoring tool upon any jobs running on the targeted system is paramount. Security must not be accompanied by significant reduction in the performance of the host systems.
Currently, solutions exist only at the firewall, with the limitations described above, or at the host level, with heavy demands upon the resources of the target system. Therefore, a port monitoring method that can be implemented on the individual client computers in a network, but does not add an undue processing burden, would be desirable.
The present invention provides a method for monitoring incoming data from an external computer network. The invention comprises polling all active port connections in a data processing system at regular intervals and comparing these connections to a table of authorized ports and IP addresses. Any unauthorized connections are logged and a network administrator is notified. The present invention can be implemented on clients within a computer network.
The novel features believed characteristic of the invention are set forth in the appended claims. The invention itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying drawings, wherein:
With reference now to the figures, and in particular with reference to
Distributed data processing system
For purposes of this application, a network computer is any computer coupled to a network that receives a program or other application from another computer coupled to the network. In the depicted example, server
In the depicted example, distributed data processing system
Referring to
Peripheral component interconnect (PCI) bus bridge
Additional PCI bus bridges
Those of ordinary skill in the art will appreciate that the hardware depicted in
The data processing system depicted in
With reference now to
An operating system runs on processor
Those of ordinary skill in the art will appreciate that the hardware in
Referring now to
Most hacker methodologies achieve entry on arcane ports. In fact, hacking tools exist which scan the range of TCP ports, from outside the target system, to search for security weaknesses. Thus, portmon runs on the target client to monitor entry into obscure TCP/IP ports.
Portmon is initiated synchronously, that is, at regular intervals which are determined by the network administrator (step
Once portmon has been initiated, it looks to see that the necessary lookup table is installed on the system (step
If the lookup table is properly installed, portmon proceeds to examine all active ports (step
For a given port connection, portmon consults the lookup table and finds what range of addresses are allowed to make such connections (step
If a given connection is from an illicit port, or from a known-good port, but from an illicit address, this fact is noted in an output log (step
Steps
Prior art approaches to providing security at the client level require constant monitoring of the contents of incoming traffic, which requires substantial processing. The present invention simply relies upon a synchronous “snapshot” of the connection ports and foreign IP addresses which are compared with a predefined lookup table, requiring far less processing resources. The present invention also relieves the network administrator from having to rely solely upon a firewall to screen the network from the outside world. By monitoring security at the client level, without imposing heavy processing loads on the target system, the present invention increases data security with a minimum of operator intervention and a minimum in performance degradation.
It is important to note that while the present invention has been described in the context of a fully functioning data processing system, those of ordinary skill in the art will appreciate that the processes of the present invention are capable of being distributed in the form of a computer readable medium of instructions and a variety of forms and that the present invention applies equally regardless of the particular type of signal bearing media actually used to carry out the distribution. Examples of computer readable media include recordable-type media, such as a floppy disk, a hard disk drive, a RAM, CD-ROMs, DVD-ROMs, and transmission-type media, such as digital and analog communications links, wired or wireless communications links using transmission forms, such as, for example, radio frequency and light wave transmissions. The computer readable media may take the form of coded formats that are decoded for actual use in a particular data processing system.
The description of the present invention has been presented for purposes of illustration and description, and is not intended to be exhaustive or limited to the invention in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiment was chosen and described in order to best explain the principles of the invention, the practical application, and to enable others of ordinary skill in the art to understand the invention for various embodiments with various modifications as are suited to the particular use contemplated.